Here you can find the source of copyFile(File in, File out)
public static void copyFile(File in, File out) throws Exception
//package com.java2s; /*/*w w w. jav a 2 s . c o m*/ * Infinitest, a Continuous Test Runner. * * Copyright (C) 2010-2013 * "Ben Rady" <benrady@gmail.com>, * "Rod Coffin" <rfciii@gmail.com>, * "Ryan Breidenbach" <ryan.breidenbach@gmail.com> * "David Gageot" <david@gageot.net>, et al. * * Permission is hereby granted, free of charge, to any person obtaining a copy * of this software and associated documentation files (the "Software"), to deal * in the Software without restriction, including without limitation the rights * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell * copies of the Software, and to permit persons to whom the Software is * furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice shall be included in all * copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE * SOFTWARE. */ import java.io.*; public class Main { public static void copyFile(File in, File out) throws Exception { if (!out.exists()) { out.createNewFile(); } if (!in.exists()) { throw new IllegalArgumentException(in + " does not exist"); } FileInputStream fis = new FileInputStream(in); FileOutputStream fos = new FileOutputStream(out); byte[] buf = new byte[1024]; int i; while ((i = fis.read(buf)) != -1) { fos.write(buf, 0, i); } fis.close(); fos.close(); } }