Java Reflection Method Invoke invokeMethod(Object target, Class clazz, String methodName, Class[] types, Object[] args)

Description

Invoke method.

License

Open Source License

Parameter

Parameter	Description
target	the target
clazz	the class
methodName	the method name
types	the types
args	the args

Return

method's return value

Declaration

private static Object invokeMethod(Object target, Class<?> clazz, String methodName, Class[] types,
        Object[] args) 

Method Source Code

//package com.java2s;
/*/*from   ww  w  .j av a  2s  . c o  m*/
 * JBoss, Home of Professional Open Source.
 * Copyright 2011, Red Hat, Inc., and individual contributors
 * as indicated by the @author tags. See the copyright.txt file in the
 * distribution for a full listing of individual contributors.
 *
 * This is free software; you can redistribute it and/or modify it
 * under the terms of the GNU Lesser General Public License as
 * published by the Free Software Foundation; either version 2.1 of
 * the License, or (at your option) any later version.
 *
 * This software is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this software; if not, write to the Free
 * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA, or see the FSF site: http://www.fsf.org.
 */

import java.lang.reflect.Method;

public class Main {
    /**
     * Invoke method.
     *
     * @param target     the target
     * @param clazz      the class
     * @param methodName the method name
     * @param types      the types
     * @param args       the args
     * @return method's return value
     */
    private static Object invokeMethod(Object target, Class<?> clazz, String methodName, Class[] types,
            Object[] args) {
        final Method m = findMethod(clazz, methodName, types);
        try {
            return m.invoke(target, args);
        } catch (Exception e) {
            throw new RuntimeException(e);
        }
    }

    /**
     * Find method.
     *
     * @param clazz      the class
     * @param methodName the method name
     * @param types      the types
     * @return method's return value
     */
    private static Method findMethod(Class<?> clazz, String methodName, Class[] types) {
        if (clazz == null)
            throw new IllegalArgumentException("Null class");
        if (methodName == null)
            throw new IllegalArgumentException("Null method name");

        try {
            Class<?> current = clazz;
            while (current != null) {
                try {
                    final Method m = current.getDeclaredMethod(methodName, types);
                    m.setAccessible(true);
                    return m;
                } catch (NoSuchMethodException ignored) {
                }
                current = current.getSuperclass();
            }
        } catch (Throwable t) {
            throw new RuntimeException(t);
        }
        throw new IllegalStateException("Couldn't find method: " + clazz.getName() + " / " + methodName);
    }
}

Related

1. invokeMethod(Object owner, String methodName)
2. invokeMethod(Object owner, String methodName, Object[] args)
3. invokeMethod(Object parent, String method, Class[] paramTypes, Object[] args)
4. invokeMethod(Object source, String method, Collection