/* Copyright 2004, 2005, 2006 Acegi Technology Pty Limited
*
* 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.security.util;
import java.lang.reflect.Method;
import org.aopalliance.intercept.MethodInvocation;
import org.springframework.aop.framework.Advised;
import org.springframework.aop.support.AopUtils;
import org.springframework.util.Assert;
/**
* Static utility methods for creating <code>MethodInvocation</code>s usable within Spring Security.
* <p>
* All methods of this class return a {@link org.springframework.security.util.SimpleMethodInvocation}.
*
* @author Ben Alex
*/
public final class MethodInvocationUtils {
//~ Methods ========================================================================================================
/**
* Generates a <code>MethodInvocation</code> for specified <code>methodName</code> on the passed object,
* using the <code>args</code> to locate the method.
*
* @param object the object that will be used to find the relevant <code>Method</code>
* @param methodName the name of the method to find
* @param args arguments that are required as part of the method signature (can be empty)
*
* @return a <code>MethodInvocation</code>, or <code>null</code> if there was a problem
*/
public static MethodInvocation create(Object object, String methodName, Object... args) {
Assert.notNull(object, "Object required");
Class<?>[] classArgs = null;
if (args != null) {
classArgs = new Class<?>[args.length];
for (int i = 0; i < args.length; i++) {
classArgs[i] = args[i].getClass();
}
}
// Determine the type that declares the requested method, taking into account proxies
Class<?> target = AopUtils.getTargetClass(object);
if (object instanceof Advised) {
Advised a = (Advised) object;
if (!a.isProxyTargetClass()) {
Class<?>[] possibleInterfaces = a.getProxiedInterfaces();
for (Class<?> possibleInterface : possibleInterfaces) {
try {
possibleInterface.getMethod(methodName, classArgs);
// to get here means no exception happened
target = possibleInterface;
break;
} catch (Exception ignored) {
// try the next one
}
}
}
}
return createFromClass(object, target, methodName, classArgs, args);
}
/**
* Generates a <code>MethodInvocation</code> for the specified <code>methodName</code> on the passed class.
*
* If a method with this name, taking no arguments does not exist, it will check through the declared
* methods on the class, until one is found matching the supplied name. If more than one method name matches,
* an <tt>IllegalArgumentException</tt> will be raised.
*
* @param clazz the class of object that will be used to find the relevant <code>Method</code>
* @param methodName the name of the method to find
*
* @return a <code>MethodInvocation</code>, or <code>null</code> if there was a problem
*/
public static MethodInvocation createFromClass(Class<?> clazz, String methodName) {
MethodInvocation mi = createFromClass(null, clazz, methodName, null, null);
if (mi == null) {
for (Method m : clazz.getDeclaredMethods()) {
if (m.getName().equals(methodName)) {
if (mi != null) {
throw new IllegalArgumentException("The class " + clazz + " has more than one method named" +
" '" + methodName + "'");
}
mi = new SimpleMethodInvocation(null, m);
}
}
}
return mi;
}
/**
* Generates a <code>MethodInvocation</code> for specified <code>methodName</code> on the passed class,
* using the <code>args</code> to locate the method.
*
* @param targetObject the object being invoked
* @param clazz the class of object that will be used to find the relevant <code>Method</code>
* @param methodName the name of the method to find
* @param classArgs arguments that are required to locate the relevant method signature
* @param args the actual arguments that should be passed to SimpleMethodInvocation
* @return a <code>MethodInvocation</code>, or <code>null</code> if there was a problem
*/
public static MethodInvocation createFromClass(Object targetObject, Class<?> clazz, String methodName,
Class<?>[] classArgs, Object[] args) {
Assert.notNull(clazz, "Class required");
Assert.hasText(methodName, "MethodName required");
Method method;
try {
method = clazz.getMethod(methodName, classArgs);
} catch (NoSuchMethodException e) {
return null;
}
return new SimpleMethodInvocation(targetObject, method, args);
}
}