support JPMS classloading

clean up

Author: kwin

src/main/java/org/codehaus/plexus/classworlds/ClassWorld.java

@@ -74,10 +74,10 @@ public ClassRealm newRealm( String id, ClassLoader classLoader )
 
     /**
      * Shortcut for {@link #newRealm(String, ClassLoader, Set)} with the class loader of the current class.
-     * @param id
-     * @param allowedResourceNamePrefixes
+     * @param id The identifier for this realm, must not be <code>null</code>.
+     * @param allowedResourceNamePrefixes the prefixes of resource names which should be exposed. Separator '/' is used here (even for classes).
      * @return the created class realm
-     * @throws DuplicateRealmException
+     * @throws DuplicateRealmException in case a realm with the given id does already exist
      * @since 2.7.0
      * @see FilteredClassRealm
      */
@@ -90,11 +90,12 @@ public synchronized ClassRealm newRealm( String id, Set<String> allowedResourceN
     /**
      * Adds a class realm with filtering.
      * Only resources/classes starting with one of the given prefixes are exposed.
-     * @param id
-     * @param classLoader
+     * @param id The identifier for this realm, must not be <code>null</code>.
+     * @param baseClassLoader The base class loader for this realm, may be <code>null</code> to use the bootstrap class
+     *            loader.
      * @param allowedResourceNamePrefixes the prefixes of resource names which should be exposed. Separator '/' is used here (even for classes).
      * @return the created class realm
-     * @throws DuplicateRealmException
+     * @throws DuplicateRealmException in case a realm with the given id does already exist
      * @since 2.7.0
      * @see FilteredClassRealm
      */

src/main/java/org/codehaus/plexus/classworlds/realm/ClassRealm.java

@@ -272,7 +272,8 @@ private Class<?> unsynchronizedLoadClass( String name, boolean resolve )
         }
     }
 
-    // java11
+    // overwrites https://docs.oracle.com/en/java/javase/11/docs/api/java.base/java/lang/ClassLoader.html#findClass(java.lang.String,java.lang.String) 
+    // introduced in Java9
     protected Class<?> findClass( String moduleName, String name )
     {
         if ( moduleName != null )
@@ -281,7 +282,7 @@ protected Class<?> findClass( String moduleName, String name )
         }
         try
         {
-            return super.findClass( name );
+            return findClassInternal( name );
         }
         catch ( ClassNotFoundException e )
         {

src/main/java/org/codehaus/plexus/classworlds/realm/FilteredClassRealm.java

@@ -1,5 +1,3 @@
-package org.codehaus.plexus.classworlds.realm;
-
 /*
  * Licensed to the Apache Software Foundation (ASF) under one
  * or more contributor license agreements.  See the NOTICE file
@@ -18,6 +16,7 @@
  * specific language governing permissions and limitations
  * under the License.
  */
+package org.codehaus.plexus.classworlds.realm;
 
 import java.io.IOException;
 import java.net.URL;

src/test/java/org/codehaus/plexus/classworlds/realm/ClassRealmImplTest.java

@@ -443,7 +443,7 @@ public void testLoadClass_ClassWorldsClassRepeatedly()
     }
 
     @Test
-    public void testLoadClass_Java11()
+    public void testLoadClassWithModuleName_Java9()
     {
         final ExtendedClassRealm mainRealm = new ExtendedClassRealm( world );
         mainRealm.addURL( getJarUrl( "a.jar" ) );
@@ -503,13 +503,17 @@ public void testGetResources_SelfBeforeParent()
         assertEquals( Arrays.asList( childUrl, parentUrl ), urls );
     }
 
-    // simulate new loadClass(Module,String) from java11
-    // it is reversed in terms of inheritance but enables to simulate the same behavior in these tests
+    /**
+     * Simulates new {@code java.lang.ClassLoader#findClass(String,String)} introduced with Java 9.
+     * It is reversed in terms of inheritance but enables to simulate the same behavior in these tests.
+     * @see <a href="https://docs.oracle.com/en/java/javase/11/docs/api/java.base/java/lang/ClassLoader.html#findClass(java.lang.String,java.lang.String)">ClassLoader#findClass(String,String)</a>
+     */
     private static class ExtendedClassRealm extends ClassRealm
     {
+        
         public ExtendedClassRealm(final ClassWorld world)
         {
-            super( world, "java11", Thread.currentThread().getContextClassLoader() );
+            super( world, "java9", Thread.currentThread().getContextClassLoader() );
         }
 
         public Class<?> simulateLoadClassFromModule(final String name)

src/test/java/org/codehaus/plexus/classworlds/realm/FilteredClassRealmTest.java

@@ -1,5 +1,3 @@
-package org.codehaus.plexus.classworlds.realm;
-
 /*
  * Licensed to the Apache Software Foundation (ASF) under one
  * or more contributor license agreements.  See the NOTICE file
@@ -18,7 +16,10 @@
  * specific language governing permissions and limitations
  * under the License.
  */
+package org.codehaus.plexus.classworlds.realm;
 
+import java.io.IOException;
+import java.util.Collections;
 import java.util.HashSet;
 import java.util.Set;
 
@@ -36,34 +37,78 @@
 public class FilteredClassRealmTest extends AbstractClassWorldsTestCase
 {
     private ClassWorld world;
+    private ClassRealm realmA;
 
     @Before
-    public void setUp()
+    public void setUp() throws DuplicateRealmException
     {
         this.world = new ClassWorld();
+        // only allow loading resources whose names start with "a."
+        Set<String> allowedResourcePrefixes = new HashSet<>();
+        allowedResourcePrefixes.add( "a." );
+        allowedResourcePrefixes.add( "a/Aa" );
+        realmA = this.world.newRealm( "realmA",  allowedResourcePrefixes );
     }
 
     @Test
-    public void testLoadClassAndResourcesFiltered()
+    public void testLoadResources()
         throws Exception
     {
-        // only allow loading resources whose names start with "a."
-        Set<String> allowedResourcePrefixes = new HashSet<>();
-        allowedResourcePrefixes.add( "a." );
-        allowedResourcePrefixes.add( "a/Aa" );
-        ClassRealm realmA = this.world.newRealm( "realmA",  allowedResourcePrefixes );
+        realmA.addURL( getJarUrl( "a.jar" ) );
+        assertNull( realmA.getResource( "common.properties" ) );
+        assertFalse( realmA.getResources( "common.properties" ).hasMoreElements() );
+        
+        assertNotNull( realmA.getResource( "a.properties" ) );
+        assertTrue( realmA.getResources( "a.properties" ).hasMoreElements() );
+    }
 
+    @Test
+    public void testLoadClass() throws ClassNotFoundException
+    {
         assertThrows( ClassNotFoundException.class, () -> realmA.loadClass( "a.Aa" ) );
         realmA.addURL( getJarUrl( "a.jar" ) );
 
         assertNotNull( realmA.loadClass( "a.Aa" ) );
         assertThrows( ClassNotFoundException.class, () -> realmA.loadClass( "a.A" ) );
 
-        assertNull( realmA.getResource( "common.properties" ) );
-        assertFalse( realmA.getResources( "common.properties" ).hasMoreElements() );
-        
-        assertNotNull( realmA.getResource( "a.properties" ) );
-        assertTrue( realmA.getResources( "a.properties" ).hasMoreElements() );
+        assertNotNull( realmA.loadClass(  "a.Aa" ) );
+        assertThrows( ClassNotFoundException.class, () -> realmA.loadClass( "a.A" ) );
     }
 
+    @Test
+    public void testLoadClassWithModule() throws IOException
+    {
+        try (ExtendedFilteredClassRealm realmA = new ExtendedFilteredClassRealm( world, Collections.singleton( "a/Aa" ) )) {
+            realmA.addURL( getJarUrl( "a.jar" ) );
+            assertNotNull( realmA.simulateLoadClassFromModule( "a.Aa" ) );
+            assertNull( realmA.simulateLoadClassFromModule( "a.A" ) );
+        }
+    }
+
+    /**
+     * Simulates new {@code java.lang.ClassLoader#findClass(String,String)} introduced with Java 9.
+     * It is reversed in terms of inheritance but enables to simulate the same behavior in these tests.
+     * @see <a href="https://docs.oracle.com/en/java/javase/11/docs/api/java.base/java/lang/ClassLoader.html#findClass(java.lang.String,java.lang.String)">ClassLoader#findClass(String,String)</a>
+     * @see ClassRealmImplTest.ExtendedClassRealm
+     */
+    static class ExtendedFilteredClassRealm extends FilteredClassRealm
+    {
+
+        public ExtendedFilteredClassRealm( final ClassWorld world, Set<String> allowedResourcePrefixes )
+        {
+            super( allowedResourcePrefixes, world, "java9", Thread.currentThread().getContextClassLoader() );
+        }
+
+        public Class<?> simulateLoadClassFromModule(final String name)
+        {
+            synchronized (getClassLoadingLock(name))
+            {
+                Class<?> c = findLoadedClass(name);
+                if (c == null) {
+                    c = findClass(null, name);
+                }
+                return c;
+            }
+        }
+    }
 }