Java Method Call invoke(Object target, String methodName, Object[] args)

Description

invoke

License

Apache License

Declaration

public static Object invoke(Object target, String methodName, Object[] args) 

Method Source Code

//package com.java2s;
/**/*from  w ww. ja v a  2 s.  c o m*/
 * Copyright 1996-2014 FoxBPM ORG.
 *
 * 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.
 * 
 * @author kenshin
 */

import java.lang.reflect.Method;

public class Main {
    public static Object invoke(Object target, String methodName, Object[] args) {
        try {
            Class<? extends Object> clazz = target.getClass();
            Method method = findMethod(clazz, methodName, args);
            method.setAccessible(true);
            return method.invoke(target, args);
        } catch (Exception e) {
            throw new RuntimeException("couldn't invoke " + methodName + " on " + target, e);
        }
    }

    private static Method findMethod(Class<? extends Object> clazz, String methodName, Object[] args) {
        for (Method method : clazz.getDeclaredMethods()) {
            // TODO add parameter matching
            if (method.getName().equals(methodName) && matches(method.getParameterTypes(), args)) {
                return method;
            }
        }
        Class<?> superClass = clazz.getSuperclass();
        if (superClass != null) {
            return findMethod(superClass, methodName, args);
        }
        return null;
    }

    private static boolean matches(Class<?>[] parameterTypes, Object[] args) {
        if ((parameterTypes == null) || (parameterTypes.length == 0)) {
            return ((args == null) || (args.length == 0));
        }
        if ((args == null) || (parameterTypes.length != args.length)) {
            return false;
        }
        for (int i = 0; i < parameterTypes.length; i++) {
            if ((args[i] != null) && (!parameterTypes[i].isAssignableFrom(args[i].getClass()))) {
                return false;
            }
        }
        return true;
    }
}

Related

1. invoke(Object target, Class clazz, String methodName, Class[] parameterTypes, Object... args)
2. invoke(Object target, Class clazz, String method)
3. invoke(Object target, Method method)
4. invoke(Object target, String methodName)
5. invoke(Object target, String methodName, Object... args)
6. invoke(Object target, String name, Class[] params, Object[] args)
7. invoke(Object targetObject, String method, Class[] paramTypes, Object[] paramValues)
8. invoke(Object targetObject, String methodName, Object... params)
9. invoke(Object thisObject, Method method)