From 238756ab6ed11c014e2fe9304214dfed0286dcfb Mon Sep 17 00:00:00 2001
From: Adrien Loison <adrilo@users.noreply.github.com>
Date: Tue, 30 May 2017 00:56:50 +0200
Subject: [PATCH] Move Style classes into Common folder (#432)

---
 README.md                                     |   6 +-
 src/Spout/Writer/CSV/Writer.php               |   2 +-
 .../Creator}/Style/BorderBuilder.php          |   8 +-
 .../Creator}/Style/StyleBuilder.php           |   7 +-
 .../{ => Common/Entity}/Style/Border.php      |  17 +-
 .../{ => Common/Entity}/Style/BorderPart.php  |   4 +-
 .../{ => Common/Entity}/Style/Color.php       |   4 +-
 .../{ => Common/Entity}/Style/Style.php       | 203 +++++++-----------
 .../Common/Helper/StyleHelperAbstract.php     |  37 ++--
 .../Common/Helper/StyleHelperInterface.php    |   8 +-
 .../Writer/Common/Manager/StyleManager.php    | 118 ++++++++++
 .../Manager/WorkbookManagerAbstract.php       |   2 +-
 .../Manager/WorkbookManagerInterface.php      |   2 +-
 .../Manager/WorksheetManagerInterface.php     |   2 +-
 .../Exception/Border/InvalidNameException.php |   2 +-
 .../Border/InvalidStyleException.php          |   2 +-
 .../Border/InvalidWidthException.php          |   2 +-
 .../Writer/ODS/Creator/InternalFactory.php    |  13 +-
 src/Spout/Writer/ODS/Helper/BorderHelper.php  |   4 +-
 src/Spout/Writer/ODS/Helper/StyleHelper.php   |  18 +-
 .../Writer/ODS/Manager/OptionsManager.php     |   2 +-
 .../Writer/ODS/Manager/WorksheetManager.php   |   2 +-
 src/Spout/Writer/WriterAbstract.php           |  36 ++--
 src/Spout/Writer/WriterFactory.php            |  12 +-
 src/Spout/Writer/WriterInterface.php          |   6 +-
 .../Writer/WriterMultiSheetsAbstract.php      |   8 +-
 .../Writer/XLSX/Creator/InternalFactory.php   |  13 +-
 src/Spout/Writer/XLSX/Helper/BorderHelper.php |   4 +-
 src/Spout/Writer/XLSX/Helper/StyleHelper.php  |  18 +-
 .../Writer/XLSX/Manager/OptionsManager.php    |   2 +-
 .../Writer/XLSX/Manager/WorksheetManager.php  |   4 +-
 .../{ => Common/Entity}/Style/BorderTest.php  |  18 +-
 .../{ => Common/Entity}/Style/ColorTest.php   |   4 +-
 .../Manager/StyleManagerTest.php}             |  53 +++--
 .../Writer/ODS/Helper/StyleHelperTest.php     |  26 +--
 .../Spout/Writer/ODS/WriterWithStyleTest.php  |  22 +-
 .../Writer/XLSX/Helper/StyleHelperTest.php    |  45 ++--
 .../Spout/Writer/XLSX/WriterWithStyleTest.php |  25 +--
 38 files changed, 463 insertions(+), 298 deletions(-)
 rename src/Spout/Writer/{ => Common/Creator}/Style/BorderBuilder.php (90%)
 rename src/Spout/Writer/{ => Common/Creator}/Style/StyleBuilder.php (93%)
 rename src/Spout/Writer/{ => Common/Entity}/Style/Border.php (80%)
 rename src/Spout/Writer/{ => Common/Entity}/Style/BorderPart.php (97%)
 rename src/Spout/Writer/{ => Common/Entity}/Style/Color.php (96%)
 rename src/Spout/Writer/{ => Common/Entity}/Style/Style.php (58%)
 create mode 100644 src/Spout/Writer/Common/Manager/StyleManager.php
 rename tests/Spout/Writer/{ => Common/Entity}/Style/BorderTest.php (84%)
 rename tests/Spout/Writer/{ => Common/Entity}/Style/ColorTest.php (95%)
 rename tests/Spout/Writer/{Style/StyleTest.php => Common/Manager/StyleManagerTest.php} (67%)

diff --git a/README.md b/README.md
index 531b985..9650cc4 100644
--- a/README.md
+++ b/README.md
@@ -137,7 +137,7 @@ It is possible to apply some formatting options to a row. Spout supports fonts,
 ```php
 use Box\Spout\Common\Type;
 use Box\Spout\Writer\WriterFactory;
-use Box\Spout\Writer\Style\StyleBuilder;
+use Box\Spout\Writer\Common\Creator\Style\StyleBuilder;
 use Box\Spout\Writer\Style\Color;
 
 $style = (new StyleBuilder())
@@ -163,9 +163,9 @@ Adding borders to a row requires a ```Border``` object.
 ```php
 use Box\Spout\Common\Type;
 use Box\Spout\Writer\Style\Border;
-use Box\Spout\Writer\Style\BorderBuilder;
+use Box\Spout\Writer\Common\Creator\Style\BorderBuilder;
 use Box\Spout\Writer\Style\Color;
-use Box\Spout\Writer\Style\StyleBuilder;
+use Box\Spout\Writer\Common\Creator\Style\StyleBuilder;
 use Box\Spout\Writer\WriterFactory;
 
 $border = (new BorderBuilder())
diff --git a/src/Spout/Writer/CSV/Writer.php b/src/Spout/Writer/CSV/Writer.php
index 9740fd9..8bf3c0f 100644
--- a/src/Spout/Writer/CSV/Writer.php
+++ b/src/Spout/Writer/CSV/Writer.php
@@ -81,7 +81,7 @@ class Writer extends WriterAbstract
      *
      * @param  array $dataRow Array containing data to be written.
      *          Example $dataRow = ['data1', 1234, null, '', 'data5'];
-     * @param \Box\Spout\Writer\Style\Style $style Ignored here since CSV does not support styling.
+     * @param \Box\Spout\Writer\Common\Entity\Style\Style $style Ignored here since CSV does not support styling.
      * @return void
      * @throws \Box\Spout\Common\Exception\IOException If unable to write data
      */
diff --git a/src/Spout/Writer/Style/BorderBuilder.php b/src/Spout/Writer/Common/Creator/Style/BorderBuilder.php
similarity index 90%
rename from src/Spout/Writer/Style/BorderBuilder.php
rename to src/Spout/Writer/Common/Creator/Style/BorderBuilder.php
index c0b8aea..81609e0 100644
--- a/src/Spout/Writer/Style/BorderBuilder.php
+++ b/src/Spout/Writer/Common/Creator/Style/BorderBuilder.php
@@ -1,9 +1,15 @@
 <?php
 
-namespace Box\Spout\Writer\Style;
+namespace Box\Spout\Writer\Common\Creator\Style;
+
+use Box\Spout\Writer\Common\Entity\Style\Border;
+use Box\Spout\Writer\Common\Entity\Style\BorderPart;
+use Box\Spout\Writer\Common\Entity\Style\Color;
 
 /**
  * Class BorderBuilder
+ *
+ * @package \Box\Spout\Writer\Common\Creator\Style
  */
 class BorderBuilder
 {
diff --git a/src/Spout/Writer/Style/StyleBuilder.php b/src/Spout/Writer/Common/Creator/Style/StyleBuilder.php
similarity index 93%
rename from src/Spout/Writer/Style/StyleBuilder.php
rename to src/Spout/Writer/Common/Creator/Style/StyleBuilder.php
index 2676cbe..34e40d7 100644
--- a/src/Spout/Writer/Style/StyleBuilder.php
+++ b/src/Spout/Writer/Common/Creator/Style/StyleBuilder.php
@@ -1,12 +1,15 @@
 <?php
 
-namespace Box\Spout\Writer\Style;
+namespace Box\Spout\Writer\Common\Creator\Style;
+
+use Box\Spout\Writer\Common\Entity\Style\Border;
+use Box\Spout\Writer\Common\Entity\Style\Style;
 
 /**
  * Class StyleBuilder
  * Builder to create new styles
  *
- * @package Box\Spout\Writer\Style
+ * @package Box\Spout\Writer\Common\Creator\Style
  */
 class StyleBuilder
 {
diff --git a/src/Spout/Writer/Style/Border.php b/src/Spout/Writer/Common/Entity/Style/Border.php
similarity index 80%
rename from src/Spout/Writer/Style/Border.php
rename to src/Spout/Writer/Common/Entity/Style/Border.php
index 75f6a49..7046897 100644
--- a/src/Spout/Writer/Style/Border.php
+++ b/src/Spout/Writer/Common/Entity/Style/Border.php
@@ -1,9 +1,11 @@
 <?php
 
-namespace Box\Spout\Writer\Style;
+namespace Box\Spout\Writer\Common\Entity\Style;
 
 /**
  * Class Border
+ *
+ * @package \Box\Spout\Writer\Common\Entity\Style
  */
 class Border
 {
@@ -22,10 +24,8 @@ class Border
     const WIDTH_MEDIUM = 'medium';
     const WIDTH_THICK = 'thick';
 
-    /**
-     * @var array A list of BorderPart objects for this border.
-     */
-    protected $parts = [];
+    /** @var array A list of BorderPart objects for this border. */
+    private $parts = [];
 
     /**
      * @param array|void $borderParts
@@ -36,7 +36,7 @@ class Border
     }
 
     /**
-     * @param $name The name of the border part
+     * @param string $name The name of the border part
      * @return null|BorderPart
      */
     public function getPart($name)
@@ -45,7 +45,7 @@ class Border
     }
 
     /**
-     * @param $name The name of the border part
+     * @param string $name The name of the border part
      * @return bool
      */
     public function hasPart($name)
@@ -64,6 +64,7 @@ class Border
     /**
      * Set BorderParts
      * @param array $parts
+     * @return void
      */
     public function setParts($parts)
     {
@@ -75,7 +76,7 @@ class Border
 
     /**
      * @param BorderPart $borderPart
-     * @return self
+     * @return Border
      */
     public function addPart(BorderPart $borderPart)
     {
diff --git a/src/Spout/Writer/Style/BorderPart.php b/src/Spout/Writer/Common/Entity/Style/BorderPart.php
similarity index 97%
rename from src/Spout/Writer/Style/BorderPart.php
rename to src/Spout/Writer/Common/Entity/Style/BorderPart.php
index 9ade797..66a08c1 100644
--- a/src/Spout/Writer/Style/BorderPart.php
+++ b/src/Spout/Writer/Common/Entity/Style/BorderPart.php
@@ -1,6 +1,6 @@
 <?php
 
-namespace Box\Spout\Writer\Style;
+namespace Box\Spout\Writer\Common\Entity\Style;
 
 use Box\Spout\Writer\Exception\Border\InvalidNameException;
 use Box\Spout\Writer\Exception\Border\InvalidStyleException;
@@ -8,6 +8,8 @@ use Box\Spout\Writer\Exception\Border\InvalidWidthException;
 
 /**
  * Class BorderPart
+ *
+ * @package \Box\Spout\Writer\Common\Entity\Style
  */
 class BorderPart
 {
diff --git a/src/Spout/Writer/Style/Color.php b/src/Spout/Writer/Common/Entity/Style/Color.php
similarity index 96%
rename from src/Spout/Writer/Style/Color.php
rename to src/Spout/Writer/Common/Entity/Style/Color.php
index 3c86eb7..356f606 100644
--- a/src/Spout/Writer/Style/Color.php
+++ b/src/Spout/Writer/Common/Entity/Style/Color.php
@@ -1,6 +1,6 @@
 <?php
 
-namespace Box\Spout\Writer\Style;
+namespace Box\Spout\Writer\Common\Entity\Style;
 
 use Box\Spout\Writer\Exception\InvalidColorException;
 
@@ -8,7 +8,7 @@ use Box\Spout\Writer\Exception\InvalidColorException;
  * Class Color
  * This class provides constants and functions to work with colors
  *
- * @package Box\Spout\Writer\Style
+ * @package Box\Spout\Writer\Common\Entity\Style
  */
 class Color
 {
diff --git a/src/Spout/Writer/Style/Style.php b/src/Spout/Writer/Common/Entity/Style/Style.php
similarity index 58%
rename from src/Spout/Writer/Style/Style.php
rename to src/Spout/Writer/Common/Entity/Style/Style.php
index a1f7626..16268b1 100644
--- a/src/Spout/Writer/Style/Style.php
+++ b/src/Spout/Writer/Common/Entity/Style/Style.php
@@ -1,12 +1,12 @@
 <?php
 
-namespace Box\Spout\Writer\Style;
+namespace Box\Spout\Writer\Common\Entity\Style;
 
 /**
  * Class Style
  * Represents a style to be applied to a cell
  *
- * @package Box\Spout\Writer\Style
+ * @package Box\Spout\Writer\Common\Entity\Style
  */
 class Style
 {
@@ -16,62 +16,62 @@ class Style
     const DEFAULT_FONT_NAME = 'Arial';
 
     /** @var int|null Style ID */
-    protected $id = null;
+    private $id = null;
 
     /** @var bool Whether the font should be bold */
-    protected $fontBold = false;
+    private $fontBold = false;
     /** @var bool Whether the bold property was set */
-    protected $hasSetFontBold = false;
+    private $hasSetFontBold = false;
 
     /** @var bool Whether the font should be italic */
-    protected $fontItalic = false;
+    private $fontItalic = false;
     /** @var bool Whether the italic property was set */
-    protected $hasSetFontItalic = false;
+    private $hasSetFontItalic = false;
 
     /** @var bool Whether the font should be underlined */
-    protected $fontUnderline = false;
+    private $fontUnderline = false;
     /** @var bool Whether the underline property was set */
-    protected $hasSetFontUnderline = false;
+    private $hasSetFontUnderline = false;
 
     /** @var bool Whether the font should be struck through */
-    protected $fontStrikethrough = false;
+    private $fontStrikethrough = false;
     /** @var bool Whether the strikethrough property was set */
-    protected $hasSetFontStrikethrough = false;
+    private $hasSetFontStrikethrough = false;
 
     /** @var int Font size */
-    protected $fontSize = self::DEFAULT_FONT_SIZE;
+    private $fontSize = self::DEFAULT_FONT_SIZE;
     /** @var bool Whether the font size property was set */
-    protected $hasSetFontSize = false;
+    private $hasSetFontSize = false;
 
     /** @var string Font color */
-    protected $fontColor = self::DEFAULT_FONT_COLOR;
+    private $fontColor = self::DEFAULT_FONT_COLOR;
     /** @var bool Whether the font color property was set */
-    protected $hasSetFontColor = false;
+    private $hasSetFontColor = false;
 
     /** @var string Font name */
-    protected $fontName = self::DEFAULT_FONT_NAME;
+    private $fontName = self::DEFAULT_FONT_NAME;
     /** @var bool Whether the font name property was set */
-    protected $hasSetFontName = false;
+    private $hasSetFontName = false;
 
     /** @var bool Whether specific font properties should be applied */
-    protected $shouldApplyFont = false;
+    private $shouldApplyFont = false;
 
     /** @var bool Whether the text should wrap in the cell (useful for long or multi-lines text) */
-    protected $shouldWrapText = false;
+    private $shouldWrapText = false;
     /** @var bool Whether the wrap text property was set */
-    protected $hasSetWrapText = false;
+    private $hasSetWrapText = false;
 
     /** @var Border */
-    protected $border = null;
+    private $border = null;
 
     /** @var bool Whether border properties should be applied */
-    protected $shouldApplyBorder = false;
+    private $shouldApplyBorder = false;
 
     /** @var string Background color */
-    protected $backgroundColor = null;
+    private $backgroundColor = null;
 
     /** @var bool */
-    protected $hasSetBackgroundColor = false;
+    private $hasSetBackgroundColor = false;
 
 
     /**
@@ -138,6 +138,14 @@ class Style
         return $this;
     }
 
+    /**
+     * @return bool
+     */
+    public function hasSetFontBold()
+    {
+        return $this->hasSetFontBold;
+    }
+
     /**
      * @return bool
      */
@@ -157,6 +165,14 @@ class Style
         return $this;
     }
 
+    /**
+     * @return bool
+     */
+    public function hasSetFontItalic()
+    {
+        return $this->hasSetFontItalic;
+    }
+
     /**
      * @return bool
      */
@@ -176,6 +192,14 @@ class Style
         return $this;
     }
 
+    /**
+     * @return bool
+     */
+    public function hasSetFontUnderline()
+    {
+        return $this->hasSetFontUnderline;
+    }
+
     /**
      * @return bool
      */
@@ -195,6 +219,14 @@ class Style
         return $this;
     }
 
+    /**
+     * @return bool
+     */
+    public function hasSetFontStrikethrough()
+    {
+        return $this->hasSetFontStrikethrough;
+    }
+
     /**
      * @return int
      */
@@ -215,6 +247,14 @@ class Style
         return $this;
     }
 
+    /**
+     * @return bool
+     */
+    public function hasSetFontSize()
+    {
+        return $this->hasSetFontSize;
+    }
+
     /**
      * @return string
      */
@@ -237,6 +277,14 @@ class Style
         return $this;
     }
 
+    /**
+     * @return bool
+     */
+    public function hasSetFontColor()
+    {
+        return $this->hasSetFontColor;
+    }
+
     /**
      * @return string
      */
@@ -257,6 +305,14 @@ class Style
         return $this;
     }
 
+    /**
+     * @return bool
+     */
+    public function hasSetFontName()
+    {
+        return $this->hasSetFontName;
+    }
+
     /**
      * @return bool
      */
@@ -320,103 +376,4 @@ class Style
     {
         return $this->hasSetBackgroundColor;
     }
-
-    /**
-     * Serializes the style for future comparison with other styles.
-     * The ID is excluded from the comparison, as we only care about
-     * actual style properties.
-     *
-     * @return string The serialized style
-     */
-    public function serialize()
-    {
-        // In order to be able to properly compare style, set static ID value
-        $currentId = $this->id;
-        $this->setId(0);
-
-        $serializedStyle = serialize($this);
-
-        $this->setId($currentId);
-
-        return $serializedStyle;
-    }
-
-    /**
-     * Merges the current style with the given style, using the given style as a base. This means that:
-     *   - if current style and base style both have property A set, use current style property's value
-     *   - if current style has property A set but base style does not, use current style property's value
-     *   - if base style has property A set but current style does not, use base style property's value
-     *
-     * @NOTE: This function returns a new style.
-     *
-     * @param Style $baseStyle
-     * @return Style New style corresponding to the merge of the 2 styles
-     */
-    public function mergeWith($baseStyle)
-    {
-        $mergedStyle = clone $this;
-
-        $this->mergeFontStyles($mergedStyle, $baseStyle);
-        $this->mergeOtherFontProperties($mergedStyle, $baseStyle);
-        $this->mergeCellProperties($mergedStyle, $baseStyle);
-
-        return $mergedStyle;
-    }
-
-    /**
-     * @param Style $styleToUpdate (passed as reference)
-     * @param Style $baseStyle
-     * @return void
-     */
-    private function mergeFontStyles($styleToUpdate, $baseStyle)
-    {
-        if (!$this->hasSetFontBold && $baseStyle->isFontBold()) {
-            $styleToUpdate->setFontBold();
-        }
-        if (!$this->hasSetFontItalic && $baseStyle->isFontItalic()) {
-            $styleToUpdate->setFontItalic();
-        }
-        if (!$this->hasSetFontUnderline && $baseStyle->isFontUnderline()) {
-            $styleToUpdate->setFontUnderline();
-        }
-        if (!$this->hasSetFontStrikethrough && $baseStyle->isFontStrikethrough()) {
-            $styleToUpdate->setFontStrikethrough();
-        }
-    }
-
-    /**
-     * @param Style $styleToUpdate Style to update (passed as reference)
-     * @param Style $baseStyle
-     * @return void
-     */
-    private function mergeOtherFontProperties($styleToUpdate, $baseStyle)
-    {
-        if (!$this->hasSetFontSize && $baseStyle->getFontSize() !== self::DEFAULT_FONT_SIZE) {
-            $styleToUpdate->setFontSize($baseStyle->getFontSize());
-        }
-        if (!$this->hasSetFontColor && $baseStyle->getFontColor() !== self::DEFAULT_FONT_COLOR) {
-            $styleToUpdate->setFontColor($baseStyle->getFontColor());
-        }
-        if (!$this->hasSetFontName && $baseStyle->getFontName() !== self::DEFAULT_FONT_NAME) {
-            $styleToUpdate->setFontName($baseStyle->getFontName());
-        }
-    }
-
-    /**
-     * @param Style $styleToUpdate Style to update (passed as reference)
-     * @param Style $baseStyle
-     * @return void
-     */
-    private function mergeCellProperties($styleToUpdate, $baseStyle)
-    {
-        if (!$this->hasSetWrapText && $baseStyle->shouldWrapText()) {
-            $styleToUpdate->setShouldWrapText();
-        }
-        if (!$this->getBorder() && $baseStyle->shouldApplyBorder()) {
-            $styleToUpdate->setBorder($baseStyle->getBorder());
-        }
-        if (!$this->hasSetBackgroundColor && $baseStyle->shouldApplyBackgroundColor()) {
-            $styleToUpdate->setBackgroundColor($baseStyle->getBackgroundColor());
-        }
-    }
 }
diff --git a/src/Spout/Writer/Common/Helper/StyleHelperAbstract.php b/src/Spout/Writer/Common/Helper/StyleHelperAbstract.php
index 269b560..c6c9216 100644
--- a/src/Spout/Writer/Common/Helper/StyleHelperAbstract.php
+++ b/src/Spout/Writer/Common/Helper/StyleHelperAbstract.php
@@ -2,6 +2,9 @@
 
 namespace Box\Spout\Writer\Common\Helper;
 
+use Box\Spout\Writer\Common\Entity\Style\Style;
+use Box\Spout\Writer\Common\Manager\StyleManager;
+
 /**
  * Class StyleHelperAbstract
  * This class provides helper functions to manage styles
@@ -10,6 +13,9 @@ namespace Box\Spout\Writer\Common\Helper;
  */
 abstract class StyleHelperAbstract implements StyleHelperInterface
 {
+    /** @var StyleManager Style manager */
+    private $styleManager;
+
     /** @var array [SERIALIZED_STYLE] => [STYLE_ID] mapping table, keeping track of the registered styles */
     protected $serializedStyleToStyleIdMappingTable = [];
 
@@ -17,10 +23,13 @@ abstract class StyleHelperAbstract implements StyleHelperInterface
     protected $styleIdToStyleMappingTable = [];
 
     /**
-     * @param \Box\Spout\Writer\Style\Style $defaultStyle
+     * @param Style $defaultStyle
+     * @param StyleManager $styleManager
      */
-    public function __construct($defaultStyle)
+    public function __construct(Style $defaultStyle, StyleManager $styleManager)
     {
+        $this->styleManager = $styleManager;
+
         // This ensures that the default style is the first one to be registered
         $this->registerStyle($defaultStyle);
     }
@@ -29,12 +38,12 @@ abstract class StyleHelperAbstract implements StyleHelperInterface
      * Registers the given style as a used style.
      * Duplicate styles won't be registered more than once.
      *
-     * @param \Box\Spout\Writer\Style\Style $style The style to be registered
-     * @return \Box\Spout\Writer\Style\Style The registered style, updated with an internal ID.
+     * @param Style $style The style to be registered
+     * @return Style The registered style, updated with an internal ID.
      */
     public function registerStyle($style)
     {
-        $serializedStyle = $style->serialize();
+        $serializedStyle = $this->styleManager->serialize($style);
 
         if (!$this->hasStyleAlreadyBeenRegistered($style)) {
             $nextStyleId = count($this->serializedStyleToStyleIdMappingTable);
@@ -50,12 +59,12 @@ abstract class StyleHelperAbstract implements StyleHelperInterface
     /**
      * Returns whether the given style has already been registered.
      *
-     * @param \Box\Spout\Writer\Style\Style $style
+     * @param Style $style
      * @return bool
      */
     protected function hasStyleAlreadyBeenRegistered($style)
     {
-        $serializedStyle = $style->serialize();
+        $serializedStyle = $this->styleManager->serialize($style);
 
         // Using isset here because it is way faster than array_key_exists...
         return isset($this->serializedStyleToStyleIdMappingTable[$serializedStyle]);
@@ -65,7 +74,7 @@ abstract class StyleHelperAbstract implements StyleHelperInterface
      * Returns the registered style associated to the given serialization.
      *
      * @param string $serializedStyle The serialized style from which the actual style should be fetched from
-     * @return \Box\Spout\Writer\Style\Style
+     * @return Style
      */
     protected function getStyleFromSerializedStyle($serializedStyle)
     {
@@ -74,7 +83,7 @@ abstract class StyleHelperAbstract implements StyleHelperInterface
     }
 
     /**
-     * @return \Box\Spout\Writer\Style\Style[] List of registered styles
+     * @return Style[] List of registered styles
      */
     protected function getRegisteredStyles()
     {
@@ -84,7 +93,7 @@ abstract class StyleHelperAbstract implements StyleHelperInterface
     /**
      * Returns the default style
      *
-     * @return \Box\Spout\Writer\Style\Style Default style
+     * @return Style Default style
      */
     protected function getDefaultStyle()
     {
@@ -96,9 +105,9 @@ abstract class StyleHelperAbstract implements StyleHelperInterface
      * Apply additional styles if the given row needs it.
      * Typically, set "wrap text" if a cell contains a new line.
      *
-     * @param \Box\Spout\Writer\Style\Style $style The original style
+     * @param Style $style The original style
      * @param array $dataRow The row the style will be applied to
-     * @return \Box\Spout\Writer\Style\Style The updated style
+     * @return Style The updated style
      */
     public function applyExtraStylesIfNeeded($style, $dataRow)
     {
@@ -115,9 +124,9 @@ abstract class StyleHelperAbstract implements StyleHelperInterface
      *        A workaround would be to encode "\n" as "_x000D_" but it does not work
      *        on the Windows version of Excel...
      *
-     * @param \Box\Spout\Writer\Style\Style $style The original style
+     * @param Style $style The original style
      * @param array $dataRow The row the style will be applied to
-     * @return \Box\Spout\Writer\Style\Style The eventually updated style
+     * @return Style The eventually updated style
      */
     protected function applyWrapTextIfCellContainsNewLine($style, $dataRow)
     {
diff --git a/src/Spout/Writer/Common/Helper/StyleHelperInterface.php b/src/Spout/Writer/Common/Helper/StyleHelperInterface.php
index a73d1cb..9066178 100644
--- a/src/Spout/Writer/Common/Helper/StyleHelperInterface.php
+++ b/src/Spout/Writer/Common/Helper/StyleHelperInterface.php
@@ -13,8 +13,8 @@ interface StyleHelperInterface
      * Registers the given style as a used style.
      * Duplicate styles won't be registered more than once.
      *
-     * @param \Box\Spout\Writer\Style\Style $style The style to be registered
-     * @return \Box\Spout\Writer\Style\Style The registered style, updated with an internal ID.
+     * @param \Box\Spout\Writer\Common\Entity\Style\Style $style The style to be registered
+     * @return \Box\Spout\Writer\Common\Entity\Style\Style The registered style, updated with an internal ID.
      */
     public function registerStyle($style);
 
@@ -22,9 +22,9 @@ interface StyleHelperInterface
      * Apply additional styles if the given row needs it.
      * Typically, set "wrap text" if a cell contains a new line.
      *
-     * @param \Box\Spout\Writer\Style\Style $style The original style
+     * @param \Box\Spout\Writer\Common\Entity\Style\Style $style The original style
      * @param array $dataRow The row the style will be applied to
-     * @return \Box\Spout\Writer\Style\Style The updated style
+     * @return \Box\Spout\Writer\Common\Entity\Style\Style The updated style
      */
     public function applyExtraStylesIfNeeded($style, $dataRow);
 }
diff --git a/src/Spout/Writer/Common/Manager/StyleManager.php b/src/Spout/Writer/Common/Manager/StyleManager.php
new file mode 100644
index 0000000..25a0d1d
--- /dev/null
+++ b/src/Spout/Writer/Common/Manager/StyleManager.php
@@ -0,0 +1,118 @@
+<?php
+
+namespace Box\Spout\Writer\Common\Manager;
+
+use Box\Spout\Writer\Common\Entity\Style\Style;
+
+/**
+ * Class StyleManager
+ * Manages styles to be applied to a cell
+ *
+ * @package Box\Spout\Writer\Common\Manager\Style
+ */
+class StyleManager
+{
+    /**
+     * Serializes the style for future comparison with other styles.
+     * The ID is excluded from the comparison, as we only care about
+     * actual style properties.
+     *
+     * @param Style $style
+     * @return string The serialized style
+     */
+    public function serialize(Style $style)
+    {
+        // In order to be able to properly compare style, set static ID value
+        $currentId = $style->getId();
+        $style->setId(0);
+
+        $serializedStyle = serialize($style);
+
+        $style->setId($currentId);
+
+        return $serializedStyle;
+    }
+
+    /**
+     * Merges the current style with the given style, using the given style as a base. This means that:
+     *   - if current style and base style both have property A set, use current style property's value
+     *   - if current style has property A set but base style does not, use current style property's value
+     *   - if base style has property A set but current style does not, use base style property's value
+     *
+     * @NOTE: This function returns a new style.
+     *
+     * @param Style $style
+     * @param Style $baseStyle
+     * @return Style New style corresponding to the merge of the 2 styles
+     */
+    public function merge(Style $style, Style $baseStyle)
+    {
+        $mergedStyle = clone $style;
+
+        $this->mergeFontStyles($mergedStyle, $style, $baseStyle);
+        $this->mergeOtherFontProperties($mergedStyle, $style, $baseStyle);
+        $this->mergeCellProperties($mergedStyle, $style, $baseStyle);
+
+        return $mergedStyle;
+    }
+
+    /**
+     * @param Style $styleToUpdate (passed as reference)
+     * @param Style $style
+     * @param Style $baseStyle
+     * @return void
+     */
+    private function mergeFontStyles(Style $styleToUpdate, Style $style, Style $baseStyle)
+    {
+        if (!$style->hasSetFontBold() && $baseStyle->isFontBold()) {
+            $styleToUpdate->setFontBold();
+        }
+        if (!$style->hasSetFontItalic() && $baseStyle->isFontItalic()) {
+            $styleToUpdate->setFontItalic();
+        }
+        if (!$style->hasSetFontUnderline() && $baseStyle->isFontUnderline()) {
+            $styleToUpdate->setFontUnderline();
+        }
+        if (!$style->hasSetFontStrikethrough() && $baseStyle->isFontStrikethrough()) {
+            $styleToUpdate->setFontStrikethrough();
+        }
+    }
+
+    /**
+     * @param Style $styleToUpdate Style to update (passed as reference)
+     * @param Style $style
+     * @param Style $baseStyle
+     * @return void
+     */
+    private function mergeOtherFontProperties(Style $styleToUpdate, Style $style, Style $baseStyle)
+    {
+        if (!$style->hasSetFontSize() && $baseStyle->getFontSize() !== Style::DEFAULT_FONT_SIZE) {
+            $styleToUpdate->setFontSize($baseStyle->getFontSize());
+        }
+        if (!$style->hasSetFontColor() && $baseStyle->getFontColor() !== Style::DEFAULT_FONT_COLOR) {
+            $styleToUpdate->setFontColor($baseStyle->getFontColor());
+        }
+        if (!$style->hasSetFontName() && $baseStyle->getFontName() !== Style::DEFAULT_FONT_NAME) {
+            $styleToUpdate->setFontName($baseStyle->getFontName());
+        }
+    }
+
+    /**
+     * @param Style $styleToUpdate Style to update (passed as reference)
+     * @param Style $style
+     * @param Style $baseStyle
+     * @return void
+     */
+    private function mergeCellProperties(Style $styleToUpdate, Style $style, Style $baseStyle)
+    {
+        if (!$style->hasSetWrapText() && $baseStyle->shouldWrapText()) {
+            $styleToUpdate->setShouldWrapText();
+        }
+        if (!$style->getBorder() && $baseStyle->shouldApplyBorder()) {
+            $styleToUpdate->setBorder($baseStyle->getBorder());
+        }
+        if (!$style->shouldApplyBackgroundColor() && $baseStyle->shouldApplyBackgroundColor()) {
+            $styleToUpdate->setBackgroundColor($baseStyle->getBackgroundColor());
+        }
+    }
+}
diff --git a/src/Spout/Writer/Common/Manager/WorkbookManagerAbstract.php b/src/Spout/Writer/Common/Manager/WorkbookManagerAbstract.php
index 050f673..96d4ff9 100644
--- a/src/Spout/Writer/Common/Manager/WorkbookManagerAbstract.php
+++ b/src/Spout/Writer/Common/Manager/WorkbookManagerAbstract.php
@@ -12,7 +12,7 @@ use Box\Spout\Writer\Common\Entity\Worksheet;
 use Box\Spout\Writer\Exception\SheetNotFoundException;
 use Box\Spout\Writer\Exception\WriterException;
 use Box\Spout\Writer\Common\Creator\EntityFactory;
-use Box\Spout\Writer\Style\Style;
+use Box\Spout\Writer\Common\Entity\Style\Style;
 
 /**
  * Class WorkbookManagerAbstract
diff --git a/src/Spout/Writer/Common/Manager/WorkbookManagerInterface.php b/src/Spout/Writer/Common/Manager/WorkbookManagerInterface.php
index e410004..fcd8854 100644
--- a/src/Spout/Writer/Common/Manager/WorkbookManagerInterface.php
+++ b/src/Spout/Writer/Common/Manager/WorkbookManagerInterface.php
@@ -8,7 +8,7 @@ use Box\Spout\Writer\Common\Entity\Workbook;
 use Box\Spout\Writer\Common\Entity\Worksheet;
 use Box\Spout\Writer\Exception\SheetNotFoundException;
 use Box\Spout\Writer\Exception\WriterException;
-use Box\Spout\Writer\Style\Style;
+use Box\Spout\Writer\Common\Entity\Style\Style;
 
 /**
  * Interface WorkbookManagerInterface
diff --git a/src/Spout/Writer/Common/Manager/WorksheetManagerInterface.php b/src/Spout/Writer/Common/Manager/WorksheetManagerInterface.php
index 4904c84..8f41559 100644
--- a/src/Spout/Writer/Common/Manager/WorksheetManagerInterface.php
+++ b/src/Spout/Writer/Common/Manager/WorksheetManagerInterface.php
@@ -3,7 +3,7 @@
 namespace Box\Spout\Writer\Common\Manager;
 
 use Box\Spout\Writer\Common\Entity\Worksheet;
-use Box\Spout\Writer\Style\Style;
+use Box\Spout\Writer\Common\Entity\Style\Style;
 
 /**
  * Interface WorksheetManagerInterface
diff --git a/src/Spout/Writer/Exception/Border/InvalidNameException.php b/src/Spout/Writer/Exception/Border/InvalidNameException.php
index 13ac06c..329323a 100644
--- a/src/Spout/Writer/Exception/Border/InvalidNameException.php
+++ b/src/Spout/Writer/Exception/Border/InvalidNameException.php
@@ -3,7 +3,7 @@
 namespace Box\Spout\Writer\Exception\Border;
 
 use Box\Spout\Writer\Exception\WriterException;
-use Box\Spout\Writer\Style\BorderPart;
+use Box\Spout\Writer\Common\Entity\Style\BorderPart;
 
 class InvalidNameException extends WriterException
 {
diff --git a/src/Spout/Writer/Exception/Border/InvalidStyleException.php b/src/Spout/Writer/Exception/Border/InvalidStyleException.php
index c684339..f3261f0 100644
--- a/src/Spout/Writer/Exception/Border/InvalidStyleException.php
+++ b/src/Spout/Writer/Exception/Border/InvalidStyleException.php
@@ -3,7 +3,7 @@
 namespace Box\Spout\Writer\Exception\Border;
 
 use Box\Spout\Writer\Exception\WriterException;
-use Box\Spout\Writer\Style\BorderPart;
+use Box\Spout\Writer\Common\Entity\Style\BorderPart;
 
 class InvalidStyleException extends WriterException
 {
diff --git a/src/Spout/Writer/Exception/Border/InvalidWidthException.php b/src/Spout/Writer/Exception/Border/InvalidWidthException.php
index 32f092b..0f24faf 100644
--- a/src/Spout/Writer/Exception/Border/InvalidWidthException.php
+++ b/src/Spout/Writer/Exception/Border/InvalidWidthException.php
@@ -3,7 +3,7 @@
 namespace Box\Spout\Writer\Exception\Border;
 
 use Box\Spout\Writer\Exception\WriterException;
-use Box\Spout\Writer\Style\BorderPart;
+use Box\Spout\Writer\Common\Entity\Style\BorderPart;
 
 class InvalidWidthException extends WriterException
 {
diff --git a/src/Spout/Writer/ODS/Creator/InternalFactory.php b/src/Spout/Writer/ODS/Creator/InternalFactory.php
index a2adb05..8677639 100644
--- a/src/Spout/Writer/ODS/Creator/InternalFactory.php
+++ b/src/Spout/Writer/ODS/Creator/InternalFactory.php
@@ -7,6 +7,7 @@ use Box\Spout\Writer\Common\Manager\OptionsManagerInterface;
 use Box\Spout\Writer\Common\Entity\Options;
 use Box\Spout\Writer\Common\Creator\EntityFactory;
 use Box\Spout\Writer\Common\Creator\InternalFactoryInterface;
+use Box\Spout\Writer\Common\Manager\StyleManager;
 use Box\Spout\Writer\ODS\Helper\FileSystemHelper;
 use Box\Spout\Writer\ODS\Helper\StyleHelper;
 use Box\Spout\Writer\ODS\Manager\WorkbookManager;
@@ -80,7 +81,17 @@ class InternalFactory implements InternalFactoryInterface
     private function createStyleHelper(OptionsManagerInterface $optionsManager)
     {
         $defaultRowStyle = $optionsManager->getOption(Options::DEFAULT_ROW_STYLE);
-        return new StyleHelper($defaultRowStyle);
+        $styleManager = $this->createStyleManager();
+
+        return new StyleHelper($defaultRowStyle, $styleManager);
+    }
+
+    /**
+     * @return StyleManager
+     */
+    private function createStyleManager()
+    {
+        return new StyleManager();
     }
 
     /**
diff --git a/src/Spout/Writer/ODS/Helper/BorderHelper.php b/src/Spout/Writer/ODS/Helper/BorderHelper.php
index f3c3fed..a619ffd 100644
--- a/src/Spout/Writer/ODS/Helper/BorderHelper.php
+++ b/src/Spout/Writer/ODS/Helper/BorderHelper.php
@@ -2,8 +2,8 @@
 
 namespace Box\Spout\Writer\ODS\Helper;
 
-use Box\Spout\Writer\Style\BorderPart;
-use Box\Spout\Writer\Style\Border;
+use Box\Spout\Writer\Common\Entity\Style\BorderPart;
+use Box\Spout\Writer\Common\Entity\Style\Border;
 
 /**
  * Class BorderHelper
diff --git a/src/Spout/Writer/ODS/Helper/StyleHelper.php b/src/Spout/Writer/ODS/Helper/StyleHelper.php
index e8a4110..29e15b4 100644
--- a/src/Spout/Writer/ODS/Helper/StyleHelper.php
+++ b/src/Spout/Writer/ODS/Helper/StyleHelper.php
@@ -3,7 +3,7 @@
 namespace Box\Spout\Writer\ODS\Helper;
 
 use Box\Spout\Writer\Common\Helper\StyleHelperAbstract;
-use Box\Spout\Writer\Style\BorderPart;
+use Box\Spout\Writer\Common\Entity\Style\BorderPart;
 
 /**
  * Class StyleHelper
@@ -20,8 +20,8 @@ class StyleHelper extends StyleHelperAbstract
      * Registers the given style as a used style.
      * Duplicate styles won't be registered more than once.
      *
-     * @param \Box\Spout\Writer\Style\Style $style The style to be registered
-     * @return \Box\Spout\Writer\Style\Style The registered style, updated with an internal ID.
+     * @param \Box\Spout\Writer\Common\Entity\Style\Style $style The style to be registered
+     * @return \Box\Spout\Writer\Common\Entity\Style\Style The registered style, updated with an internal ID.
      */
     public function registerStyle($style)
     {
@@ -209,7 +209,7 @@ EOD;
     /**
      * Returns the contents of the "<style:style>" section, inside "<office:automatic-styles>" section
      *
-     * @param \Box\Spout\Writer\Style\Style $style
+     * @param \Box\Spout\Writer\Common\Entity\Style\Style $style
      * @return string
      */
     protected function getStyleSectionContent($style)
@@ -229,7 +229,7 @@ EOD;
     /**
      * Returns the contents of the "<style:text-properties>" section, inside "<style:style>" section
      *
-     * @param \Box\Spout\Writer\Style\Style $style
+     * @param \Box\Spout\Writer\Common\Entity\Style\Style $style
      * @return string
      */
     private function getTextPropertiesSectionContent($style)
@@ -246,7 +246,7 @@ EOD;
     /**
      * Returns the contents of the "<style:text-properties>" section, inside "<style:style>" section
      *
-     * @param \Box\Spout\Writer\Style\Style $style
+     * @param \Box\Spout\Writer\Common\Entity\Style\Style $style
      * @return string
      */
     private function getFontSectionContent($style)
@@ -291,7 +291,7 @@ EOD;
     /**
      * Returns the contents of the "<style:table-cell-properties>" section, inside "<style:style>" section
      *
-     * @param \Box\Spout\Writer\Style\Style $style
+     * @param \Box\Spout\Writer\Common\Entity\Style\Style $style
      * @return string
      */
     private function getTableCellPropertiesSectionContent($style)
@@ -326,7 +326,7 @@ EOD;
     /**
      * Returns the contents of the borders definition for the "<style:table-cell-properties>" section
      *
-     * @param \Box\Spout\Writer\Style\Style $style
+     * @param \Box\Spout\Writer\Common\Entity\Style\Style $style
      * @return string
      */
     private function getBorderXMLContent($style)
@@ -343,7 +343,7 @@ EOD;
     /**
      * Returns the contents of the background color definition for the "<style:table-cell-properties>" section
      *
-     * @param \Box\Spout\Writer\Style\Style $style
+     * @param \Box\Spout\Writer\Common\Entity\Style\Style $style
      * @return string
      */
     private function getBackgroundColorXMLContent($style)
diff --git a/src/Spout/Writer/ODS/Manager/OptionsManager.php b/src/Spout/Writer/ODS/Manager/OptionsManager.php
index 20d42d7..4a83428 100644
--- a/src/Spout/Writer/ODS/Manager/OptionsManager.php
+++ b/src/Spout/Writer/ODS/Manager/OptionsManager.php
@@ -4,7 +4,7 @@ namespace Box\Spout\Writer\ODS\Manager;
 
 use Box\Spout\Writer\Common\Entity\Options;
 use Box\Spout\Writer\Common\Manager\OptionsManagerAbstract;
-use Box\Spout\Writer\Style\StyleBuilder;
+use Box\Spout\Writer\Common\Creator\Style\StyleBuilder;
 
 /**
  * Class OptionsManager
diff --git a/src/Spout/Writer/ODS/Manager/WorksheetManager.php b/src/Spout/Writer/ODS/Manager/WorksheetManager.php
index 016336b..cb8894a 100644
--- a/src/Spout/Writer/ODS/Manager/WorksheetManager.php
+++ b/src/Spout/Writer/ODS/Manager/WorksheetManager.php
@@ -9,7 +9,7 @@ use Box\Spout\Writer\Common\Entity\Cell;
 use Box\Spout\Writer\Common\Entity\Worksheet;
 use Box\Spout\Writer\Common\Manager\WorksheetManagerInterface;
 use Box\Spout\Writer\ODS\Helper\StyleHelper;
-use Box\Spout\Writer\Style\Style;
+use Box\Spout\Writer\Common\Entity\Style\Style;
 
 /**
  * Class WorksheetManager
diff --git a/src/Spout/Writer/WriterAbstract.php b/src/Spout/Writer/WriterAbstract.php
index 1425406..06abb3e 100644
--- a/src/Spout/Writer/WriterAbstract.php
+++ b/src/Spout/Writer/WriterAbstract.php
@@ -6,8 +6,11 @@ use Box\Spout\Common\Exception\InvalidArgumentException;
 use Box\Spout\Common\Exception\IOException;
 use Box\Spout\Common\Exception\SpoutException;
 use Box\Spout\Common\Helper\FileSystemHelper;
-use Box\Spout\Writer\Common\Manager\OptionsManagerInterface;
+use Box\Spout\Common\Helper\GlobalFunctionsHelper;
 use Box\Spout\Writer\Common\Entity\Options;
+use Box\Spout\Writer\Common\Entity\Style\Style;
+use Box\Spout\Writer\Common\Manager\OptionsManagerInterface;
+use Box\Spout\Writer\Common\Manager\StyleManager;
 use Box\Spout\Writer\Exception\WriterAlreadyOpenedException;
 use Box\Spout\Writer\Exception\WriterNotOpenedException;
 
@@ -28,13 +31,16 @@ abstract class WriterAbstract implements WriterInterface
     /** @var bool Indicates whether the writer has been opened or not */
     protected $isWriterOpened = false;
 
-    /** @var \Box\Spout\Common\Helper\GlobalFunctionsHelper Helper to work with global functions */
+    /** @var GlobalFunctionsHelper Helper to work with global functions */
     protected $globalFunctionsHelper;
 
-    /** @var \Box\Spout\Writer\Common\Manager\OptionsManagerInterface Writer options manager */
+    /** @var OptionsManagerInterface Writer options manager */
     protected $optionsManager;
 
-    /** @var Style\Style Style to be applied to the next written row(s) */
+    /** @var StyleManager Style manager */
+    protected $styleManager;
+
+    /** @var Style Style to be applied to the next written row(s) */
     protected $rowStyle;
 
     /** @var string Content-Type value for the header - to be defined by child class */
@@ -53,7 +59,7 @@ abstract class WriterAbstract implements WriterInterface
      *
      * @param  array $dataRow Array containing data to be streamed.
      *          Example $dataRow = ['data1', 1234, null, '', 'data5'];
-     * @param Style\Style $style Style to be applied to the written row
+     * @param Style $style Style to be applied to the written row
      * @return void
      */
     abstract protected function addRowToWriter(array $dataRow, $style);
@@ -66,11 +72,13 @@ abstract class WriterAbstract implements WriterInterface
     abstract protected function closeWriter();
 
     /**
-     * @param \Box\Spout\Writer\Common\Manager\OptionsManagerInterface $optionsManager
+     * @param OptionsManagerInterface $optionsManager
+     * @param StyleManager $styleManager
      */
-    public function __construct(OptionsManagerInterface $optionsManager)
+    public function __construct(OptionsManagerInterface $optionsManager, StyleManager $styleManager)
     {
         $this->optionsManager = $optionsManager;
+        $this->styleManager = $styleManager;
         $this->resetRowStyleToDefault();
     }
 
@@ -79,7 +87,7 @@ abstract class WriterAbstract implements WriterInterface
      * Overriding the default style instead of using "addRowWithStyle" improves performance by 20%.
      * @see https://github.com/box/spout/issues/272
      *
-     * @param Style\Style $defaultStyle
+     * @param Style $defaultStyle
      * @return WriterAbstract
      */
     public function setDefaultRowStyle($defaultStyle)
@@ -233,7 +241,7 @@ abstract class WriterAbstract implements WriterInterface
      *
      * @api
      * @param array $dataRow Array of array containing data to be streamed.
-     * @param Style\Style $style Style to be applied to the row.
+     * @param Style $style Style to be applied to the row.
      * @return WriterAbstract
      * @throws \Box\Spout\Common\Exception\InvalidArgumentException If the input param is not valid
      * @throws \Box\Spout\Writer\Exception\WriterNotOpenedException If this function is called before opening the writer
@@ -241,7 +249,7 @@ abstract class WriterAbstract implements WriterInterface
      */
     public function addRowWithStyle(array $dataRow, $style)
     {
-        if (!$style instanceof Style\Style) {
+        if (!$style instanceof Style) {
             throw new InvalidArgumentException('The "$style" argument must be a Style instance and cannot be NULL.');
         }
 
@@ -289,7 +297,7 @@ abstract class WriterAbstract implements WriterInterface
      *
      * @api
      * @param array $dataRows Array of array containing data to be streamed.
-     * @param Style\Style $style Style to be applied to the rows.
+     * @param Style $style Style to be applied to the rows.
      * @return WriterAbstract
      * @throws \Box\Spout\Common\Exception\InvalidArgumentException If the input param is not valid
      * @throws \Box\Spout\Writer\Exception\WriterNotOpenedException If this function is called before opening the writer
@@ -297,7 +305,7 @@ abstract class WriterAbstract implements WriterInterface
      */
     public function addRowsWithStyle(array $dataRows, $style)
     {
-        if (!$style instanceof Style\Style) {
+        if (!$style instanceof Style) {
             throw new InvalidArgumentException('The "$style" argument must be a Style instance and cannot be NULL.');
         }
 
@@ -312,14 +320,14 @@ abstract class WriterAbstract implements WriterInterface
      * Sets the style to be applied to the next written rows
      * until it is changed or reset.
      *
-     * @param Style\Style $style
+     * @param Style $style
      * @return void
      */
     private function setRowStyle($style)
     {
         // Merge given style with the default one to inherit custom properties
         $defaultRowStyle = $this->optionsManager->getOption(Options::DEFAULT_ROW_STYLE);
-        $this->rowStyle = $style->mergeWith($defaultRowStyle);
+        $this->rowStyle = $this->styleManager->merge($style, $defaultRowStyle);
     }
 
     /**
diff --git a/src/Spout/Writer/WriterFactory.php b/src/Spout/Writer/WriterFactory.php
index 7b2e9b5..3105665 100644
--- a/src/Spout/Writer/WriterFactory.php
+++ b/src/Spout/Writer/WriterFactory.php
@@ -6,7 +6,8 @@ use Box\Spout\Common\Exception\UnsupportedTypeException;
 use Box\Spout\Common\Helper\GlobalFunctionsHelper;
 use Box\Spout\Common\Type;
 use Box\Spout\Writer\Common\Creator\EntityFactory;
-use Box\Spout\Writer\Style\StyleBuilder;
+use Box\Spout\Writer\Common\Creator\Style\StyleBuilder;
+use Box\Spout\Writer\Common\Manager\StyleManager;
 
 /**
  * Class WriterFactory
@@ -54,8 +55,9 @@ class WriterFactory
     private static function getCSVWriter()
     {
         $optionsManager = new CSV\Manager\OptionsManager();
+        $styleManager = new StyleManager();
 
-        return new CSV\Writer($optionsManager);
+        return new CSV\Writer($optionsManager, $styleManager);
     }
 
     /**
@@ -65,9 +67,10 @@ class WriterFactory
     {
         $styleBuilder = new StyleBuilder();
         $optionsManager = new XLSX\Manager\OptionsManager($styleBuilder);
+        $styleManager = new StyleManager();
         $generalFactory = new XLSX\Creator\InternalFactory(new EntityFactory());
 
-        return new XLSX\Writer($optionsManager, $generalFactory);
+        return new XLSX\Writer($optionsManager, $styleManager, $generalFactory);
     }
 
     /**
@@ -77,8 +80,9 @@ class WriterFactory
     {
         $styleBuilder = new StyleBuilder();
         $optionsManager = new ODS\Manager\OptionsManager($styleBuilder);
+        $styleManager = new StyleManager();
         $generalFactory = new ODS\Creator\InternalFactory(new EntityFactory());
 
-        return new ODS\Writer($optionsManager, $generalFactory);
+        return new ODS\Writer($optionsManager, $styleManager, $generalFactory);
     }
 }
diff --git a/src/Spout/Writer/WriterInterface.php b/src/Spout/Writer/WriterInterface.php
index e2d9f8d..d9dee14 100644
--- a/src/Spout/Writer/WriterInterface.php
+++ b/src/Spout/Writer/WriterInterface.php
@@ -2,6 +2,8 @@
 
 namespace Box\Spout\Writer;
 
+use Box\Spout\Writer\Common\Entity\Style\Style;
+
 /**
  * Interface WriterInterface
  *
@@ -45,7 +47,7 @@ interface WriterInterface
      * @see addRow
      *
      * @param array $dataRow Array of array containing data to be streamed.
-     * @param Style\Style $style Style to be applied to the row.
+     * @param Style $style Style to be applied to the row.
      * @return WriterInterface
      * @throws \Box\Spout\Common\Exception\InvalidArgumentException If the input param is not valid
      * @throws \Box\Spout\Writer\Exception\WriterNotOpenedException If this function is called before opening the writer
@@ -73,7 +75,7 @@ interface WriterInterface
      * @see addRows
      *
      * @param array $dataRows Array of array containing data to be streamed.
-     * @param Style\Style $style Style to be applied to the rows.
+     * @param Style $style Style to be applied to the rows.
      * @return WriterInterface
      * @throws \Box\Spout\Common\Exception\InvalidArgumentException If the input param is not valid
      * @throws \Box\Spout\Writer\Exception\WriterNotOpenedException If this function is called before opening the writer
diff --git a/src/Spout/Writer/WriterMultiSheetsAbstract.php b/src/Spout/Writer/WriterMultiSheetsAbstract.php
index 0784a47..0879580 100644
--- a/src/Spout/Writer/WriterMultiSheetsAbstract.php
+++ b/src/Spout/Writer/WriterMultiSheetsAbstract.php
@@ -5,6 +5,7 @@ namespace Box\Spout\Writer;
 use Box\Spout\Writer\Common\Manager\OptionsManagerInterface;
 use Box\Spout\Writer\Common\Entity\Options;
 use Box\Spout\Writer\Common\Entity\Worksheet;
+use Box\Spout\Writer\Common\Manager\StyleManager;
 use Box\Spout\Writer\Exception\WriterNotOpenedException;
 use Box\Spout\Writer\Common\Creator\InternalFactoryInterface;
 use Box\Spout\Writer\Common\Manager\WorkbookManagerInterface;
@@ -26,11 +27,12 @@ abstract class WriterMultiSheetsAbstract extends WriterAbstract
 
     /**
      * @param OptionsManagerInterface $optionsManager
+     * @param StyleManager $styleManager
      * @param InternalFactoryInterface $internalFactory
      */
-    public function __construct(OptionsManagerInterface $optionsManager, InternalFactoryInterface $internalFactory)
+    public function __construct(OptionsManagerInterface $optionsManager, StyleManager $styleManager, InternalFactoryInterface $internalFactory)
     {
-        parent::__construct($optionsManager);
+        parent::__construct($optionsManager, $styleManager);
         $this->internalFactory = $internalFactory;
     }
 
@@ -151,7 +153,7 @@ abstract class WriterMultiSheetsAbstract extends WriterAbstract
      *
      * @param array $dataRow Array containing data to be written.
      *          Example $dataRow = ['data1', 1234, null, '', 'data5'];
-     * @param \Box\Spout\Writer\Style\Style $style Style to be applied to the row.
+     * @param \Box\Spout\Writer\Common\Entity\Style\Style $style Style to be applied to the row.
      * @return void
      * @throws \Box\Spout\Writer\Exception\WriterNotOpenedException If the book is not created yet
      * @throws \Box\Spout\Common\Exception\IOException If unable to write data
diff --git a/src/Spout/Writer/XLSX/Creator/InternalFactory.php b/src/Spout/Writer/XLSX/Creator/InternalFactory.php
index 301cf33..ca15408 100644
--- a/src/Spout/Writer/XLSX/Creator/InternalFactory.php
+++ b/src/Spout/Writer/XLSX/Creator/InternalFactory.php
@@ -10,6 +10,7 @@ use Box\Spout\Writer\Common\Creator\EntityFactory;
 use Box\Spout\Writer\Common\Creator\InternalFactoryInterface;
 use Box\Spout\Writer\Common\Creator\WorkbookFactory;
 use Box\Spout\Writer\Common\Creator\WorksheetFactory;
+use Box\Spout\Writer\Common\Manager\StyleManager;
 use Box\Spout\Writer\XLSX\Helper\FileSystemHelper;
 use Box\Spout\Writer\XLSX\Helper\SharedStringsHelper;
 use Box\Spout\Writer\XLSX\Helper\StyleHelper;
@@ -102,7 +103,17 @@ class InternalFactory implements InternalFactoryInterface
     private function createStyleHelper(OptionsManagerInterface $optionsManager)
     {
         $defaultRowStyle = $optionsManager->getOption(Options::DEFAULT_ROW_STYLE);
-        return new StyleHelper($defaultRowStyle);
+        $styleManager = $this->createStyleManager();
+
+        return new StyleHelper($defaultRowStyle, $styleManager);
+    }
+
+    /**
+     * @return StyleManager
+     */
+    private function createStyleManager()
+    {
+        return new StyleManager();
     }
 
     /**
diff --git a/src/Spout/Writer/XLSX/Helper/BorderHelper.php b/src/Spout/Writer/XLSX/Helper/BorderHelper.php
index ad63aea..1b0183a 100644
--- a/src/Spout/Writer/XLSX/Helper/BorderHelper.php
+++ b/src/Spout/Writer/XLSX/Helper/BorderHelper.php
@@ -2,8 +2,8 @@
 
 namespace Box\Spout\Writer\XLSX\Helper;
 
-use Box\Spout\Writer\Style\Border;
-use Box\Spout\Writer\Style\BorderPart;
+use Box\Spout\Writer\Common\Entity\Style\Border;
+use Box\Spout\Writer\Common\Entity\Style\BorderPart;
 
 class BorderHelper
 {
diff --git a/src/Spout/Writer/XLSX/Helper/StyleHelper.php b/src/Spout/Writer/XLSX/Helper/StyleHelper.php
index 2795c87..330f8cc 100644
--- a/src/Spout/Writer/XLSX/Helper/StyleHelper.php
+++ b/src/Spout/Writer/XLSX/Helper/StyleHelper.php
@@ -3,8 +3,8 @@
 namespace Box\Spout\Writer\XLSX\Helper;
 
 use Box\Spout\Writer\Common\Helper\StyleHelperAbstract;
-use Box\Spout\Writer\Style\Color;
-use Box\Spout\Writer\Style\Style;
+use Box\Spout\Writer\Common\Entity\Style\Color;
+use Box\Spout\Writer\Common\Entity\Style\Style;
 
 /**
  * Class StyleHelper
@@ -45,8 +45,8 @@ class StyleHelper extends StyleHelperAbstract
     /**
      * XLSX specific operations on the registered styles
      *
-     * @param \Box\Spout\Writer\Style\Style $style
-     * @return \Box\Spout\Writer\Style\Style
+     * @param \Box\Spout\Writer\Common\Entity\Style\Style $style
+     * @return \Box\Spout\Writer\Common\Entity\Style\Style
      */
     public function registerStyle($style)
     {
@@ -59,7 +59,7 @@ class StyleHelper extends StyleHelperAbstract
     /**
      * Register a fill definition
      *
-     * @param \Box\Spout\Writer\Style\Style $style
+     * @param \Box\Spout\Writer\Common\Entity\Style\Style $style
      */
     protected function registerFill($style)
     {
@@ -92,7 +92,7 @@ class StyleHelper extends StyleHelperAbstract
     /**
      * Register a border definition
      *
-     * @param \Box\Spout\Writer\Style\Style $style
+     * @param \Box\Spout\Writer\Common\Entity\Style\Style $style
      */
     protected function registerBorder($style)
     {
@@ -174,7 +174,7 @@ EOD;
     {
         $content = '<fonts count="' . count($this->styleIdToStyleMappingTable) . '">';
 
-        /** @var \Box\Spout\Writer\Style\Style $style */
+        /** @var \Box\Spout\Writer\Common\Entity\Style\Style $style */
         foreach ($this->getRegisteredStyles() as $style) {
             $content .= '<font>';
 
@@ -251,7 +251,7 @@ EOD;
         $content .= '<border><left/><right/><top/><bottom/></border>';
 
         foreach ($this->registeredBorders as $styleId) {
-            /** @var \Box\Spout\Writer\Style\Style $style */
+            /** @var \Box\Spout\Writer\Common\Entity\Style\Style $style */
             $style = $this->styleIdToStyleMappingTable[$styleId];
             $border = $style->getBorder();
             $content .= '<border>';
@@ -261,7 +261,7 @@ EOD;
 
             foreach ($sortOrder as $partName) {
                 if ($border->hasPart($partName)) {
-                    /** @var $part \Box\Spout\Writer\Style\BorderPart */
+                    /** @var $part \Box\Spout\Writer\Common\Entity\Style\BorderPart */
                     $part = $border->getPart($partName);
                     $content .= BorderHelper::serializeBorderPart($part);
                 }
diff --git a/src/Spout/Writer/XLSX/Manager/OptionsManager.php b/src/Spout/Writer/XLSX/Manager/OptionsManager.php
index 5980d91..425f2f6 100644
--- a/src/Spout/Writer/XLSX/Manager/OptionsManager.php
+++ b/src/Spout/Writer/XLSX/Manager/OptionsManager.php
@@ -4,7 +4,7 @@ namespace Box\Spout\Writer\XLSX\Manager;
 
 use Box\Spout\Writer\Common\Entity\Options;
 use Box\Spout\Writer\Common\Manager\OptionsManagerAbstract;
-use Box\Spout\Writer\Style\StyleBuilder;
+use Box\Spout\Writer\Common\Creator\Style\StyleBuilder;
 
 /**
  * Class OptionsManager
diff --git a/src/Spout/Writer/XLSX/Manager/WorksheetManager.php b/src/Spout/Writer/XLSX/Manager/WorksheetManager.php
index 07f5550..ad6753c 100644
--- a/src/Spout/Writer/XLSX/Manager/WorksheetManager.php
+++ b/src/Spout/Writer/XLSX/Manager/WorksheetManager.php
@@ -11,7 +11,7 @@ use Box\Spout\Writer\Common\Entity\Options;
 use Box\Spout\Writer\Common\Entity\Cell;
 use Box\Spout\Writer\Common\Entity\Worksheet;
 use Box\Spout\Writer\Common\Manager\WorksheetManagerInterface;
-use Box\Spout\Writer\Style\Style;
+use Box\Spout\Writer\Common\Entity\Style\Style;
 use Box\Spout\Writer\XLSX\Helper\SharedStringsHelper;
 use Box\Spout\Writer\XLSX\Helper\StyleHelper;
 
@@ -155,7 +155,7 @@ EOD;
      * @param Worksheet $worksheet The worksheet to add the row to
      * @param array $dataRow Array containing data to be written. Cannot be empty.
      *          Example $dataRow = ['data1', 1234, null, '', 'data5'];
-     * @param \Box\Spout\Writer\Style\Style $style Style to be applied to the row. NULL means use default style.
+     * @param \Box\Spout\Writer\Common\Entity\Style\Style $style Style to be applied to the row. NULL means use default style.
      * @return void
      * @throws \Box\Spout\Common\Exception\IOException If the data cannot be written
      * @throws \Box\Spout\Common\Exception\InvalidArgumentException If a cell value's type is not supported
diff --git a/tests/Spout/Writer/Style/BorderTest.php b/tests/Spout/Writer/Common/Entity/Style/BorderTest.php
similarity index 84%
rename from tests/Spout/Writer/Style/BorderTest.php
rename to tests/Spout/Writer/Common/Entity/Style/BorderTest.php
index 181d8cf..e9cd1d2 100644
--- a/tests/Spout/Writer/Style/BorderTest.php
+++ b/tests/Spout/Writer/Common/Entity/Style/BorderTest.php
@@ -1,7 +1,17 @@
 <?php
 
-namespace Box\Spout\Writer\Style;
+namespace Box\Spout\Writer\Common\EntityStyle;
 
+use Box\Spout\Writer\Common\Creator\Style\BorderBuilder;
+use Box\Spout\Writer\Common\Entity\Style\Border;
+use Box\Spout\Writer\Common\Entity\Style\BorderPart;
+use Box\Spout\Writer\Common\Entity\Style\Color;
+
+/**
+ * Class BorderTest
+ *
+ * @package Box\Spout\Writer\Common\EntityStyle
+ */
 class BorderTest extends \PHPUnit_Framework_TestCase
 {
     /**
@@ -20,7 +30,7 @@ class BorderTest extends \PHPUnit_Framework_TestCase
      */
     public function testInvalidBorderPart()
     {
-        $invalidBorderPart = new BorderPart('invalid');
+        new BorderPart('invalid');
     }
 
     /**
@@ -28,7 +38,7 @@ class BorderTest extends \PHPUnit_Framework_TestCase
      */
     public function testInvalidBorderPartStyle()
     {
-        $invalidBorderPartStyle = new BorderPart(Border::LEFT, Color::BLACK, Border::WIDTH_THIN, 'invalid');
+        new BorderPart(Border::LEFT, Color::BLACK, Border::WIDTH_THIN, 'invalid');
     }
 
     /**
@@ -36,7 +46,7 @@ class BorderTest extends \PHPUnit_Framework_TestCase
      */
     public function testInvalidBorderPartWidth()
     {
-        $invalidBorderPartStyle = new BorderPart(Border::LEFT, Color::BLACK, 'invalid', Border::STYLE_DASHED);
+        new BorderPart(Border::LEFT, Color::BLACK, 'invalid', Border::STYLE_DASHED);
     }
 
     /**
diff --git a/tests/Spout/Writer/Style/ColorTest.php b/tests/Spout/Writer/Common/Entity/Style/ColorTest.php
similarity index 95%
rename from tests/Spout/Writer/Style/ColorTest.php
rename to tests/Spout/Writer/Common/Entity/Style/ColorTest.php
index 7dd4587..34ffe24 100644
--- a/tests/Spout/Writer/Style/ColorTest.php
+++ b/tests/Spout/Writer/Common/Entity/Style/ColorTest.php
@@ -1,11 +1,11 @@
 <?php
 
-namespace Box\Spout\Writer\Style;
+namespace Box\Spout\Writer\Common\Entity\Style;
 
 /**
  * Class ColorTest
  *
- * @package Box\Spout\Writer\Style
+ * @package Box\Spout\Writer\Common\Entity\Style
  */
 class ColorTest extends \PHPUnit_Framework_TestCase
 {
diff --git a/tests/Spout/Writer/Style/StyleTest.php b/tests/Spout/Writer/Common/Manager/StyleManagerTest.php
similarity index 67%
rename from tests/Spout/Writer/Style/StyleTest.php
rename to tests/Spout/Writer/Common/Manager/StyleManagerTest.php
index 7d3ec36..a1b9525 100644
--- a/tests/Spout/Writer/Style/StyleTest.php
+++ b/tests/Spout/Writer/Common/Manager/StyleManagerTest.php
@@ -1,14 +1,31 @@
 <?php
 
-namespace Box\Spout\Writer\Style;
+namespace Box\Spout\Writer\Common\Manager;
+
+use Box\Spout\Writer\Common\Creator\Style\BorderBuilder;
+use Box\Spout\Writer\Common\Creator\Style\StyleBuilder;
+use Box\Spout\Writer\Common\Entity\Style\Border;
+use Box\Spout\Writer\Common\Entity\Style\Color;
+use Box\Spout\Writer\Common\Entity\Style\Style;
 
 /**
- * Class StyleTest
+ * Class StyleManagerTest
  *
- * @package Box\Spout\Writer\Style
+ * @package Box\Spout\Writer\Common\Manager
  */
-class StyleTest extends \PHPUnit_Framework_TestCase
+class StyleManagerTest extends \PHPUnit_Framework_TestCase
 {
+    /** @var StyleManager */
+    private $styleManager;
+
+    /**
+     * @return void
+     */
+    public function setUp()
+    {
+        $this->styleManager = new StyleManager();
+    }
+
     /**
      * @return void
      */
@@ -20,7 +37,7 @@ class StyleTest extends \PHPUnit_Framework_TestCase
         $style2 = (new StyleBuilder())->setFontBold()->build();
         $style2->setId(2);
 
-        $this->assertEquals($style1->serialize(), $style2->serialize());
+        $this->assertEquals($this->styleManager->serialize($style1), $this->styleManager->serialize($style2));
     }
 
     /**
@@ -30,7 +47,7 @@ class StyleTest extends \PHPUnit_Framework_TestCase
     {
         $baseStyle = (new StyleBuilder())->build();
         $currentStyle = (new StyleBuilder())->build();
-        $mergedStyle = $currentStyle->mergeWith($baseStyle);
+        $mergedStyle = $this->styleManager->merge($currentStyle, $baseStyle);
 
         $this->assertNotSame($mergedStyle, $currentStyle);
     }
@@ -42,7 +59,7 @@ class StyleTest extends \PHPUnit_Framework_TestCase
     {
         $baseStyle = (new StyleBuilder())->setFontSize(99)->setFontBold()->build();
         $currentStyle = (new StyleBuilder())->setFontName('Font')->setFontUnderline()->build();
-        $mergedStyle = $currentStyle->mergeWith($baseStyle);
+        $mergedStyle = $this->styleManager->merge($currentStyle, $baseStyle);
 
         $this->assertNotEquals(99, $currentStyle->getFontSize());
         $this->assertFalse($currentStyle->isFontBold());
@@ -60,7 +77,7 @@ class StyleTest extends \PHPUnit_Framework_TestCase
     {
         $baseStyle = (new StyleBuilder())->setFontSize(10)->build();
         $currentStyle = (new StyleBuilder())->setFontSize(99)->build();
-        $mergedStyle = $currentStyle->mergeWith($baseStyle);
+        $mergedStyle = $this->styleManager->merge($currentStyle, $baseStyle);
 
         $this->assertEquals(99, $mergedStyle->getFontSize());
     }
@@ -72,7 +89,7 @@ class StyleTest extends \PHPUnit_Framework_TestCase
     {
         $baseStyle = (new StyleBuilder())->build();
         $currentStyle = (new StyleBuilder())->setFontItalic()->setFontStrikethrough()->build();
-        $mergedStyle = $currentStyle->mergeWith($baseStyle);
+        $mergedStyle = $this->styleManager->merge($currentStyle, $baseStyle);
 
         $this->assertFalse($baseStyle->isFontItalic());
         $this->assertFalse($baseStyle->isFontStrikethrough());
@@ -93,7 +110,7 @@ class StyleTest extends \PHPUnit_Framework_TestCase
             ->setShouldWrapText()
             ->build();
         $currentStyle = (new StyleBuilder())->build();
-        $mergedStyle = $currentStyle->mergeWith($baseStyle);
+        $mergedStyle = $this->styleManager->merge($currentStyle, $baseStyle);
 
         $this->assertFalse($currentStyle->isFontUnderline());
         $this->assertTrue($mergedStyle->isFontUnderline());
@@ -109,10 +126,10 @@ class StyleTest extends \PHPUnit_Framework_TestCase
     {
         $baseStyle = (new StyleBuilder())->build();
         $currentStyle = (new StyleBuilder())->build();
-        $mergedStyle = $currentStyle->mergeWith($baseStyle);
+        $mergedStyle = $this->styleManager->merge($currentStyle, $baseStyle);
 
-        $this->assertTrue($baseStyle->serialize() === $currentStyle->serialize());
-        $this->assertTrue($currentStyle->serialize() === $mergedStyle->serialize());
+        $this->assertTrue($this->styleManager->serialize($baseStyle) === $this->styleManager->serialize($currentStyle));
+        $this->assertTrue($this->styleManager->serialize($currentStyle) === $this->styleManager->serialize($mergedStyle));
     }
 
     /**
@@ -125,9 +142,9 @@ class StyleTest extends \PHPUnit_Framework_TestCase
             ->setFontSize(Style::DEFAULT_FONT_SIZE)
             ->build();
         $currentStyle = (new StyleBuilder())->build();
-        $mergedStyle = $currentStyle->mergeWith($baseStyle);
+        $mergedStyle = $this->styleManager->merge($currentStyle, $baseStyle);
 
-        $this->assertTrue($currentStyle->serialize() === $mergedStyle->serialize());
+        $this->assertTrue($this->styleManager->serialize($currentStyle) === $this->styleManager->serialize($mergedStyle));
     }
 
     /**
@@ -151,10 +168,10 @@ class StyleTest extends \PHPUnit_Framework_TestCase
 
         $baseStyle = (new StyleBuilder())->setBorder($border)->build();
         $currentStyle = (new StyleBuilder())->build();
-        $mergedStyle = $currentStyle->mergeWith($baseStyle);
+        $mergedStyle = $this->styleManager->merge($currentStyle, $baseStyle);
 
         $this->assertEquals(null, $currentStyle->getBorder(), 'Current style has no border');
-        $this->assertInstanceOf('Box\Spout\Writer\Style\Border', $baseStyle->getBorder(), 'Base style has a border');
-        $this->assertInstanceOf('Box\Spout\Writer\Style\Border', $mergedStyle->getBorder(), 'Merged style has a border');
+        $this->assertInstanceOf('Box\Spout\Writer\Common\Entity\Style\Border', $baseStyle->getBorder(), 'Base style has a border');
+        $this->assertInstanceOf('Box\Spout\Writer\Common\Entity\Style\Border', $mergedStyle->getBorder(), 'Merged style has a border');
     }
 }
diff --git a/tests/Spout/Writer/ODS/Helper/StyleHelperTest.php b/tests/Spout/Writer/ODS/Helper/StyleHelperTest.php
index 763f904..4fc68ae 100644
--- a/tests/Spout/Writer/ODS/Helper/StyleHelperTest.php
+++ b/tests/Spout/Writer/ODS/Helper/StyleHelperTest.php
@@ -2,7 +2,9 @@
 
 namespace Box\Spout\Writer\ODS\Helper;
 
-use Box\Spout\Writer\Style\StyleBuilder;
+use Box\Spout\Writer\Common\Creator\Style\StyleBuilder;
+use Box\Spout\Writer\Common\Entity\Style\Style;
+use Box\Spout\Writer\Common\Manager\StyleManager;
 
 /**
  * Class StyleHelperTest
@@ -11,15 +13,19 @@ use Box\Spout\Writer\Style\StyleBuilder;
  */
 class StyleHelperTest extends \PHPUnit_Framework_TestCase
 {
-    /** @var \Box\Spout\Writer\Style\Style */
+    /** @var Style */
     protected $defaultStyle;
 
+    /** @var StyleHelper */
+    private $styleHelper;
+
     /**
      * @return void
      */
     public function setUp()
     {
         $this->defaultStyle = (new StyleBuilder())->build();
+        $this->styleHelper = new StyleHelper($this->defaultStyle, new StyleManager());
     }
 
     /**
@@ -34,9 +40,8 @@ class StyleHelperTest extends \PHPUnit_Framework_TestCase
         $this->assertNull($style1->getId());
         $this->assertNull($style2->getId());
 
-        $styleHelper = new StyleHelper($this->defaultStyle);
-        $registeredStyle1 = $styleHelper->registerStyle($style1);
-        $registeredStyle2 = $styleHelper->registerStyle($style2);
+        $registeredStyle1 = $this->styleHelper->registerStyle($style1);
+        $registeredStyle2 = $this->styleHelper->registerStyle($style2);
 
         $this->assertEquals(1, $registeredStyle1->getId());
         $this->assertEquals(2, $registeredStyle2->getId());
@@ -49,9 +54,8 @@ class StyleHelperTest extends \PHPUnit_Framework_TestCase
     {
         $style = (new StyleBuilder())->setFontBold()->build();
 
-        $styleHelper = new StyleHelper($this->defaultStyle);
-        $registeredStyle1 = $styleHelper->registerStyle($style);
-        $registeredStyle2 = $styleHelper->registerStyle($style);
+        $registeredStyle1 = $this->styleHelper->registerStyle($style);
+        $registeredStyle2 = $this->styleHelper->registerStyle($style);
 
         $this->assertEquals(1, $registeredStyle1->getId());
         $this->assertEquals(1, $registeredStyle2->getId());
@@ -63,11 +67,10 @@ class StyleHelperTest extends \PHPUnit_Framework_TestCase
     public function testApplyExtraStylesIfNeededShouldApplyWrapTextIfCellContainsNewLine()
     {
         $style = clone $this->defaultStyle;
-        $styleHelper = new StyleHelper($this->defaultStyle);
 
         $this->assertFalse($style->shouldWrapText());
 
-        $updatedStyle = $styleHelper->applyExtraStylesIfNeeded($style, [12, 'single line', "multi\nlines", null]);
+        $updatedStyle = $this->styleHelper->applyExtraStylesIfNeeded($style, [12, 'single line', "multi\nlines", null]);
 
         $this->assertTrue($updatedStyle->shouldWrapText());
     }
@@ -78,11 +81,10 @@ class StyleHelperTest extends \PHPUnit_Framework_TestCase
     public function testApplyExtraStylesIfNeededShouldDoNothingIfWrapTextAlreadyApplied()
     {
         $style = (new StyleBuilder())->setShouldWrapText()->build();
-        $styleHelper = new StyleHelper($this->defaultStyle);
 
         $this->assertTrue($style->shouldWrapText());
 
-        $updatedStyle = $styleHelper->applyExtraStylesIfNeeded($style, ["multi\nlines"]);
+        $updatedStyle = $this->styleHelper->applyExtraStylesIfNeeded($style, ["multi\nlines"]);
 
         $this->assertTrue($updatedStyle->shouldWrapText());
     }
diff --git a/tests/Spout/Writer/ODS/WriterWithStyleTest.php b/tests/Spout/Writer/ODS/WriterWithStyleTest.php
index b472055..a2eaf0c 100644
--- a/tests/Spout/Writer/ODS/WriterWithStyleTest.php
+++ b/tests/Spout/Writer/ODS/WriterWithStyleTest.php
@@ -6,11 +6,11 @@ use Box\Spout\Common\Type;
 use Box\Spout\Reader\Wrapper\XMLReader;
 use Box\Spout\TestUsingResource;
 use Box\Spout\Writer\ODS\Helper\BorderHelper;
-use Box\Spout\Writer\Style\Border;
-use Box\Spout\Writer\Style\BorderBuilder;
-use Box\Spout\Writer\Style\Color;
-use Box\Spout\Writer\Style\Style;
-use Box\Spout\Writer\Style\StyleBuilder;
+use Box\Spout\Writer\Common\Entity\Style\Border;
+use Box\Spout\Writer\Common\Creator\Style\BorderBuilder;
+use Box\Spout\Writer\Common\Entity\Style\Color;
+use Box\Spout\Writer\Common\Entity\Style\Style;
+use Box\Spout\Writer\Common\Creator\Style\StyleBuilder;
 use Box\Spout\Writer\WriterFactory;
 
 /**
@@ -22,7 +22,7 @@ class WriterWithStyleTest extends \PHPUnit_Framework_TestCase
 {
     use TestUsingResource;
 
-    /** @var \Box\Spout\Writer\Style\Style */
+    /** @var \Box\Spout\Writer\Common\Entity\Style\Style */
     protected $defaultStyle;
 
     /**
@@ -67,7 +67,7 @@ class WriterWithStyleTest extends \PHPUnit_Framework_TestCase
      * @dataProvider dataProviderForInvalidStyle
      * @expectedException \Box\Spout\Common\Exception\InvalidArgumentException
      *
-     * @param \Box\Spout\Writer\Style\Style $style
+     * @param \Box\Spout\Writer\Common\Entity\Style\Style $style
      */
     public function testAddRowWithStyleShouldThrowExceptionIfInvalidStyleGiven($style)
     {
@@ -84,7 +84,7 @@ class WriterWithStyleTest extends \PHPUnit_Framework_TestCase
      * @dataProvider dataProviderForInvalidStyle
      * @expectedException \Box\Spout\Common\Exception\InvalidArgumentException
      *
-     * @param \Box\Spout\Writer\Style\Style $style
+     * @param \Box\Spout\Writer\Common\Entity\Style\Style $style
      */
     public function testAddRowsWithStyleShouldThrowExceptionIfInvalidStyleGiven($style)
     {
@@ -346,7 +346,7 @@ class WriterWithStyleTest extends \PHPUnit_Framework_TestCase
     /**
      * @param array $allRows
      * @param string $fileName
-     * @param \Box\Spout\Writer\Style\Style $style
+     * @param \Box\Spout\Writer\Common\Entity\Style\Style $style
      * @return Writer
      */
     private function writeToODSFile($allRows, $fileName, $style)
@@ -367,7 +367,7 @@ class WriterWithStyleTest extends \PHPUnit_Framework_TestCase
     /**
      * @param array $allRows
      * @param string $fileName
-     * @param \Box\Spout\Writer\Style\Style|null $defaultStyle
+     * @param \Box\Spout\Writer\Common\Entity\Style\Style|null $defaultStyle
      * @return Writer
      */
     private function writeToODSFileWithDefaultStyle($allRows, $fileName, $defaultStyle)
@@ -389,7 +389,7 @@ class WriterWithStyleTest extends \PHPUnit_Framework_TestCase
     /**
      * @param array $allRows
      * @param string $fileName
-     * @param \Box\Spout\Writer\Style\Style|null[] $styles
+     * @param \Box\Spout\Writer\Common\Entity\Style\Style|null[] $styles
      * @return Writer
      */
     private function writeToODSFileWithMultipleStyles($allRows, $fileName, $styles)
diff --git a/tests/Spout/Writer/XLSX/Helper/StyleHelperTest.php b/tests/Spout/Writer/XLSX/Helper/StyleHelperTest.php
index bcf9344..3cfc7b2 100644
--- a/tests/Spout/Writer/XLSX/Helper/StyleHelperTest.php
+++ b/tests/Spout/Writer/XLSX/Helper/StyleHelperTest.php
@@ -2,10 +2,12 @@
 
 namespace Box\Spout\Writer\XLSX\Helper;
 
-use Box\Spout\Writer\Style\Border;
-use Box\Spout\Writer\Style\BorderBuilder;
-use Box\Spout\Writer\Style\Color;
-use Box\Spout\Writer\Style\StyleBuilder;
+use Box\Spout\Writer\Common\Entity\Style\Border;
+use Box\Spout\Writer\Common\Creator\Style\BorderBuilder;
+use Box\Spout\Writer\Common\Entity\Style\Color;
+use Box\Spout\Writer\Common\Creator\Style\StyleBuilder;
+use Box\Spout\Writer\Common\Entity\Style\Style;
+use Box\Spout\Writer\Common\Manager\StyleManager;
 
 /**
  * Class StyleHelperTest
@@ -14,15 +16,19 @@ use Box\Spout\Writer\Style\StyleBuilder;
  */
 class StyleHelperTest extends \PHPUnit_Framework_TestCase
 {
-    /** @var \Box\Spout\Writer\Style\Style */
+    /** @var Style */
     protected $defaultStyle;
 
+    /** @var StyleHelper */
+    private $styleHelper;
+
     /**
      * @return void
      */
     public function setUp()
     {
         $this->defaultStyle = (new StyleBuilder())->build();
+        $this->styleHelper = new StyleHelper($this->defaultStyle, new StyleManager());
     }
 
     /**
@@ -37,9 +43,8 @@ class StyleHelperTest extends \PHPUnit_Framework_TestCase
         $this->assertNull($style1->getId());
         $this->assertNull($style2->getId());
 
-        $styleHelper = new StyleHelper($this->defaultStyle);
-        $registeredStyle1 = $styleHelper->registerStyle($style1);
-        $registeredStyle2 = $styleHelper->registerStyle($style2);
+        $registeredStyle1 = $this->styleHelper->registerStyle($style1);
+        $registeredStyle2 = $this->styleHelper->registerStyle($style2);
 
         $this->assertEquals(1, $registeredStyle1->getId());
         $this->assertEquals(2, $registeredStyle2->getId());
@@ -52,9 +57,8 @@ class StyleHelperTest extends \PHPUnit_Framework_TestCase
     {
         $style = (new StyleBuilder())->setFontBold()->build();
 
-        $styleHelper = new StyleHelper($this->defaultStyle);
-        $registeredStyle1 = $styleHelper->registerStyle($style);
-        $registeredStyle2 = $styleHelper->registerStyle($style);
+        $registeredStyle1 = $this->styleHelper->registerStyle($style);
+        $registeredStyle2 = $this->styleHelper->registerStyle($style);
 
         $this->assertEquals(1, $registeredStyle1->getId());
         $this->assertEquals(1, $registeredStyle2->getId());
@@ -71,14 +75,13 @@ class StyleHelperTest extends \PHPUnit_Framework_TestCase
         $border = (new BorderBuilder())->setBorderBottom(Color::GREEN)->build();
         $styleWithBorder = (new StyleBuilder())->setBorder($border)->build();
 
-        $styleHelper = new StyleHelper($this->defaultStyle);
-        $styleHelper->registerStyle($styleWithFont);
-        $styleHelper->registerStyle($styleWithBackground);
-        $styleHelper->registerStyle($styleWithBorder);
+        $this->styleHelper->registerStyle($styleWithFont);
+        $this->styleHelper->registerStyle($styleWithBackground);
+        $this->styleHelper->registerStyle($styleWithBorder);
 
-        $this->assertFalse($styleHelper->shouldApplyStyleOnEmptyCell($styleWithFont->getId()));
-        $this->assertTrue($styleHelper->shouldApplyStyleOnEmptyCell($styleWithBackground->getId()));
-        $this->assertTrue($styleHelper->shouldApplyStyleOnEmptyCell($styleWithBorder->getId()));
+        $this->assertFalse($this->styleHelper->shouldApplyStyleOnEmptyCell($styleWithFont->getId()));
+        $this->assertTrue($this->styleHelper->shouldApplyStyleOnEmptyCell($styleWithBackground->getId()));
+        $this->assertTrue($this->styleHelper->shouldApplyStyleOnEmptyCell($styleWithBorder->getId()));
     }
 
     /**
@@ -87,11 +90,10 @@ class StyleHelperTest extends \PHPUnit_Framework_TestCase
     public function testApplyExtraStylesIfNeededShouldApplyWrapTextIfCellContainsNewLine()
     {
         $style = clone $this->defaultStyle;
-        $styleHelper = new StyleHelper($this->defaultStyle);
 
         $this->assertFalse($style->shouldWrapText());
 
-        $updatedStyle = $styleHelper->applyExtraStylesIfNeeded($style, [12, 'single line', "multi\nlines", null]);
+        $updatedStyle = $this->styleHelper->applyExtraStylesIfNeeded($style, [12, 'single line', "multi\nlines", null]);
 
         $this->assertTrue($updatedStyle->shouldWrapText());
     }
@@ -102,11 +104,10 @@ class StyleHelperTest extends \PHPUnit_Framework_TestCase
     public function testApplyExtraStylesIfNeededShouldDoNothingIfWrapTextAlreadyApplied()
     {
         $style = (new StyleBuilder())->setShouldWrapText()->build();
-        $styleHelper = new StyleHelper($this->defaultStyle);
 
         $this->assertTrue($style->shouldWrapText());
 
-        $updatedStyle = $styleHelper->applyExtraStylesIfNeeded($style, ["multi\nlines"]);
+        $updatedStyle = $this->styleHelper->applyExtraStylesIfNeeded($style, ["multi\nlines"]);
 
         $this->assertTrue($updatedStyle->shouldWrapText());
     }
diff --git a/tests/Spout/Writer/XLSX/WriterWithStyleTest.php b/tests/Spout/Writer/XLSX/WriterWithStyleTest.php
index fd66796..2563d69 100644
--- a/tests/Spout/Writer/XLSX/WriterWithStyleTest.php
+++ b/tests/Spout/Writer/XLSX/WriterWithStyleTest.php
@@ -5,11 +5,12 @@ namespace Box\Spout\Writer\XLSX;
 use Box\Spout\Common\Type;
 use Box\Spout\Reader\Wrapper\XMLReader;
 use Box\Spout\TestUsingResource;
-use Box\Spout\Writer\Style\Border;
-use Box\Spout\Writer\Style\BorderBuilder;
-use Box\Spout\Writer\Style\Color;
-use Box\Spout\Writer\Style\Style;
-use Box\Spout\Writer\Style\StyleBuilder;
+use Box\Spout\Writer\Common\Entity\Style\Border;
+use Box\Spout\Writer\Common\Creator\Style\BorderBuilder;
+use Box\Spout\Writer\Common\Entity\Style\Color;
+use Box\Spout\Writer\Common\Entity\Style\Style;
+use Box\Spout\Writer\Common\Creator\Style\StyleBuilder;
+use Box\Spout\Writer\Common\Manager\StyleManager;
 use Box\Spout\Writer\WriterFactory;
 use Box\Spout\Writer\XLSX\Manager\OptionsManager;
 
@@ -22,7 +23,7 @@ class WriterWithStyleTest extends \PHPUnit_Framework_TestCase
 {
     use TestUsingResource;
 
-    /** @var \Box\Spout\Writer\Style\Style */
+    /** @var \Box\Spout\Writer\Common\Entity\Style\Style */
     protected $defaultStyle;
 
     /**
@@ -67,7 +68,7 @@ class WriterWithStyleTest extends \PHPUnit_Framework_TestCase
      * @dataProvider dataProviderForInvalidStyle
      * @expectedException \Box\Spout\Common\Exception\InvalidArgumentException
      *
-     * @param \Box\Spout\Writer\Style\Style $style
+     * @param \Box\Spout\Writer\Common\Entity\Style\Style $style
      */
     public function testAddRowWithStyleShouldThrowExceptionIfInvalidStyleGiven($style)
     {
@@ -84,7 +85,7 @@ class WriterWithStyleTest extends \PHPUnit_Framework_TestCase
      * @dataProvider dataProviderForInvalidStyle
      * @expectedException \Box\Spout\Common\Exception\InvalidArgumentException
      *
-     * @param \Box\Spout\Writer\Style\Style $style
+     * @param \Box\Spout\Writer\Common\Entity\Style\Style $style
      */
     public function testAddRowsWithStyleShouldThrowExceptionIfInvalidStyleGiven($style)
     {
@@ -462,7 +463,7 @@ class WriterWithStyleTest extends \PHPUnit_Framework_TestCase
         $fontStyle = (new StyleBuilder())->setFontBold()->build();
         $emptyStyle = (new StyleBuilder())->build();
 
-        $borderRightFontBoldStyle = $borderRightStyle->mergeWith($fontStyle);
+        $borderRightFontBoldStyle = (new StyleManager())->merge($borderRightStyle, $fontStyle);
 
         $dataRows = [
             ['Border-Left'],
@@ -517,7 +518,7 @@ class WriterWithStyleTest extends \PHPUnit_Framework_TestCase
     /**
      * @param array $allRows
      * @param string $fileName
-     * @param \Box\Spout\Writer\Style\Style $style
+     * @param \Box\Spout\Writer\Common\Entity\Style\Style $style
      * @return Writer
      */
     private function writeToXLSXFile($allRows, $fileName, $style)
@@ -539,7 +540,7 @@ class WriterWithStyleTest extends \PHPUnit_Framework_TestCase
     /**
      * @param array $allRows
      * @param string $fileName
-     * @param \Box\Spout\Writer\Style\Style|null $defaultStyle
+     * @param \Box\Spout\Writer\Common\Entity\Style\Style|null $defaultStyle
      * @return Writer
      */
     private function writeToXLSXFileWithDefaultStyle($allRows, $fileName, $defaultStyle)
@@ -562,7 +563,7 @@ class WriterWithStyleTest extends \PHPUnit_Framework_TestCase
     /**
      * @param array $allRows
      * @param string $fileName
-     * @param \Box\Spout\Writer\Style\Style|null[] $styles
+     * @param \Box\Spout\Writer\Common\Entity\Style\Style|null[] $styles
      * @return Writer
      */
     private function writeToXLSXFileWithMultipleStyles($allRows, $fileName, $styles)