Here you can find the source of concatenate(String separator, T... values)
public static <T> String concatenate(String separator, T... values)
//package com.java2s; /*// ww w . ja v a2 s.c o m * This software code is (c) 2010 T-Mobile USA, Inc. All Rights Reserved. * * Unauthorized redistribution or further use of this material is * prohibited without the express permission of T-Mobile USA, Inc. and * will be prosecuted to the fullest extent of the law. * * Removal or modification of these Terms and Conditions from the source * or binary code of this software is prohibited. In the event that * redistribution of the source or binary code for this software is * approved by T-Mobile USA, Inc., these Terms and Conditions and the * above copyright notice must be reproduced in their entirety and in all * circumstances. * * No name or trademarks of T-Mobile USA, Inc., or of its parent company, * Deutsche Telekom AG or any Deutsche Telekom or T-Mobile entity, may be * used to endorse or promote products derived from this software without * specific prior written permission. * * THIS SOFTWARE IS PROVIDED ON AN "AS IS" AND "WITH ALL FAULTS" BASIS * AND WITHOUT WARRANTIES OF ANY KIND. ALL EXPRESS OR IMPLIED * CONDITIONS, REPRESENTATIONS OR WARRANTIES, INCLUDING ANY IMPLIED * WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR * NON-INFRINGEMENT CONCERNING THIS SOFTWARE, ITS SOURCE OR BINARY CODE * OR ANY DERIVATIVES THEREOF ARE HEREBY EXCLUDED. T-MOBILE USA, INC. * AND ITS LICENSORS SHALL NOT BE LIABLE FOR ANY DAMAGES SUFFERED BY * LICENSEE AS A RESULT OF USING, MODIFYING OR DISTRIBUTING THIS SOFTWARE * OR ITS DERIVATIVES. IN NO EVENT WILL T-MOBILE USA, INC. OR ITS * LICENSORS BE LIABLE FOR LOST REVENUE, PROFIT OR DATA, OR FOR DIRECT, * INDIRECT, SPECIAL, CONSEQUENTIAL, INCIDENTAL OR PUNITIVE DAMAGES, * HOWEVER CAUSED AND REGARDLESS OF THE THEORY OF LIABILITY, ARISING OUT * OF THE USE OF OR INABILITY TO USE THIS SOFTWARE, EVEN IF T-MOBILE USA, * INC. HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. * * THESE TERMS AND CONDITIONS APPLY SOLELY AND EXCLUSIVELY TO THE USE, * MODIFICATION OR DISTRIBUTION OF THIS SOFTWARE, ITS SOURCE OR BINARY * CODE OR ANY DERIVATIVES THEREOF, AND ARE SEPARATE FROM ANY WRITTEN * WARRANTY THAT MAY BE PROVIDED WITH A DEVICE YOU PURCHASE FROM T-MOBILE * USA, INC., AND TO THE EXTENT PERMITTED BY LAW. */ public class Main { public static <T> String concatenate(String separator, T... values) { StringBuilder builder = new StringBuilder(); if (values != null) { for (T value : values) { builder.append(separator).append(value.toString()); } builder.delete(0, separator.length()); } return builder.toString(); } }