Monday, 13 July 2015

Java Programs[Important]

  1.   WRITE A JAVA PROGRAM that creates 3 threads by extending Thread class. First thread displays “Good Morning” every 1 sec, the second thread displays “Hello” every 2 seconds and the third displays “Welcome” every 3 seconds. (Repeat the same by implementing Runnable)
  2.  
  3. Program :
  4.  
  5. // Using Thread class 
  6. class One extends Thread 
  7. { 
  8. public void run()
  9.  { 
  10. for ( ; ; ) 
  11. { 
  12. try
  13. { 
  14. sleep(1000); 
  15. }
  16. catch(InterruptedException e)
  17. {
  18. }
  19.  System.out.println("Good Morning"); 
  20. }
  21.  } 
  22. }
  23.  
  24. class Two extends Thread { public void run()   { 
  25.  

  27.  
  28. for ( ; ; )
  29.  { 
  30. try
  31. { 
  32. sleep(2000); 
  33. }
  34. catch(InterruptedException e)
  35. {
  36. } 
  37. System.out.println("Hello");
  38.  } 
  39. } 
  40. }
  41.  
  42. class Three extends Thread 
  43. { 
  44. public void run() 
  45. { 
  46. for ( ; ; )
  47.  { 
  48. try{ 
  49. sleep(3000);
  50.  }
  51. catch(InterruptedException e)
  52. {
  53. } 
  54. System.out.println("Welcome");
  55.  }
  56.  }
  57.  }
  58.  
  59. class MyThread { public static void main(String args[ ]) {   Page 111
  60.  

  62.  
  63. Thread t = new Thread();
  64.  One obj1=new One(); 
  65. Two obj2=new Two(); 
  66. Three obj3=new Three(); 
  67. Thread t1=new Thread(obj1);
  68.  Thread t2=new Thread(obj2); 
  69. Thread t3=new Thread(obj3);
  70.  
  71. t1.start(); try{ t.sleep(1000); }catch(InterruptedException e){} t2.start(); try{ t.sleep(2000); }catch(InterruptedException e){} t3.start(); try{ t.sleep(3000); }catch(InterruptedException e){}
  72.  
  73. }   

  75. }
  76.  
  77. // Using Runnable interface class One implements Runnable {
  78.  
  79. One( ) { new Thread(this, "One").start(); try{ Thread.sleep(1000); }catch(InterruptedException e){} }
  80.  
  81. public void run() { for ( ; ; ) { try{ Thread.sleep(1000); }catch(InterruptedException e){} System.out.println("Good Morning"); } } }

  83. class Two implements Runnable {
  84.  
  85. Two( ) { new Thread(this, "Two").start(); try{ Thread.sleep(2000); }catch(InterruptedException e){} }
  86.  
  87. public void run() for ( ; ; ) { try{
  88.  
  89. {
  90.  
  91. Thread.sleep(2000); }catch(InterruptedException e){} System.out.println("Hello"); } } }
  92.  
  93. class Three implements Runnable {
  94.  
  95. Three( ) { 
  96.  

  98.  
  99. new Thread(this, "Three").start(); try{ Thread.sleep(3000); }catch(InterruptedException e){} }
  100.  
  101. public void run() { for ( ; ; ) { try{ Thread.sleep(3000); }catch(InterruptedException e){} System.out.println("Welcome"); } } }
  102.  
  103. class MyThread { public static void main(String args[ ]) { One obj1=new One(); Two obj2=new Two(); Three obj3=new Three(); }  

  105.  
  106. }