Here you can find the source of isCollectionType(final Class> cls)
public static boolean isCollectionType(final Class<?> cls)
//package com.java2s; /*/*from ww w.ja v a2s . c om*/ * 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. */ public class Main { public static boolean isCollectionType(final Class<?> cls) { return java.util.Collection.class.isAssignableFrom(cls); } }