java+Socket实现客户端服务器端的登录通信

java+Socket实现客户端服务器端的登录通信 服务器和客户端都是自己再网上copy的代码，有一个bug就是当客户端退出的时候会报错，这个bug很容易解决。先来看看我们的服务器端代码:(服务器端用了数据库的查询登陆) package Test; import java.io.IOException; import java.net.InetSocketAddress; import java.net.ServerSocket; import java.nio.ByteBuffer; import java.nio.channels.SelectionKey; import java.nio.channels.Selector; import java.nio.channels.ServerSocketChannel; import java.nio.channels.SocketChannel; import java.sql.ResultSet; import java.sql.SQLException; import java.util.Iterator; import java.util.Set; public class Server { public static final int serverport =5555; public static final String isack="ack"; public static final String isnak="nak"; private ByteBuffer echobuffer=ByteBuffer.allocate(1024); public Server() { } public static void main(String[] args) { new Server().buildserver(); } public void buildserver(){ try { ServerSocketChannel ssc=ServerSocketChannel.open(); ssc.configureBlocking(false); ServerSocket ss=ssc.socket(); ss.bind(new InetSocketAddress("127.0.0.1",serverport)); Selector selector=Selector.open(); SelectionKey skey=ssc.register(selector,SelectionKey.OP_ACCEPT); while(true) { int num=selector.select(); if(num<1) { continue; } Set selectedKeys=selector.selectedKeys(); Iterator it=selectedKeys.iterator(); while(it.hasNext()) { SelectionKey key=(SelectionKey) it.next(); if((key.readyOps()&SelectionKey.OP_ACCEPT)==SelectionKey.OP_ACCEPT) { ServerSocketChannel serverchannel=(ServerSocketChannel) key.channel(); SocketChannel sc=serverchannel.accept(); sc.configureBlocking(false); SelectionKey newKey=sc.register(selector,SelectionKey.OP_READ); it.remove(); System.out.print("get connection from"+sc); } else{ if((key.readyOps()&SelectionKey.OP_READ)==SelectionKey.OP_READ) { SocketChannel sc=(SocketChannel) key.channel(); int bytesEchoed=0; while((bytesEchoed=sc.read(echobuffer))>0) { System.out.println("bytesEchoed"+bytesEchoed); } echobuffer.flip(); System.out.println("limet "+echobuffer.limit()); byte [] content =new byte[echobuffer.limit()]; echobuffer.get(content); String result=new String(content); doPost(result,sc); echobuffer.clear(); it.remove(); } } } } } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } } public void doPost(String str, SocketChannel sc) { boolean isok=false; int index=str.indexOf('|'); if(index>0) { String name=str.substring(0,index); String pswd=str.substring(index+1); String sql="select name,password from login where name='"+name+"'and password='"+pswd+"'"; SqlConn sc1=new SqlConn(); ResultSet rs=sc1.getResult(sql); boolean f=false; try { f=rs.first(); } catch (SQLException e1) { // TODO Auto-generated catch block e1.printStackTrace(); } if(pswd==null) { pswd=""; }if(name!=null) { if(f) { isok=true; } else{ isok=false; } String result=""; if(isok) { result="ack"; } else{ result="nak"; } ByteBuffer bb=ByteBuffer.allocate(result.length()); bb.put(result.getBytes()); bb.flip(); try { sc.write(bb); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } bb.clear(); } } } } 下面是客户端: package Test; import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import java.io.IOException; import java.io.InputStream; import java.io.OutputStream; import java.net.Socket; import java.net.UnknownHostException; import javax.swing.JButton; import javax.swing.JFrame; import javax.swing.JLabel; import javax.swing.JTextField; public class client extends JFrame{ private JLabel jLabel1; private JTextField usertext; private JLabel jLabel2; private JButton loginbutton; private JLabel hint; private JTextField passtext; String name; String password; public client() { { getContentPane().setLayout(null); } { jLabel1 = new JLabel(); getContentPane().add(jLabel1); jLabel1.setText("\u7528\u6237\u540d"); jLabel1.setBounds(39, 39, 63, 18); } { usertext = new JTextField(); getContentPane().add(usertext); usertext.setBounds(109, 37, 156, 22); } { jLabel2 = new JLabel(); getContentPane().add(jLabel2); jLabel2.setText("\u5bc6\u7801"); jLabel2.setBounds(39, 77, 38, 18); } { passtext = new JTextField(); getContentPane().add(passtext); passtext.setBounds(109, 75, 156, 22); } { loginbutton = new JButton(); getContentPane().add(loginbutton); loginbutton.setText("\u767b\u9646"); loginbutton.setBounds(90, 113, 91, 28); loginbutton.addActionListener(new ActionListener(){ public void actionPerformed(ActionEvent e) { name=usertext.getText().trim(); password=passtext.getText().trim(); if(password.equals("")) { password=""; } if(name!=null&&name.length()>0) { hint.setText("正在验证客户端，请稍后......"); start(); } } public void start() { new Thread(new Runnable(){ public void run() { try { Socket s=new Socket("localhost",5555); OutputStream os; InputStream is; os=s.getOutputStream(); os.write(name.getBytes()); os.write('|'); os.write(password.getBytes()); os.flush(); Thread.sleep(1000); is=s.getInputStream(); int len=is.available(); System.out.println("length: "+len); byte[] bytes=new byte[len]; is.read(bytes); String result=new String(bytes); System.out.println("result: "+result); if(result.equals("ack")) { hint.setText("验证成功，欢迎光临"); }else{ passtext.setText(null); hint.setText("用户名或密码有误，请重新 输入"); } } catch (UnknownHostException e) { // TODO Auto-generated catch block e.printStackTrace(); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } catch (InterruptedException e) { // TODO Auto-generated catch block e.printStackTrace(); } } }).start(); } }); } { hint = new JLabel(); getContentPane().add(hint); hint.setBounds(90, 8, 172, 23); } { this.setSize(318, 188); setVisible(true); } } public static void main(String[] args) { new client(); } } 下面是数据库的链接: package Test; import java.sql.Connection; import java.sql.DriverManager; import java.sql.ResultSet; import java.sql.SQLException; import java.sql.Statement; public class SqlConn { String driverName = "com.microsoft.sqlserver.jdbc.SQLServerDriver"; String dbURL = "jdbc:sqlserver://localhost:1433; DatabaseName=project"; String userName = "sa"; String userPwd = "123"; Connection con; ResultSet rs; Statement stmt; public SqlConn() { try{ Class.forName(driverName); con=DriverManager.getConnection(dbURL, userName, userPwd); stmt=con.createStatement(ResultSet.TYPE_SCROLL_SENSITIVE,ResultSet.CONCUR_UPDATABLE); } catch ( ClassNotFoundException cnfex ) { System.err.println("Failed To Connect DataBase." ); cnfex.printStackTrace(); System.exit( 1 ); // terminate program } catch(SQLException sqle) { System.out.println(sqle.toString()); } } public ResultSet getResult(String sql) { try{ rs=stmt.executeQuery(sql); return rs; } catch(SQLException sqle) { System.out.println(sqle.toString()); return null; } } public boolean updateSql(String strSQL) { try{ stmt.executeUpdate(strSQL); con.commit(); return true; } catch(SQLException sqle) { System.out.println(sqle.toString()); return false; } } public void closeConnection() { try { con.close(); } catch(SQLException sqle) { System.out.println(sqle.toString()); } } }