Java socket Json

Question

更新

响应后有我更新的代码，我有一个问题，现在，我没有收到任何东西：

问题：

Connexion cliente reçue.
Lancement du traitement de la connexion cliente
Exception in thread "Thread-1" java.lang.NullPointerException
at cuisine.TimeServer.onResponseReceived(TimeServer.java:85)
at cuisine.ClientProcessor.run(ClientProcessor.java:43)
at java.base/java.lang.Thread.run(Thread.java:844)

时间服务器：85:回调

@Override
public void onResponseReceived(String response) {
// When the response is received from ClientProcessor
// this method is called (by ClientProcessor).
// Your response is the parameter String response.
callback.onResponse(response);
}

客户端处理器：43:

server.onResponseReceived(response);

一个客户端可以连接，但我什么都收不到：Json或短信。

这是我的新Java代码：

Main.java：

import cuisine.TimeServer.OnResponseReceivedListener;

public class main implements OnResponseReceivedListener {
public static void main(String[] args) throws IOException {
String host = "192.168.1.21";
int port = 8080;
TimeServer ts = new TimeServer(host, port);
ts.open();
System.out.println("------------Connected ! ------------");
}
@Override
public void onResponse(String response) {
doSomethingWith(response);
System.out.println("REPONSE : ");
System.out.println(response);
}
private void doSomethingWith(String response) {
System.out.println("REPONSE : ");
System.out.println(response);
}

}

我现在真的不知道如何使用响应，因为sysout"response"不在我的控制台中TimeServer.java：

...
import cuisine.ClientProcessor.Server;

public class TimeServer implements Server {
public interface OnResponseReceivedListener {
void onResponse(String response);
}
private int port = 2345;
private String host = "127.0.0.1";
private ServerSocket server = null;
private boolean isRunning = true;
private OnResponseReceivedListener callback;
public TimeServer() {
try {
server = new ServerSocket(port, 100, InetAddress.getByName(host));
} catch (UnknownHostException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}
public TimeServer(String pHost, int pPort) {
host = pHost;
port = pPort;
try {
server = new ServerSocket(port, 100, InetAddress.getByName(host));
} catch (UnknownHostException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}
public void open() {
Thread t =
new Thread(
new Runnable() {
public void run() {
while (isRunning == true) {
try {
Socket client = server.accept();
System.out.println("Connexion cliente reçue.");
ClientProcessor c = new ClientProcessor(client);
Thread t = new Thread(c);
// Don't forget to define the Server for ClientProcessor
c.addServer(TimeServer.this);
t.start();
} catch (IOException e) {
e.printStackTrace();
}
}
try {
server.close();
} catch (IOException e) {
e.printStackTrace();
server = null;
}
}
});
t.start();
}
@Override
public void onResponseReceived(String response) {
// When the response is received from ClientProcessor
// this method is called (by ClientProcessor).
// Your response is the parameter String response.
callback.onResponse(response);
}
public void addOnResponseReceivedListener(OnResponseReceivedListener listener) {
callback = listener;
}
public void removeOnResponseReceivedListener() {
callback = null;
}
public void close() {
isRunning = false;
}
}

ClientProcessor.java：

public class ClientProcessor implements Runnable {
public interface Server {
void onResponseReceived(String response);
}
private Socket sock;
private PrintWriter writer = null;
private BufferedInputStream reader = null;
public List<Dish> dish;
// Your server instance
private Server server;
public ClientProcessor(Socket pSock) {
this.sock = pSock;
}
public void run() {
System.err.println("Lancement du traitement de la connexion cliente");
boolean closeConnexion = false;
while (!sock.isClosed()) {
try {
writer = new PrintWriter(sock.getOutputStream());
reader = new BufferedInputStream(sock.getInputStream());
String response = read();
// report the response to TimeServer
server.onResponseReceived(response);
InetSocketAddress remote = (InetSocketAddress) sock.getRemoteSocketAddress();
String debug = "";
debug = "Thread : " + Thread.currentThread().getName() + ". ";
debug += "Demande de l'adresse : " + remote.getAddress().getHostAddress() + ".";
debug += " Sur le port : " + remote.getPort() + ".n";
debug += "t -> Commande reçue : " + response + "n";
System.err.println("n" + debug);
String toSend = "";
switch (response.toUpperCase()) {
case "ORDER":
toSend = "Dish";
break;
case "CLOSE":
toSend = "Communication terminée";
closeConnexion = true;
break;
default:
toSend = "Commande inconnu !";
break;
}
writer.write(toSend);
writer.flush();
if (closeConnexion) {
System.err.println("COMMANDE CLOSE DETECTEE ! ");
writer = null;
reader = null;
sock.close();
break;
}
} catch (SocketException e) {
System.err.println("LA CONNEXION A ETE INTERROMPUE ! ");
break;
} catch (IOException e) {
e.printStackTrace();
}
}
}
public void addServer(Server server) {
this.server = server;
}
private void removeServer() {
server = null;
}
// La méthode que nous utilisons pour lire les réponses
private String read() throws IOException {
String response = "";
int stream;
byte[] b = new byte[4096];
stream = reader.read(b);
response = new String(b, 0, stream);
return response;
}
}

谢谢，本杰明。

Answer 1

更新(更新Main.java(

更新No2(从Main.java中删除静态方法并使用Main对象(

编辑：(删除了以前关于套接字的回答(

这是json响应，现在我想在main中使用它：on同一包中的另一个类。

由于您已经说过您正在从客户端获得响应，但您不知道如何在Main类中操作它，因此您的问题与套接字无关。

解决方案：使用回调：

• ClientProcessor将向TimeServer报告响应
• CCD_ 6将向CCD_ 7报告该响应

让ClientProcessor知道服务器，并在获取响应时报告。

public class ClientProcessor implements Runnable {
public interface Server {
void onResponseReceived(String response);
}
private Socket sock;
private PrintWriter writer = null;
private BufferedInputStream reader = null;
public List<Dish> dish;
// Your server instance
private Server server;
public ClientProcessor(Socket pSock) {
this.sock = pSock;
}
public void run() {
System.err.println("Lancement du traitement de la connexion cliente");
boolean closeConnexion = false;
while (!sock.isClosed()) {
try {
writer = new PrintWriter(sock.getOutputStream());
reader = new BufferedInputStream(sock.getInputStream());
String response = read();
// report the response to TimeServer
server.onResponseReceived(response);
InetSocketAddress remote = (InetSocketAddress) sock.getRemoteSocketAddress();
String debug = "";
debug = "Thread : " + Thread.currentThread().getName() + ". ";
debug += "Demande de l'adresse : " + remote.getAddress().getHostAddress() + ".";
debug += " Sur le port : " + remote.getPort() + ".n";
debug += "t -> Commande reçue : " + response + "n";
System.err.println("n" + debug);
String toSend = "";
switch (response.toUpperCase()) {
case "ORDER":
toSend = "Dish";
break;
case "CLOSE":
toSend = "Communication terminée";
closeConnexion = true;
break;
default:
toSend = "Commande inconnu !";
break;
}
writer.write(toSend);
writer.flush();
if (closeConnexion) {
System.err.println("COMMANDE CLOSE DETECTEE ! ");
writer = null;
reader = null;
sock.close();
break;
}
} catch (SocketException e) {
System.err.println("LA CONNEXION A ETE INTERROMPUE ! ");
break;
} catch (IOException e) {
e.printStackTrace();
}
}
}
private void addServer(Server server) {
this.server = server;
}
private void removeServer() {
server = null;
}
// La méthode que nous utilisons pour lire les réponses
private String read() throws IOException {
String response = "";
int stream;
byte[] b = new byte[4096];
stream = reader.read(b);
response = new String(b, 0, stream);
return response;
}
}

现在转到TimeServer，让它知道Main(与前面的过程相同(。当收到来自ClientProcessor的响应时，您还必须向Main报告该响应。

public class TimeServer implements Server {
public interface OnResponseReceivedListener {
void onResponse(String response);
}
private int port = 2345;
private String host = "127.0.0.1";
private ServerSocket server = null;
private boolean isRunning = true;
private OnResponseReceivedListener callback;
public TimeServer() {
try {
server = new ServerSocket(port, 100, InetAddress.getByName(host));
} catch (UnknownHostException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}
public TimeServer(String pHost, int pPort) {
host = pHost;
port = pPort;
try {
server = new ServerSocket(port, 100, InetAddress.getByName(host));
} catch (UnknownHostException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}
public void open() {
Thread t =
new Thread(
new Runnable() {
public void run() {
while (isRunning == true) {
try {
Socket client = server.accept();
System.out.println("Connexion cliente reçue.");
Thread t = new Thread(new ClientProcessor(client));
// Don't forget to define the Server for ClientProcessor
t.addServer(TimeServer.this);
t.start();
} catch (IOException e) {
e.printStackTrace();
}
}
try {
server.close();
} catch (IOException e) {
e.printStackTrace();
server = null;
}
}
});
t.start();
}
@Override
public void onResponseReceived(String response) {
// When the response is received from ClientProcessor
// this method is called (by ClientProcessor).
// Your response is the parameter String response.
callback.onResponse(response);
}
public void addOnResponseReceivedListener(OnResponseReceivedListener listener) {
callback = listener;
}
public void removeOnResponseReceivedListener() {
callback = null;
}
public void close() {
isRunning = false;
}
}

最后，让你的Main听TimeServer，并在它收到响应时做一些事情。

public class Main implements OnResponseReceivedListener {
public static void main(String[] args) {
Main application = new Main();
TimeServer ts = application.createTimeServer();
ts.addOnResponseReceivedListener(application);
ts.open();
System.out.println("------------Connected ! ------------");
}
@Override
public void onResponse(String response) {
doSomethingWith(response);
}
private void doSomethingWith(String response) {
// Your logic for the response here...
}
private TimeServer createTimeServer() {
String host = "192.168.43.178";
int port = 8080;
return new TimeServer(host, port);
}
}