Java Thread Test22 parallel work example

// Ttest22.java
// creates threads from the class Thread22.java
// demonstrates inter-thread communication (message passing)

// compile this file with the command "javac Ttest22.java"
// your path must include the bin directory of the jdk

// run the program with "java Ttest22"
// on some systems

/********************************************************************************/
/* class Ttest22: examples to build on toward bucket sort                       */
/********************************************************************************/
public class Ttest22 {
	public static int sharedarray[] = new int[4];
	public static Thread22 tptr[] = new Thread22[4];
/********************************************************************************/
        public static void main(String argv[]) {
		  int i;
		  initshared();
                  printarray();

		  for (i=0;i<2;i++) {
		      tptr[i] = new Thread22(i,4,2);
		  }

                  System.out.println("Ttest22: made threads");
		  for (i=0;i<2;i++) {
		      tptr[i].start();
		  }

                  System.out.println("Ttest22: started threads");

		  //Next, wait for all threads to finish - join()
		  try {
		     for (i=0;i<2;i++) {
			tptr[i].join();
		     }
		  } catch(InterruptedException e) {}
		  printarray();
		  tptr[0].sayHello();
        }
/********************************************************************************/
/* method passcall(int): testing message passing                                */
/********************************************************************************/
	public static void passcall(int id) {
		  tptr[id].sayHello();
	}
/********************************************************************************/
/* method initshared(): initializes an example array                            */
/********************************************************************************/
	private static void initshared() {
		  sharedarray[0]=4;
		  sharedarray[1]=1;
		  sharedarray[2]=3;
		  sharedarray[3]=2;
	}
/********************************************************************************/
/* method printarray(): note that System.out is not thread safe                 */
/********************************************************************************/
	private static void printarray() {
		  int i;
		  System.out.print("Main: shared array= ");
		  for (i=0;i<4;i++) {
		      System.out.print(" " + sharedarray[i]);
                  }
		  System.out.println();
	}
	
}

//$$$$$$$$$$$$$$$$$$$$$ second file $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$

// this is file Thread22.java
// compile with "javac Thread22.java"

//demonstrates interthread communcation

/********************************************************************************/
/* class Thread22: example parallel threads, toward parallel bucket sort        */
/********************************************************************************/
class Thread22 extends Thread {
        private int subarray[]; 	//copy for this thread
	private int myid;		// thread ID
	private int numint;		//number of integers in big array
	private int numt;		//number of threads working
	private int numtosort;		//number of integers in my array
	private int startposition;	//pos in big shared array
        private int i;			//counting variable

/********************************************************************************/
/* method Thread22(int, int, int): thread constructor                           */
/********************************************************************************/
	public Thread22(int me, int numitems, int numthreads) {
	   System.out.println("Hi from thread " + getName());
	   myid = me;
	   numint = numitems;
	   numt = numthreads;
	}

/********************************************************************************/
/* method run(): the thread code                                                */
/********************************************************************************/	
        public void run() {
	      numtosort = numint/numt;
	      startposition = 0 + myid*numtosort;
              subarray = new int [numtosort];
              System.out.println(getName() + "  myid=" + myid);
	      for (i=0;i subarray[1]) {
		temp = subarray[0];
		subarray[0] = subarray[1];
		subarray[1] = temp;
	     }
	}
}