Skip ImageTest if JPEG codec from com/sun/image/codec isn't available in the Java runtime.

OpenJDK even in Java 8 (update 222) doesn't include these codecs. Oracle JDK has it in
Java 8, but not in subsequent Java releases.

src/etc/testcases/taskdefs/optional/image/image.xml

@@ -23,47 +23,48 @@
   <target name="setUp">
     <mkdir dir="${output}"/>
     <property name="src.dir" location="${basedir}/src"/>
+    <available classname="com.sun.image.codec.jpeg.JPEGCodec" property="jpeg.codec.available"/>
   </target>
 
   <target name="main" depends="testSimpleScale">
   </target>
 
   <!-- this should produce a single file in the dest dir -->
-  <target name="testSimpleScale" depends="setUp">
+  <target name="testSimpleScale" depends="setUp" if="jpeg.codec.available">
     <image includes="*.jpg" srcdir="${src.dir}" destdir="${output}" overwrite="no" failonerror="no">
       <scale width="300" proportions="width"/>
     </image>
   </target>
 
   <!-- this should put some text in the log -->
-  <target name="testEchoToLog" depends="setUp">
+  <target name="testEchoToLog" depends="setUp" if="jpeg.codec.available">
     <image includes="*.jpg" srcdir="${src.dir}" destdir="${output}" overwrite="no" failonerror="no">
       <scale width="300" proportions="width"/>
     </image>
   </target>
 
   <!-- this should produce a single file in the dest dir -->
-  <target name="testFailOnError" depends="setUp">
+  <target name="testFailOnError" depends="setUp" if="jpeg.codec.available">
     <image includes="*.jpg" srcdir="${src.dir}" destdir="${output}" overwrite="no" failonerror="yes">
       <scale width="300" proportions="width"/>
     </image>
   </target>
 
   <!-- this should produce a single file in the dest dir, overwriting any existing file -->
-  <target name="testOverwriteTrue" depends="setUp">
+  <target name="testOverwriteTrue" depends="setUp" if="jpeg.codec.available">
     <image includes="*.jpg" srcdir="${src.dir}" destdir="${output}" overwrite="true" failonerror="no">
       <scale width="300" proportions="width"/>
     </image>
   </target>
 
   <!-- this should not overwrite the existing file -->
-  <target name="testOverwriteFalse" depends="setUp">
+  <target name="testOverwriteFalse" depends="setUp" if="jpeg.codec.available">
     <image includes="*.jpg" srcdir="${src.dir}" destdir="${output}" overwrite="false" failonerror="no">
       <scale width="300" proportions="width"/>
     </image>
   </target>
 
-  <target name="testSimpleScaleWithMapper" depends="setUp">
+  <target name="testSimpleScaleWithMapper" depends="setUp" if="jpeg.codec.available">
     <image includes="*.jpg" srcdir="${src.dir}"
            destdir="${output}" overwrite="no" failonerror="no">
       <scale width="300" proportions="width"/>

src/tests/junit/org/apache/tools/ant/taskdefs/optional/image/ImageTest.java

@@ -34,6 +34,7 @@ import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertThat;
 import static org.junit.Assert.assertTrue;
 import static org.junit.Assume.assumeFalse;
+import static org.junit.Assume.assumeNotNull;
 import static org.junit.Assume.assumeTrue;
 
 /**
@@ -63,14 +64,17 @@ public class ImageTest {
     @Test
     public void testEchoToLog() {
         buildRule.executeTarget("testEchoToLog");
+        assumeNotNull("JPEG codec is unavailable in classpath",
+                buildRule.getProject().getProperty("jpeg.codec.available"));
         assertThat(buildRule.getLog(), containsString("Processing File"));
     }
 
     @Test
     public void testSimpleScale() {
         buildRule.executeTarget("testSimpleScale");
+        assumeNotNull("JPEG codec is unavailable in classpath",
+                buildRule.getProject().getProperty("jpeg.codec.available"));
         assertThat(buildRule.getLog(), containsString("Processing File"));
-
         File f = new File(buildRule.getOutputDir(), LARGEIMAGE);
         assertTrue("Did not create " + f.getAbsolutePath(), f.exists());
     }
@@ -78,6 +82,8 @@ public class ImageTest {
     @Test
     public void testOverwriteTrue() {
         buildRule.executeTarget("testSimpleScale");
+        assumeNotNull("JPEG codec is unavailable in classpath",
+                buildRule.getProject().getProperty("jpeg.codec.available"));
         assertThat(buildRule.getLog(), containsString("Processing File"));
         File f = new File(buildRule.getOutputDir(), LARGEIMAGE);
         assumeTrue("Could not change file modification date",
@@ -93,6 +99,8 @@ public class ImageTest {
     @Test
     public void testOverwriteFalse() {
         buildRule.executeTarget("testSimpleScale");
+        assumeNotNull("JPEG codec is unavailable in classpath",
+                buildRule.getProject().getProperty("jpeg.codec.available"));
         assertThat(buildRule.getLog(), containsString("Processing File"));
         File f = new File(buildRule.getOutputDir(), LARGEIMAGE);
         long lastModified = f.lastModified();
@@ -106,6 +114,8 @@ public class ImageTest {
     @Test
     public void testSimpleScaleWithMapper() {
         buildRule.executeTarget("testSimpleScaleWithMapper");
+        assumeNotNull("JPEG codec is unavailable in classpath",
+                buildRule.getProject().getProperty("jpeg.codec.available"));
         assertThat(buildRule.getLog(), containsString("Processing File"));
         File f = new File(buildRule.getOutputDir(), "scaled-" + LARGEIMAGE);
         assertTrue("Did not create " + f.getAbsolutePath(), f.exists());