Support byte[] in JaxbMarshaller under JDK 7

JDK7 changed its reflections API in order to resolve
http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=5041784

In short, JDK 5 and 6 (wrongly) return GenericArrayTypes in certain
reflection scenarios, whereas JDK 7 changed this to return a normal
array type. For Jaxb2Marshaller, this meant that marshaling byte arrays
was not supported under JDK 7.

This change fixes that, so that Jaxb2Marhsaller supports marshalling
byte arrays again (under JDK 5, 6 or 7).

Author: poutsma

spring-oxm/src/main/java/org/springframework/oxm/jaxb/Jaxb2Marshaller.java

@@ -16,7 +16,7 @@
 
 package org.springframework.oxm.jaxb;
 
-import java.awt.*;
+import java.awt.Image;
 import java.io.ByteArrayInputStream;
 import java.io.IOException;
 import java.io.InputStream;
@@ -76,6 +76,7 @@
 import org.springframework.beans.factory.BeanClassLoaderAware;
 import org.springframework.beans.factory.InitializingBean;
 import org.springframework.context.ResourceLoaderAware;
+import org.springframework.core.JdkVersion;
 import org.springframework.core.annotation.AnnotationUtils;
 import org.springframework.core.io.Resource;
 import org.springframework.core.io.ResourceLoader;
@@ -502,10 +503,17 @@ public boolean supports(Type genericType) {
 				Type typeArgument = parameterizedType.getActualTypeArguments()[0];
 				if (typeArgument instanceof Class) {
 					Class<?> classArgument = (Class<?>) typeArgument;
-					return (isPrimitiveWrapper(classArgument) || isStandardClass(classArgument) ||
-							supportsInternal(classArgument, false));
+					if (JdkVersion.getMajorJavaVersion() >= JdkVersion.JAVA_17 && classArgument.isArray()) {
+						return classArgument.getComponentType().equals(Byte.TYPE);
+					}
+					else {
+						return (isPrimitiveWrapper(classArgument) || isStandardClass(classArgument) ||
+								supportsInternal(classArgument, false));
+					}
 				}
-				else if (typeArgument instanceof GenericArrayType) {
+				else if (JdkVersion.getMajorJavaVersion() <= JdkVersion.JAVA_16 &&
+						typeArgument instanceof GenericArrayType) {
+					// see http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=5041784
 					GenericArrayType arrayType = (GenericArrayType) typeArgument;
 					return arrayType.getGenericComponentType().equals(Byte.TYPE);
 				}
@@ -867,13 +875,13 @@ public boolean isXOPPackage() {
 	 */
 	private static class ByteArrayDataSource implements DataSource {
 
-		private byte[] data;
+		private final byte[] data;
 
-		private String contentType;
+		private final String contentType;
 
-		private int offset;
+		private final int offset;
 
-		private int length;
+		private final int length;
 
 		private ByteArrayDataSource(String contentType, byte[] data, int offset, int length) {
 			this.contentType = contentType;