src/java.desktop/share/classes/java/awt/image/IndexColorModel.java

@@ -26,10 +26,12 @@
 package java.awt.image;
 
 import java.awt.Transparency;
 import java.awt.color.ColorSpace;
 import java.math.BigInteger;
+import java.util.Arrays;
+import java.util.Objects;
 
 /**
  * The {@code IndexColorModel} class is a {@code ColorModel}
  * class that works with pixel values consisting of a
  * single sample that is an index into a fixed colormap in the default

@@ -1530,6 +1532,79 @@
                          + " transIndex   = "+transparent_index
                          + " has alpha = "+supportsAlpha
                          + " isAlphaPre = "+isAlphaPremultiplied
                          );
     }
+
+    /**
+     * Tests if the specified {@code Object} is an instance
+     * of {@code IndexColorModel} and equals this
+     * {@code IndexColorModel}.
+     * @param obj the {@code Object} to test for equality
+     * @return {@code true} if the specified {@code Object}
+     * is an instance of {@code IndexColorModel} and equals this
+     * {@code IndexColorModel}; {@code false} otherwise.
+     */
+    @Override
+    public boolean equals(Object obj) {
+
+        IndexColorModel cm = (IndexColorModel) obj;
+        if (this == cm) {
+            return true;
+        }
+
+        if (!super.equals(obj)) {
+            return false;
+        }
+
+        if (map_size != cm.map_size ||
+            transparent_index != cm.transparent_index)
+        {
+            return false;
+        }
+
+        // verify whether we have to check equality of all bits in validBits
+        boolean testValidBits;
+        if (validBits == cm.validBits) {
+            testValidBits = false;
+        } else if (validBits == null || cm.validBits == null) {
+            return false;
+        } else if (validBits.equals(cm.validBits)) {
+            testValidBits = false;
+        } else {
+            testValidBits = true;
+        }
+
+        if (testValidBits) {
+            for (int i = 0; i < map_size; i++) {
+                if (rgb[i] != cm.rgb[i] ||
+                    validBits.testBit(i) != cm.validBits.testBit(i))
+                {
+                    return false;
+                }
+            }
+        } else {
+            for (int i = 0; i < map_size; i++) {
+                if (rgb[i] != cm.rgb[i]) {
+                    return false;
+                }
+            }
+        }
+        return true;
+    }
+
+    /**
+     * Returns the hash code for IndexColorModel.
+     *
+     * @return    a hash code for IndexColorModel
+     */
+    @Override
+    public int hashCode() {
+        int hash = 7;
+        hash = 43 * hash + super.hashCode();
+        hash = 43 * hash + Arrays.hashCode(this.rgb);
+        hash = 43 * hash + this.map_size;
+        hash = 43 * hash + this.transparent_index;
+        hash = 43 * hash + Objects.hashCode(this.validBits);
+        return hash;
+    }
 }