Cover several layout properties with documentation

DEVSIX-6639

Author: AnhelinaM

layout/src/main/java/com/itextpdf/layout/properties/BackgroundImage.java

@@ -48,6 +48,9 @@ This file is part of the iText (R) project.
 import com.itextpdf.kernel.pdf.xobject.PdfXObject;
 import com.itextpdf.layout.properties.BackgroundRepeat.BackgroundRepeatValue;
 
+/**
+ * Class to hold background-image property.
+ */
 public class BackgroundImage {
 
     private static final BlendMode DEFAULT_BLEND_MODE = BlendMode.NORMAL;
@@ -84,10 +87,20 @@ public BackgroundImage(BackgroundImage backgroundImage) {
                 backgroundImage.getBackgroundOrigin());
     }
 
+    /**
+     * Gets initial image if it is instanceof {@link PdfImageXObject}, otherwise returns null.
+     *
+     * @return {@link PdfImageXObject}
+     */
     public PdfImageXObject getImage() {
         return image instanceof PdfImageXObject ? (PdfImageXObject) image : null;
     }
 
+    /**
+     * Gets initial image if it is instanceof {@link PdfFormXObject}, otherwise returns null.
+     *
+     * @return {@link PdfFormXObject}
+     */
     public PdfFormXObject getForm() {
         return image instanceof PdfFormXObject ? (PdfFormXObject) image : null;
     }
@@ -128,10 +141,20 @@ public BackgroundPosition getBackgroundPosition() {
         return position;
     }
 
+    /**
+     * Gets linearGradientBuilder.
+     *
+     * @return {@link AbstractLinearGradientBuilder}
+     */
     public AbstractLinearGradientBuilder getLinearGradientBuilder() {
         return this.linearGradientBuilder;
     }
 
+    /**
+     * Returns is background specified.
+     *
+     * @return {@code true} if background is specified, otherwise false
+     */
     public boolean isBackgroundSpecified() {
         return image instanceof PdfFormXObject || image instanceof PdfImageXObject || linearGradientBuilder != null;
     }
@@ -213,6 +236,9 @@ public static class Builder {
         private BackgroundBox clip = BackgroundBox.BORDER_BOX;
         private BackgroundBox origin = BackgroundBox.PADDING_BOX;
 
+        /**
+         * Creates a new {@link Builder} instance.
+         */
         public Builder() {
         }
 

layout/src/main/java/com/itextpdf/layout/properties/BackgroundPosition.java

@@ -239,12 +239,18 @@ private static float calculateValue(UnitValue value, float fullValue) {
         return value.isPercentValue() ? (value.getValue() / 100 * fullValue) : value.getValue();
     }
 
+    /**
+     * A specialized enum containing positions in x-dimension (horizontal positions).
+     */
     public static enum PositionX {
         LEFT,
         RIGHT,
         CENTER
     }
 
+    /**
+     * A specialized enum containing positions in y-dimension (vertical positions).
+     */
     public static enum PositionY {
         TOP,
         BOTTOM,

layout/src/main/java/com/itextpdf/layout/properties/BackgroundSize.java

@@ -44,6 +44,10 @@ public class BackgroundSize {
      */
     private boolean contain;
 
+    /**
+     * Creates a new {@link BackgroundSize} instance.
+     * The "cover" and "contain" properties are not set.
+     */
     public BackgroundSize() {
         cover = false;
         contain = false;

layout/src/main/java/com/itextpdf/layout/properties/ListSymbolPosition.java

@@ -42,6 +42,9 @@ This file is part of the iText (R) project.
  */
 package com.itextpdf.layout.properties;
 
+/**
+ * A specialized enum containing position properties for list symbols.
+ */
 public enum ListSymbolPosition {
     DEFAULT,
     INSIDE,

layout/src/main/java/com/itextpdf/layout/properties/OverflowWrapPropertyValue.java

@@ -23,6 +23,17 @@ This file is part of the iText (R) project.
 
 package com.itextpdf.layout.properties;
 
+/**
+ * The possible values for the overflow wrap property.
+ *
+ * <p>
+ * {@link OverflowWrapPropertyValue#ANYWHERE} and {@link OverflowWrapPropertyValue#BREAK_WORD}
+ * mean that long words will break if they overflow the container.
+ *
+ * <p>
+ * {@link OverflowWrapPropertyValue#NORMAL} means that long words will not break,
+ * even if they overflow the container.
+ */
 public enum OverflowWrapPropertyValue {
     ANYWHERE,
     BREAK_WORD,

layout/src/main/java/com/itextpdf/layout/properties/TransparentColor.java

@@ -46,33 +46,63 @@ This file is part of the iText (R) project.
 import com.itextpdf.kernel.pdf.canvas.PdfCanvas;
 import com.itextpdf.kernel.pdf.extgstate.PdfExtGState;
 
+/**
+ * Represents a color with the specified opacity.
+ */
 public class TransparentColor {
     private Color color;
     private float opacity;
-    
+
+    /**
+     * Creates a new {@link TransparentColor} instance of certain fully opaque color.
+     *
+     * @param color the {@link Color} of the created {@link TransparentColor} object
+     */
     public TransparentColor(Color color) {
         this.color = color;
         this.opacity = 1f;
     }
-    
+
+    /**
+     * Creates a new {@link TransparentColor}.
+     *
+     * @param color the {@link Color} of the created {@link TransparentColor} object
+     * @param opacity a float defining the opacity of the color; a float between 0 and 1,
+     *                where 1 stands for fully opaque color and 0 - for fully transparent
+     */
     public TransparentColor(Color color, float opacity) {
         this.color = color;
         this.opacity = opacity;
     }
 
+    /**
+     * Gets the color.
+     * @return a {@link Color}
+     */
     public Color getColor() {
         return color;
     }
 
+    /**
+     * Gets the opacity of color.
+     * @return a float between 0 and 1, where 1 stands for fully opaque color and 0 - for fully transparent
+     */
     public float getOpacity() {
         return opacity;
     }
 
+    /**
+     * Sets the opacity value for <b>non-stroking</b> operations in the transparent imaging model.
+     * @param canvas the {@link PdfCanvas} to be written to
+     */
     public void applyFillTransparency(PdfCanvas canvas) {
         applyTransparency(canvas, false);
-
     }
 
+    /**
+     * Sets the opacity value for <b>stroking</b> operations in the transparent imaging model.
+     * @param canvas the {@link PdfCanvas} to be written to
+     */
     public void applyStrokeTransparency(PdfCanvas canvas) {
         applyTransparency(canvas, true);        
     }