/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You 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.apache.cocoon.util;
import java.io.File;
import java.io.IOException;
import java.net.MalformedURLException;
import java.net.URL;
/**
* A collection of class management utility methods.
*
* @author <a href="mailto:ricardo@apache.org">Ricardo Rocha</a>
* @author <a href="mailto:stefano@apache.org">Stefano Mazzocchi</a>
* @version CVS $Id: ClassUtils.java 433543 2006-08-22 06:22:54Z crossley $
*/
public class ClassUtils {
/**
* Create a new instance given a class name
*
* @param className A class name
* @return A new instance
* @exception Exception If an instantiation error occurs
*/
public static Object newInstance(String className) throws Exception {
return ClassUtils.loadClass(className).newInstance();
}
/**
* Load a class given its name.
* BL: We wan't to use a known ClassLoader--hopefully the hierarchy
* is set correctly.
*
* @param className A class name
* @return The class pointed to by <code>className</code>
* @exception ClassNotFoundException If a loading error occurs
*/
public static Class loadClass(String className) throws ClassNotFoundException {
return ClassUtils.getClassLoader().loadClass(className);
}
/**
* Return a resource URL.
* BL: if this is command line operation, the classloading issues
* are more sane. During servlet execution, we explicitly set
* the ClassLoader.
*
* @return The context classloader.
* @exception MalformedURLException If a loading error occurs
*/
public static URL getResource(String resource) throws MalformedURLException {
return ClassUtils.getClassLoader().getResource(resource);
}
/**
* Return the context classloader.
* BL: if this is command line operation, the classloading issues
* are more sane. During servlet execution, we explicitly set
* the ClassLoader.
*
* @return The context classloader.
*/
public static ClassLoader getClassLoader() {
return Thread.currentThread().getContextClassLoader();
}
/**
* Tests if a class implements a given interface
*
* @return true if class implements given interface.
* @deprecated Will be removed 2 versions after 2.1.5
*/
public static boolean implementsInterface(String className, String iface) throws Exception {
Class class1 = ClassUtils.loadClass (className);
Class class2 = ClassUtils.loadClass (iface);
return ClassUtils.implementsInterface(class1, class2);
}
/**
* Tests if a class implements a given interface
*
* @return true if class implements given interface.
* @deprecated Will be removed 2 versions after 2.1.5
*/
public static boolean implementsInterface(Class class1, Class iface) {
return iface.isAssignableFrom (class1);
}
/**
* Determine the last modification date for this
* class file or its enclosing library
*
* @param aClass A class whose last modification date is queried
* @return The time the given class was last modified
* @exception IOException IOError
* @exception IllegalArgumentException The class was not loaded from a file
* or directory
* @deprecated Will be removed 2 versions after 2.1.5
*/
public static long lastModified(Class aClass)
throws IOException, IllegalArgumentException {
URL url = aClass.getProtectionDomain().getCodeSource().getLocation();
if (!url.getProtocol().equals("file")) {
throw new IllegalArgumentException("Class was not loaded from a file url");
}
File directory = new File(url.getFile());
if (!directory.isDirectory()) {
throw new IllegalArgumentException("Class was not loaded from a directory");
}
String className = aClass.getName();
String basename = className.substring(className.lastIndexOf(".") + 1);
File file = new File(directory, basename + ".class");
return file.lastModified();
}
/**
* Gets the absolute pathname of the class file
* containing the specified class name, as prescribed
* by the current classpath.
*
* @param aClass Name of the class.
* @deprecated Will be removed 2 versions after 2.1.5
*/
public static String which(Class aClass) {
String path = null;
try {
path = aClass.getProtectionDomain().getCodeSource().getLocation().toString();
} catch (Throwable t){
}
return path;
}
}
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