/*
 * Demonstration Java program for the PSPSOCK ISeries Sockets development
 * framework. Web site: http://www.prosperosoftware.co.uk
 *
 * This is a sockets client program that communicates with a sockets-based
 * service running on an IBM ISeries computer. In this case, the service number
 * is 1. This identifies a service provided as a default by our company when
 * you install the PSPSOCK framework on your ISeries. This service simply echoes
 * the data sent by this - or any other - client program back to the client program.
 * You will need to refer to documentation on our Web site and in the PSPSOCK
 * library you installed on your ISeries to understand what this client Java
 * program should do. That service is listening on port 12345 (unless it has
 * been reconfigured on ISeries to listen on a different port).
 */


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

public class PSPS00001C {
  /* Default static constructor with parameters. */
  public static void main(String[] args) {
    new PSPS00001C(args);
  }
  public PSPS00001C(String[] args) {
    // This demonstration client runs on a PC attached to the ISeries. That ISeries
    // in our case has IP address below. That address can be pinged from the PC.
    // You will have to change the address to match your own ISeries.
    String host = "192.168.20.20";
    // The ISeries service is listening on port 12345. Run the PSPSOCK command to
    // see the configuration for this service.
    int port = 12345;
    Socket s = null;
    PrintWriter out = null;
    BufferedReader in = null;
    char output[] = new char[7];
    String read = null;
    int readLen = 0;
    // Step 1: Connect to the server.
    try {
      s = new Socket(host,port);
    }
    catch (Exception e) {
      System.err.println("Socket() failed with " + e.getMessage());
      System.exit(1);
    }
    // If we get this far than the client Java program has successfully connected
    // with the ISeries service. If client read/write operations below fail, then
    // errors may be logged by the service on the ISeries. Run the PSPSOCK command
    // to see logged error messages for the service.
    try {
      out = new PrintWriter(s.getOutputStream(), true);
    }
    catch (Exception e) {
      System.err.println("PrintWriter() failed with " + e.getMessage());
      System.exit(1);
    }
    try {
      in = new BufferedReader(new InputStreamReader(s.getInputStream()));
    }
    catch (Exception e) {
      System.err.println("BufferedReader() failed with " + e.getMessage());
      System.exit(1);
    }
    // Step 2: Write data to the server.
    // The protocol for this service requires 1) a 4 byte integer value indicating
    // the number of characters that follow on, 2) the actual characters. For this
    // demo, send 3 characters "ABC".
    try {
      output[0] = 0X00;
      output[1] = 0X00;
      output[2] = 0X00;
      output[3] = 0X03; // 3 bytes follow this byte
      output[4] = 'A'; // Hexadecimal 41 in ASCII
      output[5] = 'B'; // Hexadecimal 42 in ASCII
      output[6] = 'C'; // Hexadecimal 43 in ASCII
      out.write(output,0,7);
      out.flush();
    }
    catch (Exception e) {
      System.err.println("write() failed with " + e.getMessage());
      System.exit(1);
    }
    String write = new String(output);
    int writeLen = write.length();
    System.out.println("Sent to server = " + writeLen + " characters:");
    auditBytes(write,writeLen);
    // Step 3: Read data response back from the server.
    try {
      read = in.readLine();
    }
    catch (Exception e) {
      System.err.println("readLine() failed with " + e.getMessage());
      System.exit(1);
    }
    readLen = read.length();
    System.out.println("Returned from server = " + readLen + " characters:");
    auditBytes(read,readLen);
    // Step 4: Close all open connections.
    try {
      out.close();
      in.close();
      s.close();
    }
    catch (Exception e) {
      System.err.println("close() failed with " + e.getMessage());
      System.exit(1);
    }
  }
  void auditBytes(String dta, int dtaLen) {
    for (int x = 0; x < dtaLen; x++) {
      System.out.println("Byte " + x + " = " + dta.charAt(x) + " hex " + Integer.toHexString(dta.charAt(x)));
    }
  }
}