使用Channel进行本地文件读写的简单实例2

Posted 2020-12-19 mc-74120

使用一个缓冲区进行读写操作：

 public static void main(String[] args) throws IOException {
        FileInputStream fileInputStream = new FileInputStream("1.txt");
        FileChannel channel01 = fileInputStream.getChannel();

        FileOutputStream fileOutputStream=new FileOutputStream("2.txt");
        FileChannel channel02 = fileOutputStream.getChannel();

        ByteBuffer byteBuffer = ByteBuffer.allocate(1024);

        //循环读取
        while(true){
            //清理缓冲区 非常重要
            byteBuffer.clear();
        int read=   channel01.read(byteBuffer);
        if(read==-1){
            break;
        }
        byteBuffer.flip();
        channel02.write(byteBuffer);
        }
fileInputStream.close();
        fileOutputStream.close();
    }
直接通过channel进行读写

public static void main(String[] args) throws IOException {
    FileInputStream fileInputStream = new FileInputStream("d:\eva.jpg");
    FileOutputStream fileOutputStream = new FileOutputStream("d:\eva2.jpg");
    FileChannel channel01 = fileInputStream.getChannel();
    FileChannel channel02 = fileOutputStream.getChannel();
    channel02.transferFrom(channel01,0,channel01.size());
 channel01.close();
 channel02.close();
 fileInputStream.close();
 fileOutputStream.close();

}