package test;
 import java.io.BufferedInputStream;
 import java.io.BufferedOutputStream;
 import java.io.File;
 import java.io.FileInputStream;
 import java.io.FileOutputStream;
 import java.io.IOException;
 import java.io.InputStream;
 import java.nio.channels.FileChannel;

 public class Test {
public static void main(String[] args) {
File source = new File("E:\\tools\\fmw_12.1.3.0.0_wls.jar");
File target = new File("E:\\tools\\fmw_12.1.3.0.0_wls-copy.jar");
long start, end;

start = System.currentTimeMillis();
fileChannelCopy(source, target);
end = System.currentTimeMillis();
System.out.println("文件通道用時：" + (end - start) + "毫秒");

start = System.currentTimeMillis();
copy(source, target);
end = System.currentTimeMillis();
System.out.println("普通緩沖用時：" + (end - start) + "毫秒");
}

/**
 * 使用文件通道的方式復制文件
 * @param source 源文件
 * @param target 目標文件
 */
 public static void fileChannelCopy(File source, File target) {


  FileInputStream in = null;
  FileOutputStream out = null;
  FileChannel inChannel = null;
  FileChannel outChannel = null;
  try {
  in = new FileInputStream(source);
  out = new FileOutputStream(target);
  inChannel = in.getChannel();//得到對應的文件通道
  outChannel = out.getChannel();//得到對應的文件通道
  inChannel.transferTo(0, inChannel.size(), outChannel);//連接兩個通道，并且從inChannel通道讀取，然后寫入outChannel通道
 } catch (IOException e) {
  e.printStackTrace();
  } finally {
  try {
   in.close();
   inChannel.close();
   out.close();
   outChannel.close();
  } catch (IOException e) {
   e.printStackTrace();
  }


  }


 }
 
/**
* 普通緩沖復制
* @param source 源文件
* @param target 目標文件
*/
public static void copy (File source, File target) {
InputStream in = null;
BufferedOutputStream out = null;
try {
in = new BufferedInputStream(new FileInputStream(source));
out = new BufferedOutputStream(new FileOutputStream(target));
byte[] buf = new byte[4096];
int i;
while ((i = in.read(buf)) != -1) {
out.write(buf, 0, i);
}
} catch (Exception e) {
e.printStackTrace();
} finally {
try {
if (null != in) {
in.close();
}
if (null != out) {
out.close();
}
} catch (IOException e) {
e.printStackTrace();
}
}
}
 }

 }