Spring Framework example source code file (ResourceOverridingShadowingClassLoaderTests.java)

This example Spring Framework source code file (ResourceOverridingShadowingClassLoaderTests.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - Spring Framework tags/keywords

classloader, existing_resource, existing_resource, io, ioexception, ioexception, resourceoverridingshadowingclassloader, resourceoverridingshadowingclassloader, resourceoverridingshadowingclassloadertests, resourceoverridingshadowingclassloadertests, string, testcase, util

The Spring Framework ResourceOverridingShadowingClassLoaderTests.java source code

/*
 * Copyright 2002-2006 the original author or authors.
 * 
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * 
 *      http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.springframework.instrument.classloading;

import java.io.IOException;
import java.util.Enumeration;

import junit.framework.TestCase;

/**
 * @author Rod Johnson
 * @since 2.0
 */
public class ResourceOverridingShadowingClassLoaderTests extends TestCase {
	
	private static final String EXISTING_RESOURCE = "org/springframework/instrument/classloading/testResource.xml";
	
	private ClassLoader thisClassLoader = getClass().getClassLoader();
	
	private ResourceOverridingShadowingClassLoader overridingLoader = new ResourceOverridingShadowingClassLoader(thisClassLoader);
	
	
	public void testFindsExistingResourceWithGetResourceAndNoOverrides() {
		assertNotNull(thisClassLoader.getResource(EXISTING_RESOURCE));
		assertNotNull(overridingLoader.getResource(EXISTING_RESOURCE));
	}
	
	public void testDoesNotFindExistingResourceWithGetResourceAndNullOverride() {
		assertNotNull(thisClassLoader.getResource(EXISTING_RESOURCE));
		overridingLoader.override(EXISTING_RESOURCE, null);
		assertNull(overridingLoader.getResource(EXISTING_RESOURCE));
	}
	
	public void testFindsExistingResourceWithGetResourceAsStreamAndNoOverrides() {
		assertNotNull(thisClassLoader.getResourceAsStream(EXISTING_RESOURCE));
		assertNotNull(overridingLoader.getResourceAsStream(EXISTING_RESOURCE));
	}
	
	public void testDoesNotFindExistingResourceWithGetResourceAsStreamAndNullOverride() {
		assertNotNull(thisClassLoader.getResourceAsStream(EXISTING_RESOURCE));
		overridingLoader.override(EXISTING_RESOURCE, null);
		assertNull(overridingLoader.getResourceAsStream(EXISTING_RESOURCE));
	}
	
	public void testFindsExistingResourceWithGetResourcesAndNoOverrides() throws IOException {
		assertNotNull(thisClassLoader.getResources(EXISTING_RESOURCE));
		assertNotNull(overridingLoader.getResources(EXISTING_RESOURCE));
		assertEquals(1, countElements(overridingLoader.getResources(EXISTING_RESOURCE)));
	}
	
	public void testDoesNotFindExistingResourceWithGetResourcesAndNullOverride() throws IOException {
		assertNotNull(thisClassLoader.getResources(EXISTING_RESOURCE));
		overridingLoader.override(EXISTING_RESOURCE, null);
		assertEquals(0, countElements(overridingLoader.getResources(EXISTING_RESOURCE)));
	}

	private int countElements(Enumeration e) {
		int elts = 0;
		while (e.hasMoreElements()) {
			e.nextElement();
			++elts;
		}
		return elts;
	}
}