博客
关于我
java 零拷贝 分块传输大文件(解除8M限制)
阅读量:264 次
发布时间:2019-03-01

本文共 3378 字,大约阅读时间需要 11 分钟。

NIO-Based Zero Copy File Transfer Implementation

Server Side Implementation

package com.atguigu.nio.zerocopy;import java.io.IOException;import java.net.InetSocketAddress;import java.net.ServerSocket;import java.nio.ByteBuffer;import java.nio.channels.ServerSocketChannel;import java.nio.channels.SocketChannel;public class NewIOServer {    public static void main(String[] args) throws Exception {        InetSocketAddress address = new InetSocketAddress(7002);        ServerSocketChannel serverSocketChannel = ServerSocketChannel.open();        ServerSocket serverSocket = serverSocketChannel.socket();        serverSocket.bind(address);        ByteBuffer byteBuffer = ByteBuffer.allocate(4096);        while (true) {            SocketChannel socketChannel = serverSocketChannel.accept();            int readCount = 0;            while (-1 != readCount) {                try {                    readCount = socketChannel.read(byteBuffer);                } catch (Exception e) {                    break;                }                byteBuffer.rewind();            }        }    }}

Client Side Implementation

package com.atguigu.nio.zerocopy;import java.io.FileInputStream;import java.net.InetSocketAddress;import java.nio.channels.FileChannel;import java.nio.channels.SocketChannel;public class NewIOClient {    public static void main(String[] args) throws Exception {        SocketChannel socketChannel = SocketChannel.open();        socketChannel.connect(new InetSocketAddress("localhost", 7002));                String filename = "./test.avi";        FileChannel fileChannel = new FileInputStream(filename).getChannel();                long startTime = System.currentTimeMillis();        long totalSize = fileChannel.size();        long max_pkg = 8 * 1024 * 1024;        long cur_pos = 0;        long transSize = 0;                while (totalSize > max_pkg) {            long tmp = fileChannel.transferTo(cur_pos, max_pkg, socketChannel);            totalSize -= tmp;            cur_pos += tmp;            transSize += tmp;        }                if (totalSize > 0) {            long tmp = fileChannel.transferTo(cur_pos, totalSize, socketChannel);            transSize += tmp;        }                System.out.println("Total bytes transferred: " + transSize +                          " Elapsed time: " + (System.currentTimeMillis() - startTime));        fileChannel.close();    }}

Explanation

Server Side

  • Port Binding: The server binds to port 7002 using InetSocketAddress.
  • Reading Data: It uses a ByteBuffer of size 4096 to read data from connected clients.
  • Zero Copy Mechanism: The data is read directly from the socket channel into the buffer, leveraging zero copy functionality for efficient I/O operations.

Client Side

  • Connection Establishment: The client connects to the server at port 7002.
  • File Reading: It reads the file using FileInputStream and converts it to a FileChannel for NIO operations.
  • Zero Copy Transfer: The client transfers the file data to the server in chunks to handle large files efficiently. The transfer size is dynamically adjusted based on the maximum packet size (8MB in this implementation).
  • Performance Metrics: The total transfer time and bytes transferred are logged for verification purposes.

This implementation demonstrates the practical application of NIO's zero copy mechanism for high-performance file transfer scenarios.

转载地址:http://cqaa.baihongyu.com/

你可能感兴趣的文章