Question

java聊天小程序，进来帮帮我！

以下是我的程序代码，老是不知道为什么不能聊天，高手帮帮我。。。。555555~~~~~
服务器端：
import:略
class wangluo1 extends JFrame implements ActionListener{
JFrame frame=new JFrame();
JPanel panel1=new JPanel();
JPanel panel2=new JPanel();
JTextArea text1=new JTextArea(30,30);
JTextArea text2=new JTextArea(3,25);
JButton sent=new JButton("发送");
InputStream in;
OutputStream out;
Socket client;
ServerSocket server;
public wangluo1(){
add("South",panel2);
add(panel1);
panel1.add(text1);
panel2.setLayout(new FlowLayout());
panel2.add(text2);
panel2.add(sent);
sent.addActionListener(this);
addWindowListener(new WindowAdapter(){
public void windowClosing(WindowEvent e){
System.exit(0);
}
});
pack();
setVisible(true);
try{
server=new ServerSocket(10000);
client=server.accept();
in=client.getInputStream();
out=client.getOutputStream();
text1.append("已连接");
}catch(IOException ioe){}
while(true){
try{

byte[]buf=new byte[256];
in.read(buf);
String str=new String(buf);
text1.append("客户机说："+str);
text1.append("\n");
}catch(IOException e){
}
}
}
public static void main(String[] args) {
new wangluo1();
}
public void actionPerformed(ActionEvent e) {

try{
String s=text2.getText();
byte[]buf=s.getBytes();
text2.setText("");
out.write(buf);
text1.append("\n"+s);
}catch(IOException ie){
}
}
}
客户端：
导入略
public class wangluo2 extends JFrame implements ActionListener{
JFrame frame=new JFrame();
Socket client;
OutputStream os;
InputStream is;
String s;
JTextArea text3=new JTextArea(30,30);
JTextArea text4=new JTextArea(3,25);
JPanel panel1=new JPanel();
JPanel panel2=new JPanel();
JButton clientsent=new JButton("发送");
public wangluo2(){
add("South",panel2);
add(panel1);
panel1.add(text3);
panel2.setLayout(new FlowLayout());
panel2.add(text4);
panel2.add(clientsent);
pack();
setVisible(true);
addWindowListener(new WindowAdapter(){
public void windowClosing(WindowEvent e){
System.exit(0);
}
});
clientsent.addActionListener(this);
try{
client=new Socket("127.0.0.1",10000);
text3.append("已连接"); is=client.getInputStream();
os=client.getOutputStream();
}catch(IOException ioe){}

while(true){
try{
byte[]buf=new byte[256];
is.read(buf);
String str=new String(buf);
text3.append("服务器说："+str);
text3.append("\n");
}catch(IOException e){
}
}
}
public static void main(String[] args) {
new wangluo2();
}
public void actionPerformed(ActionEvent e) {
try{
String str=text4.getText();
byte[]buf=str.getBytes();
text4.setText("");
os.write(buf);
text3.append("\n"+str);
}catch(Exception ee){
}
}
}
我在客户端输入的东西一按发送，服务器端的信息马上被清空。。反过来在服务器端输入，客户端的马上又被清空。。到最后什么都木有了。。。5555555~~~~~~

Answer 1

程序错在两个主要的地方：
1.读写流竟然没有关闭？？？而且在关闭之前应该先Flush()，这是因为用读写流的时候，其实数据是先被读到了内存中，然后用数据写到文件中，当你数据读完的时候不代表你的数据已经写完了，因为还有一部分有可能会留在内存这个缓冲区中。这时候如果你调用了 Close()方法关闭了读写流，那么这部分数据就会丢失，所以应该在关闭读写流之前先Flush()，先清空数据。
2.你在接收发送内容的时候用了
byte[] buf = new byte[256];
is.read(buf);
String str = new String(buf);
简单来说，比如你发送的内容是123，那么最后的str串是“123+253个空格”
在用append追加的时候是看不到的，所以在你打印str的时候去掉空格
text1.append("客户机说：" + "\n" +str.trim());
text3.append("客户机说：" + "\n" +str.trim());

这样就可以了，程序还有很多需要完善的地方，我只是给你小改了下：
服务器端：
class wangluo1 extends JFrame implements ActionListener {
JFrame frame = new JFrame();
JPanel panel1 = new JPanel();
JPanel panel2 = new JPanel();
JTextArea text1 = new JTextArea(30, 30);
JTextArea text2 = new JTextArea(3, 25);
JButton sent = new JButton("发送");
InputStream in;
OutputStream out;
Socket client;
ServerSocket server;

public wangluo1() {
add("South", panel2);
add(panel1);
panel1.add(text1);
panel2.setLayout(new FlowLayout());
panel2.add(text2);
panel2.add(sent);
sent.addActionListener(this);
addWindowListener(new WindowAdapter() {
public void windowClosing(WindowEvent e) {
try {
in.close();
out.close();
} catch (IOException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}
System.exit(0);
}
});
pack();
setVisible(true);
this.setTitle("服务器说：");
try {
server = new ServerSocket(10000);
client = server.accept();
in = client.getInputStream();
out = client.getOutputStream();
text1.append("已连接"+"\n");
} catch (IOException ioe) {
}
while (true) {
try {

byte[] buf = new byte[256];
in.read(buf);
String str = new String(buf);
text1.append("客户端说：" + "\n" +str.trim());
text1.append("\n");
} catch (IOException e) {
}
}

}

public static void main(String[] args) {
new wangluo1();
}

public void actionPerformed(ActionEvent e) {

try {
String s = text2.getText();
byte[] buf = s.getBytes();
text2.setText("");
out.write(buf);
out.flush();
text1.append("服务器说："+"\n" + s + "\n");
} catch (IOException ie) {
}
}
}

客户端：
public class wangluo2 extends JFrame implements ActionListener {
JFrame frame = new JFrame();
Socket client;
OutputStream os;
InputStream is;
String s;
JTextArea text3 = new JTextArea(30, 30);
JTextArea text4 = new JTextArea(3, 25);
JPanel panel1 = new JPanel();
JPanel panel2 = new JPanel();
JButton clientsent = new JButton("发送");

public wangluo2() {
add("South", panel2);
add(panel1);
panel1.add(text3);
panel2.setLayout(new FlowLayout());
panel2.add(text4);
panel2.add(clientsent);
pack();
setVisible(true);
this.setLocation(500, 0);
this.setTitle("客户端");
addWindowListener(new WindowAdapter() {
public void windowClosing(WindowEvent e) {
try {
is.close();
os.close();
} catch (IOException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}

System.exit(0);
}
});
clientsent.addActionListener(this);
try {
client = new Socket("127.0.0.1", 10000);
text3.append("已连接"+"\n");
is = client.getInputStream();
os = client.getOutputStream();
} catch (IOException ioe) {
}

while (true) {
try {
byte[] buf = new byte[256];
is.read(buf);
String str = new String(buf);
text3.append("服务器说：" + "\n" + str.trim());
text3.append("\n");

} catch (IOException e) {
}
}
}

public static void main(String[] args) {
new wangluo2();

}

public void actionPerformed(ActionEvent e) {
try {
String str = text4.getText();
byte[] buf = str.getBytes();
text4.setText("");
os.write(buf);
os.flush();
text3.append("客户端说："+"\n" + str + "\n");
} catch (Exception ee) {
}
}
}

Answer 2

没错 每个读取的时候都要flush
建议你用线程来处理

Answer 3

OutputStream在write()之后要flush()

Answer 4

new os and is

Answer 5

1楼正确。