Check for .java for JDK class (close #256)

core/src/main/java/org/easymock/internal/ClassProxyFactory.java

@@ -222,7 +222,8 @@ private <T> ClassLoader classLoader(Class<T> toMock) {
     private static <T> boolean isJdkClassOrWithoutPackage(Class<T> toMock) {
         // null class loader means we are from the bootstrap class loader, the mocks will go in another package in class loader
         // we need to verify for null since some dynamic classes have no package
-        return toMock.getPackage() == null || toMock.getClassLoader() == null;
+        // and I still verify for .java, which isn't perfect but a start, for classes hacked to another class loader like PowerMock does
+        return toMock.getPackage() == null || toMock.getClassLoader() == null || toMock.getName().startsWith("java.");
     }
 
     private ClassLoadingStrategy<ClassLoader> classLoadingStrategy() {

test-integration/src/test/java/org/itests/PowermockTest.java

@@ -23,9 +23,12 @@
 import org.powermock.modules.junit4.PowerMockRunner;
 
 import java.net.URL;
+import java.sql.Timestamp;
 
 import static org.easymock.EasyMock.expect;
+import static org.easymock.EasyMock.mock;
 import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNotNull;
 import static org.junit.Assert.assertNull;
 import static org.junit.Assert.fail;
 import static org.powermock.api.easymock.PowerMock.*;
@@ -75,5 +78,10 @@ public void mockType() {
         assertEquals(getClass(), EasyMockSupport.getMockedClass(mock));
     }
 
+    @Test
+    public void javaSqlPackage() {
+        Timestamp t = mock(Timestamp.class);
+        assertNotNull(t);
+    }
 }