使用socket编程实现一个简单的文件服务器
使用socket编程实现一个简单的文件服务器。客户端程序实现put功能(将一个文件从本地传到文件服务器)和get功能(从文件服务器取一远程文件存为本地文件)。客户端和文件服务器不在同一台机器上。
put [-h hostname] [-p portname] local_filenameremote_filename
get [-h hostname] [-p portname] remote_filenamelocal_filename
程序如下：
客户端Client.java
package com.cn.gao; import java.net.*; import java.io.*; /** * * 用Socket实现文件服务器的客户端 * 包含发送文件和接收文件功能 * */ public class Client { private Socket client; private boolean connected; //构造方法 public Client(String host,int port){ try { //创建Socket对象 client = new Socket(host,port); System.out.println("服务器连接成功！"); this.connected = true; } catch (UnknownHostException e) { System.out.println("无法解析的主机！"); this.connected = false; } catch (IOException e) { System.out.println("服务器连接失败！"); this.connected = false; closeSocket(); } } //判断是否连接成功 public boolean isConnected(){ return connected; } //设置连接状态 public void setConnected(boolean connected){ this.connected = connected; } /** * 发送文件方法 * @param localFileName 本地文件的全路径名 * @param remoteFileName 远程文件的名称 */ public void sendFile(String localFileName, String remoteFileName){ DataOutputStream dos = null; //写Socket的输出流 DataInputStream dis = null; //读取本地文件的输入流 if(client==null) return; File file = new File(localFileName); //检查文件是否存在 if(!file.exists()){ System.out.println("本地文件不存在，请查看文件名是否写错！"); this.connected = false; this.closeSocket(); return; } try { //初始化本地文件读取流 dis = new DataInputStream(new BufferedInputStream(new FileInputStream(file))); //将指令和文件发送到Socket的输出流中 dos = new DataOutputStream(client.getOutputStream()); //将远程文件名发送出去 // System.out.println(remoteFileName); dos.writeUTF("put "+remoteFileName); //清空缓存，将文件名发送出去 dos.flush(); //开始发送文件 int bufferSize = 10240; byte[] buf = new byte[bufferSize]; int num =0; while((num=dis.read(buf))!=-1){ dos.write(buf, 0, num); } dos.flush(); System.out.println("文件发送成功！"); } catch (IOException e) { System.out.println("文件传输错误！"); closeSocket(); } finally{ try { dis.close(); dos.close(); } catch (IOException e) { System.out.println("输入输出错误！"); } } } /** * 接收文件方法 * @param remoteFileName 本地文件的全路径名 * @param localFileName 远程文件的名称 */ public void receiveFile(String remoteFileName, String localFileName){ DataOutputStream dos = null; //写Scoket的输出流 DataInputStream dis = null; //读Socket的输入流 DataOutputStream localdos = null; //写本地文件的输出流 if(client==null) return; try { localdos = new DataOutputStream(new BufferedOutputStream(new FileOutputStream(localFileName))); //将指令和文件名发送到Socket的输出流中 dos = new DataOutputStream(client.getOutputStream()); //将远程文件名发送出去 dos.writeUTF("get "+remoteFileName); dos.flush(); //开始接收文件 dis = new DataInputStream(new BufferedInputStream(client.getInputStream())); int bufferSize = 10240; byte[] buf = new byte[bufferSize]; int num = 0; while((num=dis.read(buf))!=-1){ localdos.write(buf, 0, num); } localdos.flush(); System.out.println("数据接收成功！"); } catch (FileNotFoundException e) { System.out.println("文件没有找到！"); closeSocket(); } catch (IOException e) { System.out.println("文件传输错误！"); } finally { try { dos.close(); localdos.close(); dis.close(); } catch (IOException e) { e.printStackTrace(); } } } //关闭端口 public void closeSocket(){ if(client!=null){ try { client.close(); } catch (IOException e) { e.printStackTrace(); } } } /** * 主方法调用上述方法 * @param args * 将本地文件上传到远程服务器 * put[-h hostname][-p portname]local_filename remote_filename * 从远程服务器上下载文件 * get[-h hostname][-p portname]remote_filename local_filename */ public static void main(String[] args){ //服务器默认端口为8888 if(args.length!=7){ System.out.println("参数数目不正确！"); return; } String hostName = args[2]; int port = 0; String localFileName = ""; String remoteFileName = ""; Client client = null; try { port = Integer.parseInt(args[4]); } catch (NumberFormatException e) { System.out.println("端口号输出格式错误！"); return; } if(args[0].equals("put")){ //上传文件 client = new Client(hostName,port); localFileName = args[5]; remoteFileName = args[6]; // System.out.println(remoteFileName); if(client.isConnected()){ client.sendFile(localFileName, remoteFileName); client.closeSocket(); } }else if(args[0].equals("get")){ //下载文件 client = new Client(hostName,port); localFileName = args[6]; remoteFileName = args[5]; if(client.isConnected()){ client.receiveFile(remoteFileName, localFileName); client.closeSocket(); } }else{ System.out.println("命令输入不正确，正确命令格式如下："); System.out.println("put -h hostname -p portname local_filename remote_filename"); System.out.println("get -h hostname -p portname remote_filename local_filename"); } } }
服务器端Server.java
package com.cn.gao; import java.io.*; import java.net.*; /** * 实现服务器端 * 用于接收上传的数据和供客户端下载数据 * @author DELL * */ public class Server { private int port; private String host; private String dirPath; private static ServerSocket server; public Server(int port,String dirPath){ this.port = port; this.dirPath = dirPath; this.server = null; } public void run(){ if(server==null){ try { server = new ServerSocket(port); } catch (IOException e) { e.printStackTrace(); } } System.out.println("服务已启动..."); while(true){ try { //通过ServerSocket的accept方法建立连接,并获取客户端的Socket对象 Socket client = server.accept(); if(client==null) continue; new SocketConnection(client,this.dirPath).run(); } catch (IOException e) { e.printStackTrace(); } } } /** * 实现服务器端的数据传输 * @author DELL * */ public class SocketConnection extends Thread{ private Socket client; private String filePath; public SocketConnection(Socket client, String filePath){ this.client = client; this.filePath = filePath; } public void run(){ if(client==null) return; DataInputStream in= null; //读取Socket的输入流 DataOutputStream dos = null; //写文件的输出流 DataOutputStream out = null; //写Socket的输出流 DataInputStream dis = null; //读文件的输入流 try { //访问Scoket对象的getInputStream方法取得客户端发送过来的数据流 in = new DataInputStream(new BufferedInputStream(client.getInputStream())); String recvInfo = in.readUTF(); //取得附带的指令及文件名 // System.out.println(recvInfo); String[] info = recvInfo.split(" "); String fileName = info[1]; //获取文件名 // System.out.println(fileName); if(filePath.endsWith("/")==false&&filePath.endsWith("\\")==false){ filePath+="\\"; } filePath += fileName; if(info[0].equals("put")){ //从客户端上传到服务器 //开始接收文件 dos = new DataOutputStream(new BufferedOutputStream(new FileOutputStream(new File(filePath)))); int bufferSize = 10240; byte[] buf = new byte[bufferSize]; int num =0; while((num=in.read(buf))!=-1){ dos.write(buf, 0, num); } dos.flush(); System.out.println("数据接收完毕！"); }else if(info[0].equals("get")){ //从服务器下载文件到客户端 dis = new DataInputStream(new BufferedInputStream(new FileInputStream(filePath))); //开始发送文件 int bufferSize = 10240; byte[] buf = new byte[bufferSize]; out = new DataOutputStream(client.getOutputStream()); int num =0; while((num=dis.read(buf))!=-1){ out.write(buf, 0, num); } out.flush(); System.out.println("发送成功！"); } } catch (IOException e) { e.printStackTrace(); } finally{ try { if(out!=null) out.close(); if(in!=null) in.close(); if(dos!=null) dos.close(); if(dis!=null) dis.close(); client.close(); } catch (IOException e) { e.printStackTrace(); } } } } public static void main(String[] args){ //设置服务器端口 int port = 8888; //设置服务器文件存放位置 String dirPath = "D:\\FTPService\\"; new Server(port,dirPath).run(); } }
参数输入方式示例
put -h 127.0.0.1 -p 8888 D:\\data.xls data.xls
get -h 127.0.0.1 -p 8888 data.xls D:\\data.xls
