本文實(shí)例講述了Java使用Socket通信傳輸文件的方法。分享給大家供大家參考,具體如下:
網(wǎng)站建設(shè)哪家好,找創(chuàng)新互聯(lián)!專注于網(wǎng)頁設(shè)計(jì)、網(wǎng)站建設(shè)、微信開發(fā)、小程序設(shè)計(jì)、集團(tuán)企業(yè)網(wǎng)站建設(shè)等服務(wù)項(xiàng)目。為回饋新老客戶創(chuàng)新互聯(lián)還提供了葉城免費(fèi)建站歡迎大家使用!前面幾篇文章介紹了使用Java的Socket編程和NIO包在Socket中的應(yīng)用,這篇文章說說怎樣利用Socket編程來實(shí)現(xiàn)簡(jiǎn)單的文件傳輸。
這里由于前面一片文章介紹了NIO在Socket中的應(yīng)用,所以這里在讀寫文件的時(shí)候也繼續(xù)使用NIO包,所以代碼看起來會(huì)比直接使用流的方式稍微復(fù)雜一點(diǎn)點(diǎn)。
下面的示例演示了客戶端向服務(wù)器端發(fā)送一個(gè)文件,服務(wù)器作為響應(yīng)給客戶端回發(fā)一個(gè)文件。這里準(zhǔn)備兩個(gè)文件E:/test/server_send.log和E:/test/client.send.log文件,在測(cè)試完畢后在客戶端和服務(wù)器相同目錄下會(huì)多出兩個(gè)文件E:/test/server_receive.log和E:/test/client.receive.log文件。
下面首先來看看Server類,主要關(guān)注其中的sendFile和receiveFile方法。
package com.googlecode.garbagecan.test.socket.nio; import java.io.File; import java.io.FileInputStream; import java.io.FileOutputStream; import java.io.IOException; import java.net.InetSocketAddress; import java.nio.ByteBuffer; import java.nio.channels.ClosedChannelException; import java.nio.channels.FileChannel; import java.nio.channels.SelectionKey; import java.nio.channels.Selector; import java.nio.channels.ServerSocketChannel; import java.nio.channels.SocketChannel; import java.util.Iterator; import java.util.logging.Level; import java.util.logging.Logger; public class MyServer4 { private final static Logger logger = Logger.getLogger(MyServer4.class.getName()); public static void main(String[] args) { Selector selector = null; ServerSocketChannel serverSocketChannel = null; try { // Selector for incoming time requests selector = Selector.open(); // Create a new server socket and set to non blocking mode serverSocketChannel = ServerSocketChannel.open(); serverSocketChannel.configureBlocking(false); // Bind the server socket to the local host and port serverSocketChannel.socket().setReuseAddress(true); serverSocketChannel.socket().bind(new InetSocketAddress(10000)); // Register accepts on the server socket with the selector. This // step tells the selector that the socket wants to be put on the // ready list when accept operations occur, so allowing multiplexed // non-blocking I/O to take place. serverSocketChannel.register(selector, SelectionKey.OP_ACCEPT); // Here's where everything happens. The select method will // return when any operations registered above have occurred, the // thread has been interrupted, etc. while (selector.select() > 0) { // Someone is ready for I/O, get the ready keys Iteratorit = selector.selectedKeys().iterator(); // Walk through the ready keys collection and process date requests. while (it.hasNext()) { SelectionKey readyKey = it.next(); it.remove(); // The key indexes into the selector so you // can retrieve the socket that's ready for I/O doit((ServerSocketChannel) readyKey.channel()); } } } catch (ClosedChannelException ex) { logger.log(Level.SEVERE, null, ex); } catch (IOException ex) { logger.log(Level.SEVERE, null, ex); } finally { try { selector.close(); } catch(Exception ex) {} try { serverSocketChannel.close(); } catch(Exception ex) {} } } private static void doit(final ServerSocketChannel serverSocketChannel) throws IOException { SocketChannel socketChannel = null; try { socketChannel = serverSocketChannel.accept(); receiveFile(socketChannel, new File("E:/test/server_receive.log")); sendFile(socketChannel, new File("E:/test/server_send.log")); } finally { try { socketChannel.close(); } catch(Exception ex) {} } } private static void receiveFile(SocketChannel socketChannel, File file) throws IOException { FileOutputStream fos = null; FileChannel channel = null; try { fos = new FileOutputStream(file); channel = fos.getChannel(); ByteBuffer buffer = ByteBuffer.allocateDirect(1024); int size = 0; while ((size = socketChannel.read(buffer)) != -1) { buffer.flip(); if (size > 0) { buffer.limit(size); channel.write(buffer); buffer.clear(); } } } finally { try { channel.close(); } catch(Exception ex) {} try { fos.close(); } catch(Exception ex) {} } } private static void sendFile(SocketChannel socketChannel, File file) throws IOException { FileInputStream fis = null; FileChannel channel = null; try { fis = new FileInputStream(file); channel = fis.getChannel(); ByteBuffer buffer = ByteBuffer.allocateDirect(1024); int size = 0; while ((size = channel.read(buffer)) != -1) { buffer.rewind(); buffer.limit(size); socketChannel.write(buffer); buffer.clear(); } socketChannel.socket().shutdownOutput(); } finally { try { channel.close(); } catch(Exception ex) {} try { fis.close(); } catch(Exception ex) {} } } }