Here you can find the source of copyFile(File source, File dest)
public static void copyFile(File source, File dest) throws IOException
//package com.java2s; /*// w w w . j a v a2 s. co m * Copyright (c) 2012 EDC * * This file is part of Stepping Stone. * * Stepping Stone is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation, either version 3 of the License, or * (at your option) any later version. * * Stepping Stone is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with Stepping Stone. If not, see <http://www.gnu.org/licenses/gpl.txt>. */ import java.io.File; import java.io.FileInputStream; import java.io.FileOutputStream; import java.io.IOException; import java.io.InputStream; import java.io.OutputStream; import java.io.Reader; import java.util.zip.ZipFile; public class Main { public static void copyFile(File source, File dest) throws IOException { copyStream(new FileInputStream(source), new FileOutputStream(dest)); } /** * Copy all bytes from in to out. Flush out at the end but do not close the streams. * * @param in * @param out * @throws IOException */ public static int copyStream(InputStream in, OutputStream out, boolean closeIn, boolean closeOut) throws IOException { int totalBytes = 0; try { byte[] buff = new byte[1024 * 4]; int bytesRead = 0; while ((bytesRead = in.read(buff)) != -1) { if (bytesRead > 0) { out.write(buff, 0, bytesRead); totalBytes += bytesRead; } } out.flush(); } finally { if (closeIn) closeGracefully(in); if (closeOut) closeGracefully(out); } return totalBytes; } public static int copyStream(InputStream in, OutputStream out) throws IOException { return copyStream(in, out, true, true); } public static void closeGracefully(InputStream is) { if (is != null) { try { is.close(); } catch (IOException ignore) { } } } public static void closeGracefully(Reader r) { if (r != null) { try { r.close(); } catch (IOException ignore) { } } } public static void closeGracefully(OutputStream out) { if (out != null) { try { out.close(); } catch (IOException ignore) { } } } public static void closeGracefully(ZipFile zipFile) { if (zipFile != null) { try { zipFile.close(); } catch (IOException ignore) { } } } }