Question

THE SOLUTION MUST BE SUBMITTED AS 3 JAVA FILES

Consider the threads hierarchy below: T2 T1 T3 T1 will ask the user to enter an array of size N and will fill the array with student grades. T1 will then send the array to threads T2 and T3. T2 will compute the maximum grade of passed students. T3 will compute the maximum grade of failed students. T1 will print the maximum and minimum grades returned by threads T2 and T3. Note: A student passes an exam if his/her grade is greater than or equal to 60. T1 is the main thread.

Answer 1

//Main.java

package t1;

import java.util.Scanner; //for taking inputs
import java.util.concurrent.ExecutorService; //for making thread pools
import java.util.concurrent.Executors;
import java.util.concurrent.Future; //to call the threads


public class Main {

public static void main(String args[]) throws Exception {
   Scanner s = new Scanner(System.in);
   int n;
   int[] array = new int[100];
   System.out.print("\nEnter the number of grades: ");
   n = s.nextInt(); //taking input for number of grades
   System.out.print("\nEnter the grades: ");
   for(int i = 0; i<n ; i++) { //taking input for grades
       array[i] = s.nextInt();
   }
   ExecutorService service = Executors.newFixedThreadPool(1); //creating a pool of threads
   Future<Integer> m = service.submit(new MainThread(array, n)); //calling t1 thread calls constructor then call method
   service.shutdown(); //shutting down Executor Service
}
}

//MainThread.java

package t1;

import java.util.concurrent.Callable;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.Future;


public class MainThread implements Callable<Integer>{
   int[] array;
   int n;
public MainThread(int[] array,int n) {
   this.array= array; //we set the array in constructor
   this.n = n; //set the number of grades
}
public void print() { //print function to see contents of array
   System.out.println("\nIn MainThread");
   for(int i = 0; i<n ; i++) {
       System.out.print("\t"+array[i]);
   }
  
}
@Override
public Integer call() throws Exception{
   ExecutorService service = Executors.newFixedThreadPool(2); //creating a pool of 2 threads
   Future<Integer> max_pass = service.submit(new t2Thread(array, n)); //sending to t2 thread
   Future<Integer> max_fail = service.submit(new t3Thread(array, n)); //sending to t3 thread
   System.out.print("\n\nMax grade of Passed students: "+max_pass.get()); //value is received from t2.call() function
   System.out.print("\nMax grade of Failed students: "+max_fail.get()); //value is received from t3.call() function
   service.shutdown();
   return 0;
}
}

//t2Thread.java

package t1;
import java.util.concurrent.Callable;
public class t2Thread implements Callable<Integer>{
   int[] array = new int[100];
   int n;
  
   t2Thread(int[] array,int n) { //constructor to assign values to array and n
       this.array = array;
       this.n = n;
      
   }
   public void print() { //print function to see the contents of the array
   System.out.println("\nIn t2");
   for(int i = 0; i<n ; i++) {
       System.out.print("\t"+array[i]);
   }
  
}
   @Override
   public Integer call() throws Exception {
       int max_pass = -1;
       //print();
       for(int i = 0; i< n; i++) { //finding out the max grade of passed student
           if(max_pass < array[i] && array[i] >= 60) {
               max_pass = array[i];
           }
       }
       return max_pass; //returning the value
   }
      
}

//t3Thread.java

package t1;
import java.util.concurrent.Callable;

public class t3Thread implements Callable<Integer>{
   int[] array = new int[100];
   int n;
  
   t3Thread(int[] array,int n) {//constructor to assign values to array and n
       this.array = array;
       this.n = n;
      
   }
   public void print() { //print function to see the contents of the array
   System.out.println("\nIn t3");
   for(int i = 0; i<n ; i++) {
       System.out.print("\t"+array[i]);
   }
  
}
   @Override
   public Integer call() throws Exception {
       int max_fail = -1;
       //print();
       for(int i = 0; i< n; i++) { //finding out the max grade of failed student
           if(max_fail < array[i] && array[i] < 60) {
               max_fail = array[i];
           }
       }
       return max_fail;
   }

}

Main.java

*MainThread.java t2Thread.java Main.java X t3Thread.java 1 package t1; 2 30 import java.util.Scanner; //for taking inputs 4 import java.util.concurrent. ExecutorService; //for making thread pools 5 import java.util.concurrent. Executors; 6 import java.util.concurrent. Future; //to call the threads 7 8 9 public class Main { 10 110 public static void main(String args[]) throws Exception { 12 Scanner s = new Scanner(System.in); 13 14 int[] array = new int[100]; 15 System.out.print("\nEnter the number of grades: "); 16 n = s.nextInt(); //taking input for number of grades 17 System.out.print("\nEnter the grades: "); 18 for(int i = 0; i<n; i++) { //taking input for grades 19 array[i] = s.nextInt(); 20 21 ExecutorService service = Executors.newFixedThreadPool(1); //creating a pool of threads 22 Future<Integer> m = service. submit(new MainThread(array, n)); //calling ti thread calls constructor then call method 23 service. shutdown(); //shutting down Executor Service 24 } int n; } 25 }


MainThread.java
*MainThread.java X t2Thread.java Main.java t3Thread.java 1 package t1; 2 3- import java.util.concurrent.Callable; 4 import java.util.concurrent. ExecutorService; 5 import java.util.concurrent. Executors; 6 import java.util.concurrent. Future; } } 8 public class MainThread implements Callable<Integer>{ 9 int[] array; 10 int n; 11 public MainThread(int[] array, int n) { 12 this.array= array; //we set the array in constructor 13 this.n = n; // set the number of grades 14 150 public void print() { //print function to see contents of array 16 System.out.println("\nIn MainThread"); 17 for(int i = 0; i<n; i++) { 18 System.out.print("\t"+array[i]); 19 20 21 22 @Override 23 public Integer cali() throws Exception{ 24 ExecutorService service = Executors.newFixedThreadPool(2); //creating a pool of 2 threads 25 Future<Integer> max_pass = service. submit(new t2Thread(array, n)); //sending to t2 thread Future<Integer> max_fail = service.submit(new t3Thread(array, n)); //sending to t3 thread 27 System.out.print("\n\nMax grade of Passed students: "+max_pass.get()); //value is received from t2.call() function 28 System.out.print("\nMax grade of Failed students: "+max_fail.get()); //value is received from t3.call() function service. shutdown(); 30 return 0; 31 } 32 } } 26 29

t2Thread.java

int n; ها . *MainThread.java t2Thread.java * Main.java t3Thread.java 1 package t1; 2 import java.util.concurrent.Callable; 3 public class t2Thread implements Callable<Integer>{ 4 int[] array = new int[100]; 5 6 70 t2Thread(int[] array, int n) { //constructor to assign values to array and n 8 this.array = array; 9 this.n = n; 10 11 12 public void print() { //print function to see the contents of the array 13 System.out.println("\nIn t2"); 14 for(int i = 0; i<n; i++) { 15 System.out.print("\t"+array[i]); 16 17 18 190 @Override -20 public Integer call() throws Exception { 21 int max_pass = -1; 22 //print) 23 for(int i = 0; i< n; i++) { //finding out the max grade of passed student 24 if(max_pass < array[i] && array[i] >= 60) { 25 max_pass = array[i]; 26 27 28 return max_pass; //returning the value 29 30 31 } } } } }

t3Thread.java

t3Thread.java X *MainThread.java t2Thread.java Main.java 1 package t1; 2 import java.util.concurrent.Callable; 3 9 } 4 public class t3Thread implements Callable<Integer>{ 5 int[] array = new int[100]; 6 int n; 7 80 t3Thread(int[] array, int n) {//constructor to assign values to array and n this.array = array; 10 this.n = n; 11 12 13e public void print() { //print function to see the contents of the array 14 System.out.println("\nIn t3"); 15 for(int i = 0; i<n; i++) { 16 System.out.print("\t"+array[i]); 17 18 19 } 20 @Override 421 public Integer call() throws Exception { 22 int max_fail = -1; 23 //printe 24 for(int i = 0; i<n; i++) { //finding out the max grade of failed student 25 if(max_fail < array[i] && array[i] < 60) { 26 max_fail = array[i]; 27 28 29 return max_fail; 30 31 32 } } } w

OUTPUT

t2Thread.java Main.java Dt3Thread.java * *MainThread.java 1 package t1; Problems @ Javadoc Declaration Console X <terminated> Main [Java Application] C:\Program Files\ava\jre 1.8.0_251\bin\javaw.exe (30-Jul-2020, 1:28:11 am Enter the number of grades: 5 Enter the grades: 90 80 70 60 50 Max grade of Passed students: 90 Max grade of Failed students: 50