Here you can find the source of copyFile(File sourceFile, File destFile)
public static void copyFile(File sourceFile, File destFile) throws IOException
//package com.java2s; import java.io.File; import java.io.FileInputStream; import java.io.FileOutputStream; import java.io.IOException; import java.nio.channels.FileChannel; public class Main { /** Copies a file */ public static void copyFile(File sourceFile, File destFile) throws IOException { FileChannel source = null; FileChannel destination = null; try {// w w w.j a v a2 s . c o m source = new FileInputStream(sourceFile).getChannel(); destination = new FileOutputStream(destFile).getChannel(); destination.transferFrom(source, 0, source.size()); } finally { if (source != null) { source.close(); } if (destination != null) { destination.close(); } } } }