import java.io.*;
public class Input {
public static void main(String[] args) throws IOException{
byte buf[]=new byte[20];
try{
System.in.read(buf);
}catch(IOException e){
System.out.println(e.toString());这行tostring怎么解释啊?
}
String str=new String(buf,0);
System.out.println(str);
}
}
书上的代码 求详细解释!!!
import java.io.FileReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.ServerSocket;
import java.net.Socket;import javax.swing.JLabel;
import javax.swing.JTextArea;
public class GetMessage extends Thread{
private int i;
String v;JLabel label=null;
private JTextArea text;
public GetMessage(int i,JTextArea text) {this.i=i;
this.text=text;
}public void run(){
try {
ServerSocket so = new ServerSocket(i);
Socket s = so.accept();
while(true){
InputStreamReader i = new InputStreamReader(s.getInputStream());
BufferedReader b = new BufferedReader(i);
v= b.readLine();
text.append("对方说"+v+"\n");
}
} catch (IOException e) {
//label.setText("对方已经下线");
text.append("对方下线了");
}
}
}SendMessage.java客户端:
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintStream;
import java.net.Socket;
import java.net.UnknownHostException;import javax.swing.JLabel;
import javax.swing.JTextArea;
import javax.swing.JTextField;
public class SendMessage extends Thread {
private String ip;
private int i;
Socket s = null;
JLabel label=null;
JTextField text;
JTextArea text1;
public SendMessage(String ip,int i,JTextArea text1) {
// TODO Auto-generated constructor stub
this.ip=ip;
this.i=i;
this.text1=text1;}
public void run(){
while(true){
try {
s = new Socket(ip,i);
text1.setText("连接成功"+"\n");
break;
} catch (Exception e) {
try {
Thread.sleep(1000);
} catch (InterruptedException e1) {
System.out.println("出错了。");
}
}
}
}
public void send(String message)
{
try {PrintStream p = new PrintStream(s.getOutputStream());p.println(message);
} catch (Exception e1) {
System.out.println("异常"+e1.getMessage());
}
}
}Test.java 简单的界面和测试类
import java.awt.*;import java.awt.event.*;
import java.io.ByteArrayInputStream;
import java.io.InputStream;
import java.util.*;import javax.swing.*;
import javax.swing.event.*;
class WindowTextArea extends JFrame implements ActionListener
{ String s;
JTextArea text1;
JTextArea text2;
JButton button1,button2,button3;
SendMessage t2;
GetMessage t1;
JLabel lable1,lable2;
JTextField text; WindowTextArea()
{ this.s=s;
lable1=new JLabel("对方ip");
text=new JTextField(20);
text1=new JTextArea(6,18);
text2=new JTextArea(6,18);
text2.setEditable(false);
button1=new JButton("发送");
button2=new JButton("关闭");
button3=new JButton("确定ip");
setBounds(100,100,450,300);
setVisible(true);
Container con=getContentPane();
con.setLayout(new FlowLayout());
con.add(lable1);
con.add(text);
con.add(button3);
con.add(new JScrollPane(text1));
con.add(new JScrollPane(text2));
con.add(button1);
con.add(button2);
button1.addActionListener(this);
button2.addActionListener(this);
button3.addActionListener(this);
con.validate();
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}
public void runthread(String ip)
{
t1 = new GetMessage(4066,text2);
t1.start();
t2=new SendMessage(ip,4066,text2);
t2.start();
}
public void actionPerformed(ActionEvent e) {
// TODO Auto-generated method stub
if(e.getSource()==button2)
{
System.exit(0);
}
if(e.getSource()==button1)
{
text2.append(text1.getText()+"\n");
t2.send(text1.getText());
text1.setText("");
}
if(e.getSource()==button3)
{
s=text.getText();runthread(s);
}
}
}
public class Test {/**
* @param args
*/
public static void main(String[] args) {new WindowTextArea();}
}
new WindowTextArea();}
}向对方发送信息之前必须输入对方ip和点击确定ip按钮,文本区显示“连接成功”
然后可以发送信息