我实际上正在尝试创建一个程序：
public void setUpNetwork(){
try {
Socket sock = new Socket("localhost", 1101);
InputStreamReader read = new InputStreamReader(sock.getInputStream());
buff = new BufferedReader(read);
write = new PrintWriter(sock.getOutputStream());
System.out.println("Network Established");
} catch (UnknownHostException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}
}
在这里，一旦建立了套接字连接，我就会尝试将用户输入的数据传递给打印流，然后在控制台中打印出数据。
我的服务器类只有这么多：
ServerSocket server = new ServerSocket(1101);
Socket socket = server.accept();
当我运行它时（在运行时，我首先运行服务器，然后运行 ChatSetUp 类），控制台上没有打印任何内容！是否因为 sersock.accept() 提供了一个具有不同端口的套接字连接，并且客户端无法与服务器通信？如果是这样，我需要将套接字对象从服务器传递到不同类中的 setUpNetwork()，以便我可以在其上创建输入流。我该怎么做？
编辑：
我对整个程序进行了更多修改！我正在使用 Swing 创建 GUI，其中当用户在文本字段中输入文本并点击发送时，它会触发侦听器，这就是我将文本添加到 PrintWriter 的地方。整个代码如下： ....和 setUpNetwork() 也是这个类的一部分（不包括在下面）
编辑：在同一程序中包含服务器代码并为服务器启动一个新线程。
public class ChatGraphs {
JTextField field;
JTextArea area;
PrintWriter write;
BufferedReader buff;
Socket sock;
public static void main(String[] args) {
ChatGraphs grap = new ChatGraphs();
grap.doIt();
}
private void doIt() {
JFrame frame = new JFrame();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JPanel allPanel = new JPanel();
allPanel.setLayout(new BoxLayout(allPanel, BoxLayout.Y_AXIS));
JPanel areaPanel = new JPanel();
areaPanel.setLayout(new FlowLayout());
JLabel alabel = new JLabel("Chats");
area = new JTextArea(20, 50);
area.setEditable(false);
areaPanel.add(alabel);
areaPanel.add(area);
JPanel textPanel = new JPanel();
textPanel.setLayout(new FlowLayout());
JLabel flabel = new JLabel("Enter");
field = new JTextField(20);
JButton button = new JButton("Send");
button.addActionListener(new ButtonListen());
textPanel.add(flabel);
textPanel.add(field);
textPanel.add(button);
allPanel.add(areaPanel);
allPanel.add(textPanel);
ConnectServer con = new ConnectServer();
Thread t = new Thread(con);
t.start();
AddData add = new AddData();
Thread t1 = new Thread(add);
t1.start();
//setUpServer();
setUpClient();
frame.setSize(700,500);
frame.setVisible(true);
frame.getContentPane().add(allPanel);
}
public class ButtonListen implements ActionListener{
@Override
public void actionPerformed(ActionEvent arg0) {
write.println(field.getText());
write.flush();
field.setText("");
field.setRequestFocusEnabled(true);
}
}
private void setUpClient(){
try {
sock = new Socket("localhost", 1101);
InputStreamReader read = new InputStreamReader(sock.getInputStream());
buff = new BufferedReader(read);
System.out.println("Network Established");
} catch (UnknownHostException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}
public class AddData implements Runnable{
@Override
public void run() {
String line="";
try {
while((line=buff.readLine())!=null){
System.out.println("Another net");
area.append(line);
}
buff.close();
write.close();
sock.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
public class ConnectServer implements Runnable{
public void run() {
ServerSocket sersock = null;
Socket sock = null;
try {
sersock = new ServerSocket(1101);
sock = sersock.accept();
write = new PrintWriter(sock.getOutputStream());
sersock.close();
sock.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
}
我得到的例外是：
Exception in thread "Thread-2" java.lang.NullPointerException
at org.sockets.ChatGraphs$AddData.run(ChatGraphs.java:120) // This line is : while((line=buff.readLine())!=null)
at java.lang.Thread.run(Unknown Source)
Network Established