Client – server TCP, implementare client Java, server C sub Linux/Unix

Clienti Java (doua versiuni) pentru problema precedenta:

Client.java

import java.net.*;
import java.io.*;

public class Client {

public static void main(String args[]) throws Exception {
  Socket c = new Socket("127.0.0.1", 1234);
  BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));
  int a, b, s;
  System.out.print("a = ");
  a = Integer.parseInt(reader.readLine());
  System.out.print("b = ");
  b = Integer.parseInt(reader.readLine());
  
  DataInputStream socketIn = new DataInputStream(c.getInputStream());
  DataOutputStream socketOut = new DataOutputStream(c.getOutputStream());
  
  socketOut.writeShort(a);
  socketOut.writeShort(b);
  socketOut.flush();
  
  s = socketIn.readUnsignedShort();
  System.out.println("s = " + s);
  
  reader.close();
  c.close();  
}

}

import java.net.*;

import java.io.*;

public class Client {

public static void main(String args[]) throws Exception {

Socket c = new Socket("127.0.0.1", 1234);

BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));

int a, b, s;

System.out.print("a = ");

a = Integer.parseInt(reader.readLine());

System.out.print("b = ");

b = Integer.parseInt(reader.readLine());

DataInputStream socketIn = new DataInputStream(c.getInputStream());

DataOutputStream socketOut = new DataOutputStream(c.getOutputStream());

socketOut.writeShort(a);

socketOut.writeShort(b);

socketOut.flush();

s = socketIn.readUnsignedShort();

System.out.println("s = " + s);

reader.close();

c.close();

}

Client2.java

import java.net.*;
import java.io.*;

public class Client2 {

    private static final String SERVER_ADDRESS = "127.0.0.1";
    private static final int SERVER_PORT = 1234;
    private static final int UNSIGNED_SHORT_MAX_VALUE = 65535;
    private static final int UNSIGNED_SHORT_MIN_VALUE = 0;

    public static void main(String args[]) {
        Socket socket = null;
        BufferedReader reader = null;
        try {
            reader = new BufferedReader(new InputStreamReader(System.in));
            socket = new Socket(SERVER_ADDRESS, SERVER_PORT);
            int a = readUnsignedShort("a = ", reader);
            int b = readUnsignedShort("b = ", reader);
            writeIntegersToSocket(a, b, socket);
            readIntegersSumFromSocket(socket);
        } catch (IOException e) {
            System.err.println("Cautgh exception " + e.getMessage());
        } finally {
            closeStreams(socket,reader);
        }
    }

    private static void readIntegersSumFromSocket(Socket c) throws IOException {
        DataInputStream socketIn = new DataInputStream(c.getInputStream());
        int s = socketIn.readUnsignedShort();
        System.out.println("s = " + s);
    }

    private static void writeIntegersToSocket(int a, int b, Socket c) throws IOException {
        DataOutputStream socketOut = new DataOutputStream(c.getOutputStream());
        socketOut.writeShort(a);
        socketOut.writeShort(b);
        socketOut.flush();
    }

    private static int readUnsignedShort(String message, BufferedReader reader) throws IOException {
        int unsignedShortNumber = 0;
        System.out.print(message);
        try {
            unsignedShortNumber = Integer.parseInt(reader.readLine());
            if (unsignedShortNumber < UNSIGNED_SHORT_MIN_VALUE || unsignedShortNumber > UNSIGNED_SHORT_MAX_VALUE) {
                throw new IllegalArgumentException("The given number must be unsigned short [0..65535]!");
            }
        } catch (NumberFormatException e) {
            System.err.println("The given input is not an integer!");
        }
        return unsignedShortNumber;
    }

    private static void closeStreams(Socket socket, BufferedReader reader) {
        if (socket != null) {
            try {
                socket.close();
            } catch (IOException e) {
                System.err.println("Could not close socket!");
            }
        }
        if (reader != null) {
            try {
                reader.close();
            } catch (IOException e) {
                System.err.println("Could not close reader!");
            }
        }
    }

}

import java.net.*;

import java.io.*;

public class Client2 {

private static final String SERVER_ADDRESS = "127.0.0.1";

private static final int SERVER_PORT = 1234;

private static final int UNSIGNED_SHORT_MAX_VALUE = 65535;

private static final int UNSIGNED_SHORT_MIN_VALUE = 0;

public static void main(String args[]) {

Socket socket = null;

BufferedReader reader = null;

try {

reader = new BufferedReader(new InputStreamReader(System.in));

socket = new Socket(SERVER_ADDRESS, SERVER_PORT);

int a = readUnsignedShort("a = ", reader);

int b = readUnsignedShort("b = ", reader);

writeIntegersToSocket(a, b, socket);

readIntegersSumFromSocket(socket);

} catch (IOException e) {

System.err.println("Cautgh exception " + e.getMessage());

} finally {

closeStreams(socket,reader);

}

private static void readIntegersSumFromSocket(Socket c) throws IOException {

DataInputStream socketIn = new DataInputStream(c.getInputStream());

int s = socketIn.readUnsignedShort();

System.out.println("s = " + s);

}

private static void writeIntegersToSocket(int a, int b, Socket c) throws IOException {

DataOutputStream socketOut = new DataOutputStream(c.getOutputStream());

socketOut.writeShort(a);

socketOut.writeShort(b);

socketOut.flush();

}

private static int readUnsignedShort(String message, BufferedReader reader) throws IOException {

int unsignedShortNumber = 0;

System.out.print(message);

try {

unsignedShortNumber = Integer.parseInt(reader.readLine());

if (unsignedShortNumber < UNSIGNED_SHORT_MIN_VALUE || unsignedShortNumber > UNSIGNED_SHORT_MAX_VALUE) {

throw new IllegalArgumentException("The given number must be unsigned short [0..65535]!");

}

} catch (NumberFormatException e) {

System.err.println("The given input is not an integer!");

}

return unsignedShortNumber;

}

private static void closeStreams(Socket socket, BufferedReader reader) {

if (socket != null) {

try {

socket.close();

} catch (IOException e) {

System.err.println("Could not close socket!");

}

if (reader != null) {

try {

reader.close();

} catch (IOException e) {

System.err.println("Could not close reader!");

}