Solved

java read vs readline

Posted on 2009-07-13
2
330 Views
Last Modified: 2013-11-23
First let me admit that I barely know java enough to be dangerous.  

I'd like to modify the code below (in the function run) so that when it receives a message, it prints it to the console, but I don't want it to print a CR LF.

I get some compiler warnings about depreciated functions, so fee free to update the code where it makes sense to do so:

An added bonus would be to make the program exit gracefully if the user hits ctrl-c
import java.io.*;
import java.net.*;
import java.security.*;
 
/**
 * Title:        Sample Server
 * Description:  This utility will accept input from a socket, posting back to the socket before closing the link.
 * It is intended as a template for coders to base servers on. Please report bugs to brad at kieser.net
 * Copyright:    Copyright (c) 2002
 * Company:      Kieser.net
 * @author B. Kieser
 * @version 1.0
 */
 
public class sample_server {
 
  private static int port=12310, maxConnections=0;
  // Listen for incoming connections and handle them
  public static void main(String[] args) {
    int i=0;
 
    try{
      ServerSocket listener = new ServerSocket(port);
      Socket server;
 
      while((i++ < maxConnections) || (maxConnections == 0)){
        doComms connection;
 
        server = listener.accept();
        doComms conn_c= new doComms(server);
        Thread t = new Thread(conn_c);
        t.start();
      }
    } catch (IOException ioe) {
      System.out.println("IOException on socket listen: " + ioe);
      ioe.printStackTrace();
    }
  }
 
}
 
class doComms implements Runnable {
    private Socket server;
    private String line,input;
 
    doComms(Socket server) {
      this.server=server;
    }
 
    public void run () {
 
      input="";
 
      try {
        // Get input from the client
        DataInputStream in = new DataInputStream (server.getInputStream());
        PrintStream out = new PrintStream(server.getOutputStream());
 
        while((line = in.readLine()) != null) {
          input=input + line;
        }
 
        // Now write to the client
 
        System.out.print("> " + input);
 
        server.close();
      } catch (IOException ioe) {
        System.out.println("IOException on socket listen: " + ioe);
        ioe.printStackTrace();
      }
    }
}

Open in new window

0
Comment
Question by:MrGone06095
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
2 Comments
 
LVL 86

Accepted Solution

by:
CEHJ earned 250 total points
ID: 24844590
Try the following:
import java.io.*;
import java.net.*;
import java.security.*;
 
/**
 * Title:        Sample Server
 * Description:  This utility will accept input from a socket, posting back to the socket before closing the link.
 * It is intended as a template for coders to base servers on. Please report bugs to brad at kieser.net
 * Copyright:    Copyright (c) 2002
 * Company:      Kieser.net
 * @author B. Kieser
 * @version 1.0
 */
 
public class sample_server {
 
  private static int port=12310, maxConnections=0;
  // Listen for incoming connections and handle them
  public static void main(String[] args) {
    int i=0;
 
    try{
      ServerSocket listener = new ServerSocket(port);
      Socket server;
 
      while((i++ < maxConnections) || (maxConnections == 0)){
        doComms connection;
 
        server = listener.accept();
        doComms conn_c= new doComms(server);
        Thread t = new Thread(conn_c);
        t.start();
      }
    } catch (IOException ioe) {
      System.out.println("IOException on socket listen: " + ioe);
      ioe.printStackTrace();
    }
  }
 
}
 
class doComms implements Runnable {
    private Socket server;
    private String line,input;
 
    doComms(Socket server) {
      this.server=server;
    }
 
    public void run () {
 
      input="";
 
      try {
        // Get input from the client
        BufferedReader in = new BufferedReader(new InputStreamReader(server.getInputStream()));
        PrintWriter out = new PrintWriter(server.getOutputStream(), true);
 
        while((line = in.readLine()) != null) {
          input=input + line;
        }
 
        // Now write to the client
 
        out.println("> " + input);
 
        server.close();
      } catch (IOException ioe) {
        System.out.println("IOException on socket listen: " + ioe);
        ioe.printStackTrace();
      }
    }
}

Open in new window

0
 
LVL 92

Assisted Solution

by:objects
objects earned 250 total points
ID: 24844982
> An added bonus would be to make the program exit gracefully if the user hits ctrl-c

try using a shutdown hook

http://helpdesk.objects.com.au/java/how-can-i-get-some-code-run-when-my-application-shuts-down
0

Featured Post

Independent Software Vendors: We Want Your Opinion

We value your feedback.

Take our survey and automatically be enter to win anyone of the following:
Yeti Cooler, Amazon eGift Card, and Movie eGift Card!

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

After being asked a question last year, I went into one of my moods where I did some research and code just for the fun and learning of it all.  Subsequently, from this journey, I put together this article on "Range Searching Using Visual Basic.NET …
Java functions are among the best things for programmers to work with as Java sites can be very easy to read and prepare. Java especially simplifies many processes in the coding industry as it helps integrate many forms of technology and different d…
Viewers will learn about the different types of variables in Java and how to declare them. Decide the type of variable desired: Put the keyword corresponding to the type of variable in front of the variable name: Use the equal sign to assign a v…
This tutorial explains how to use the VisualVM tool for the Java platform application. This video goes into detail on the Threads, Sampler, and Profiler tabs.

634 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question