Here you can find the source of intersects(Collection
public static <E> boolean intersects(Collection<E> c0, Collection<E> c1)
//package com.java2s; /*//from w w w . j av a 2s . c o m * 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. */ import java.util.Collection; public class Main { /** Returns whether two collections have any elements in common. */ public static <E> boolean intersects(Collection<E> c0, Collection<E> c1) { for (E e : c1) { if (c0.contains(e)) { return true; } } return false; } /** * Returns whether an array of strings contains a given string among the * first <code>length</code> entries. * * @param a Array of strings * @param length Number of entries to search * @param s String to seek * @return Whether array contains the name */ public static boolean contains(String[] a, int length, String s) { for (int i = 0; i < length; i++) { if (a[i].equals(s)) { return true; } } return false; } }