Program 3 Threads Demo

Write  a  Java  program  that  implements  a  multi-thread  application  that  has  three threads.  First  thread  generates  a  random  integer  for  every  1  second;  second thread  computes  the  square  of  the  number  and prints;  third  thread  will  print  the value of the cube of the number.

1  package edu.practice.java.threading; 2  3  public class NumberGenerator implements Runnable { 4  5          private Integer number; 6          private int count; 7          private int pendingConsumption = 0; 8  9          public NumberGenerator(int count) { 10                 this.count = count; 11         } 12  13         @Override 14         public void run() { 15                 for (int i = 0; i < this.count; i++) { 16                         try { 17                                 this.generate(); 18                                 Thread.sleep(1000); 19                         } catch (InterruptedException e) {} 20                 } 21         } 22  23         private synchronized void generate() { 24                 this.number = (int) (Math.random() * 20); 25                 this.pendingConsumption = 2; // Now I know how many consumers I have 26                 System.out.println("Generated number:" + this.number); 27                 this.notify(); 28         } 29  30         public synchronized Integer get() { 31                 while (this.pendingConsumption == 0) { 32                         try { 33                                 wait(); 34                         } catch (InterruptedException e) {} 35                 } 36                 this.pendingConsumption--; 37                 return this.number; 38         } 39  40 } 41  42 package edu.practice.java.threading; 43  44 public class Squarer implements Runnable { 45          46         private NumberGenerator numberGenerator; 47         private int count; 48  49         public Squarer(NumberGenerator numberGenerator, int count) { 50                 this.count = count; 51                 this.numberGenerator = numberGenerator; 52         } 53  54         @Override 55         public void run() { 56                 for (int i = 0; i < count; i++) { 57                         try { 58                                 Integer number = this.numberGenerator.get(); 59                                 System.out.println("Square of " + number + " is " + (number * number)); 60                                 Thread.sleep(1000); 61                         } catch (InterruptedException e) {} 62                 } 63         } 64  65 } 66  67 package edu.practice.java.threading; 68  69 public class Cuber implements Runnable { 70  71         private NumberGenerator numberGenerator; 72         private int count; 73  74         public Cuber(NumberGenerator numberGenerator, int count) { 75                 this.count = count; 76                 this.numberGenerator = numberGenerator; 77         } 78  79         @Override 80         public void run() { 81                 for (int i = 0; i < count; i++) { 82                         try { 83                                 Integer number = this.numberGenerator.get(); 84                                 System.out.println("Cube of " + number + " is " + (number * number * number)); 85                                 Thread.sleep(1000); 86                         } catch (Exception e) {} 87                 } 88         } 89  90 } 91  92 package edu.practice.java.threading; 93  94 public class ThreeMusketeers { 95  96         public static void main(String[] args) { 97                 System.out.println("Let's play"); 98                 final int count = 5; 99                 NumberGenerator numberGenerator = new NumberGenerator(count); 100                Thread generator = new Thread(numberGenerator); 101                Thread squarer = new Thread(new Squarer(numberGenerator, count)); 102                Thread cuber = new Thread(new Cuber(numberGenerator, count)); 103                 104                generator.start(); 105                squarer.start(); 106                cuber.start(); 107        } 108 109}

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OUTPUT:

Let's play

Generated number:9

Cube of 9 is 729

Square of 9 is 81

Generated number:12

Cube of 12 is 1728

Square of 12 is 144

Generated number:15

Cube of 15 is 3375

Generated number:8

Square of 8 is 64

Cube of 15 is 3375

Generated number:14

Cube of 14 is 2744

Square of 14 is 196

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