How you can do Inter course of communication in Java? Instance Tutorial

Whats up guys, prior to now, I’ve proven you how to do inter-thread communication in Java utilizing wait-notify, and in the present day, I’ll train you methods to do inter-process communication in Java. There are lots of methods to do inter-process communication in Java, you should utilize Sockets, each TCP and UDP, you should utilize RMI (Distant Methodology Invocation), you should utilize internet companies, or you should utilize memory-mapped file. The socket is the commonest manner of reaching inter-process communication if two processes are in two totally different hosts and linked by way of a community. RMI and WebService will also be used for related functions, however the final one, inter-process communication utilizing memory-mapped recordsdata, is especially helpful if you’re speaking with different processes in the identical host, sharing the identical reminiscence and file system.

You may use a memory-mapped file to speak to a different Java course of or C/C++ course of as a result of they share the identical reminiscence. It’s also the quickest solution to share knowledge between two processes, extra fast than utilizing loopback sockets.

In a multi-core system, two processes can run on separate cores, and if you’re actually doing quick knowledge sharing, you additionally want a mechanism to inform JVM that it is time to flush CPU cache, utilizing a static risky variable is a wonderful solution to say that, alternatively you should utilize Thread.sleep() to offer a while to JVM to replace CPU cache.

Btw, if you’re critical about constructing a high-performance Java utility then I additionally advocate you try these Java Multithreading and Concurrency programs which is a superb course for skilled Java programmers. You’ll be taught suggestions and tips to create extremely concurrent and quick Java purposes.

How you can do Interprocess communication in Java? Instance

Here’s a code instance of two processes speaking with one another utilizing a Reminiscence Mapped file in Java. 

Course of 1 which is producing knowledge :

import java.io.IOException;
import java.io.RandomAccessFile;
import java.nio.MappedByteBuffer;
import java.nio.channels.FileChannel;



public class Producer {

    public static void essential(String args[]) throws IOException, InterruptedException {

        RandomAccessFile rd = new RandomAccessFile("C:/temp/mapped.txt", "rw");

        FileChannel fc = rd.getChannel();
        MappedByteBuffer mem = fc.map(FileChannel.MapMode.READ_WRITE, 0, 1000);

        strive {
            Thread.sleep(10000);
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
     
        for(int i=1; i            mem.put( (byte) i);
            System.out.println("Course of 1 : " + (byte)i );
            Thread.sleep(1); 
        }
    }
}

Output
Course of 1: 1
Course of 1: 2
Course of 1 : 3
Course of 1: 4
Course of 1: 5
Course of 1: 6
Course of 1: 7
Course of 1: 8
Course of 1: 9

And here’s a diagram that reveals how this entire factor is working collectively:

Course of 2, which is consuming knowledge

import java.io.IOException;
import java.io.RandomAccessFile;
import java.nio.MappedByteBuffer;
import java.nio.channels.FileChannel;



public class Client {

    public static void essential(String args[]) throws IOException {

        RandomAccessFile rd = new RandomAccessFile("C:/temp/mapped.txt", "r");

        FileChannel fc = rd.getChannel();
        MappedByteBuffer mem = fc.map(FileChannel.MapMode.READ_ONLY, 0, 1000);
     
        strive {
            Thread.sleep(10000);
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
     
     
        int worth = mem.get();
        whereas(worth != 0){
            System.out.println("Course of 2 : " + worth);
            worth = mem.get();
        }
    }
}


Output
Course of 2: 1
Course of 2: 2
Course of 2 : 3
Course of 2: 4
Course of 2: 5
Course of 2: 6
Course of 2: 7
Course of 2: 8
Course of 2: 9