#651: Fix ExtraSamplesColorModel equals + hashcode to behave nicely with ImageTypeSpecifier comparison.

(cherry picked from commit 98e4b762067344dc23fd3e30ee7e6cf9e143f950)

imageio/imageio-tiff/src/main/java/com/twelvemonkeys/imageio/plugins/tiff/ExtraSamplesColorModel.java

@@ -35,6 +35,7 @@ import com.twelvemonkeys.lang.Validate;
 import java.awt.*;
 import java.awt.color.ColorSpace;
 import java.awt.image.*;
+import java.util.Objects;
 
 import static java.awt.image.DataBuffer.getDataTypeSize;
 
@@ -119,4 +120,44 @@ final class ExtraSamplesColorModel extends ComponentColorModel {
 
         throw new IllegalArgumentException("This method has not been implemented for transferType " + transferType);
     }
+
+    @Override
+    public boolean equals(final Object other) {
+        if (this == other) {
+            return true;
+        }
+        if (other == null || getClass() != other.getClass()) {
+            return false;
+        }
+
+        ExtraSamplesColorModel that = (ExtraSamplesColorModel) other;
+
+        if (hasAlpha() != that.hasAlpha() ||
+                isAlphaPremultiplied() != that.isAlphaPremultiplied() ||
+                getPixelSize() != that.getPixelSize() ||
+                getTransparency() != that.getTransparency() ||
+                numComponents != that.numComponents) {
+            return false;
+        }
+
+        int[] nBits = getComponentSize();
+        int[] nb = that.getComponentSize();
+
+        if ((nBits == null) || (nb == null)) {
+            return ((nBits == null) && (nb == null));
+        }
+
+        for (int i = 0; i < nBits.length; i++) {
+            if (nBits[i] != nb[i]) {
+                return false;
+            }
+        }
+
+        return true;
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(super.hashCode(), numComponents, componentSize);
+    }
 }

imageio/imageio-tiff/src/test/java/com/twelvemonkeys/imageio/plugins/tiff/ExtraSamplesColorModelTest.java

@@ -40,15 +40,14 @@ import java.awt.color.ColorSpace;
 import java.awt.image.*;
 import java.util.Hashtable;
 
-import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.*;
-import static org.junit.Assert.assertNotNull;
 
 public class ExtraSamplesColorModelTest {
 
     private BufferedImage createExtraSamplesImage(int w, int h, ColorSpace cs, boolean hasAlpha, int extraComponents) {
         int samplesPerPixel = cs.getNumComponents() + (hasAlpha ? 1 : 0) + extraComponents;
 
-        ExtraSamplesColorModel colorModel = new ExtraSamplesColorModel(cs, hasAlpha, true, DataBuffer.TYPE_BYTE, extraComponents);
+        ExtraSamplesColorModel colorModel = createExtraSamplesColorModel(cs, hasAlpha, extraComponents);
         SampleModel sampleModel = new PixelInterleavedSampleModel(DataBuffer.TYPE_BYTE, w, h, samplesPerPixel, samplesPerPixel * w, createOffsets(samplesPerPixel));
 
         WritableRaster raster = Raster.createWritableRaster(sampleModel, new Point(0, 0));
@@ -56,6 +55,10 @@ public class ExtraSamplesColorModelTest {
         return new BufferedImage(colorModel, raster, colorModel.isAlphaPremultiplied(), new Hashtable<>());
     }
 
+    private ExtraSamplesColorModel createExtraSamplesColorModel(ColorSpace cs, boolean hasAlpha, int extraComponents) {
+        return new ExtraSamplesColorModel(cs, hasAlpha, true, DataBuffer.TYPE_BYTE, extraComponents);
+    }
+
     private static int[] createOffsets(int samplesPerPixel) {
         int[] offsets = new int[samplesPerPixel];
         for (int i = 0; i < samplesPerPixel; i++) {
@@ -151,4 +154,19 @@ public class ExtraSamplesColorModelTest {
         assertEquals(Color.BLACK.getRGB(), image.getRGB(0, 0));
         assertEquals(Color.WHITE.getRGB(), image.getRGB(1, 0));
     }
+
+    @Test
+    public void testEquals() {
+        ExtraSamplesColorModel original = createExtraSamplesColorModel(ColorSpaces.getColorSpace(ColorSpace.CS_sRGB), true, 1);
+        ExtraSamplesColorModel equal = createExtraSamplesColorModel(ColorSpaces.getColorSpace(ColorSpace.CS_sRGB), true, 1);
+
+        assertEquals(original, equal);
+        assertEquals(equal, original);
+
+        ExtraSamplesColorModel different = createExtraSamplesColorModel(ColorSpaces.getColorSpace(ColorSpace.CS_sRGB), true, 2);
+        ExtraSamplesColorModel differentToo = createExtraSamplesColorModel(ColorSpaces.getColorSpace(ColorSpace.CS_sRGB), false, 1);
+
+        assertNotEquals(original, different);
+        assertNotEquals(original, differentToo);
+    }
 }