Java Reflection Method Return getMethod(Class clazz, String methodName, Class returnType, Class... inputParams)

Description

get Method

License

Open Source License

Declaration

public static Method getMethod(Class<?> clazz, String methodName, Class<?> returnType,
            Class<?>... inputParams) 

Method Source Code

//package com.java2s;
/*******************************************************************************
 * Copyright (c) 2010 Robert "Unlogic" Olofsson (unlogic@unlogic.se).
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the GNU Lesser Public License v3
 * which accompanies this distribution, and is available at
 * http://www.gnu.org/licenses/lgpl-3.0-standalone.html
 ******************************************************************************/

import java.lang.reflect.Method;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;

public class Main {
    public static Method getMethod(Class<?> clazz, String methodName, Class<?> returnType,
            Class<?>... inputParams) {

        if (inputParams == null) {

            inputParams = new Class<?>[0];
        }/*from  w w w.j a v  a2 s  .  c  o m*/

        Method[] methods = clazz.getDeclaredMethods();

        for (Method method : methods) {

            if (method.getName().equals(methodName) && returnType.isAssignableFrom(method.getReturnType())
                    && Arrays.equals(inputParams, method.getParameterTypes())) {

                return method;
            }
        }

        return null;
    }

    public static Method getMethod(Class<?> clazz, String methodName, int argumentCount) {

        List<Method> methods = getMethods(clazz);

        for (Method method : methods) {

            if (!method.getName().equalsIgnoreCase(methodName)) {

                continue;
            }

            if (method.getParameterTypes().length != argumentCount) {

                continue;
            }

            return method;
        }

        return null;
    }

    public static List<Method> getMethods(Class<?> clazz) {

        ArrayList<Method> methods = new ArrayList<Method>();

        methods.addAll(Arrays.asList(clazz.getDeclaredMethods()));

        clazz = clazz.getSuperclass();

        while (clazz != Object.class) {

            methods.addAll(Arrays.asList(clazz.getDeclaredMethods()));

            clazz = clazz.getSuperclass();
        }

        return methods;
    }
}

Related

1. getMethod(Class clazz, String name, String returnType, String[] args)
2. getMethod(Class parentClass, Class returnType, String methodName, Class... types)
3. getMethod(Class type, String name, Class returnType, Class paramType, boolean caseSensitive)
4. getMethodByReturnType(final Class source, final Class type)