Java-Code-Chap11.zip_forth8x9_storyjk4_网络编程

import java.net.*; import java.io.*; import java.awt.*; import java.awt.event.*; import javax.swing.*; public class ClientFrame extends JFrame implements Runnable,ActionListener { JButton connection,computer; JTextField inputA,inputB,inputC; JTextArea showResult; Socket socket = null; DataInputStream in = null; DataOutputStream out = null; Thread thread; public ClientFrame() { // --- socket = new Socket(); //待连接的套接字 // --- connection = new JButton("连接服务器"); connection.addActionListener(this); // --- computer = new JButton("求方程的根"); computer.setEnabled(false); //没有和服务器连接之前，该按钮不可用 computer.addActionListener(this); // --- inputA = new JTextField("0",12); inputB = new JTextField("0",12); inputC = new JTextField("0",12); // --- Box boxV1 = Box.createVerticalBox(); boxV1.add(new JLabel("输入2次项系数")); boxV1.add(new JLabel("输入1次项系数")); boxV1.add(new JLabel("输入常数项")); Box boxV2 = Box.createVerticalBox(); boxV2.add(inputA); boxV2.add(inputB); boxV2.add(inputC); Box baseBox = Box.createHorizontalBox(); baseBox.add(boxV1); baseBox.add(boxV2); // --- showResult = new JTextArea(8,18); // --- Container con = getContentPane(); con.setLayout(new FlowLayout()); con.add(connection); con.add(baseBox); con.add(computer); con.add(new JScrollPane(showResult)); // --- setBounds(100,100,360,310); setVisible(true); setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); // --- thread = new Thread(this); } public void run() { while(true) { try { double root1 = in.readDouble(); //堵塞状态，除非读取到信息 double root2 = in.readDouble(); showResult.append("\n两个根:\n"+root1+"\n"+root2); showResult.setCaretPosition((showResult.getText()).length()); } catch(IOException e) { showResult.setText("与服务器已断开"); computer.setEnabled(false); break; } } } public void actionPerformed(ActionEvent e) { if(e.getSource()==connection) { try { if(socket.isConnected()) { } else { // --- InetAddress address = InetAddress.getByName("127.0.0.1"); InetSocketAddress socketAddress = new InetSocketAddress(address,4332); // --- socket.connect(socketAddress); // --- in=new DataInputStream(socket.getInputStream()); // --- out=new DataOutputStream(socket.getOutputStream()); // --- computer.setEnabled(true); //thread.start(); } } catch (IOException ee) { System.out.println(ee); socket=new Socket(); } } if(e.getSource()==computer) { try { double a = Double.parseDouble(inputA.getText()), b = Double.parseDouble(inputB.getText()), c = Double.parseDouble(inputC.getText()); double disk=b*b-4*a*c; if(disk>=0) { out.writeDouble(a); out.writeDouble(b); out.writeDouble(c); // !!! double root1 = in.readDouble(); //堵塞状态，除非读取到信息 double root2 = in.readDouble(); showResult.append("\n两个根:\n"+root1+"\n"+root2); showResult.setCaretPosition((showResult.getText()).length()); } else { inputA.setText("此2次方程无实根"); } } catch(Exception ee) { inputA.setText("请输入数字字符"); } } } public static void main(String args[]) { ClientFrame win = new ClientFrame(); } }