JAVA

1. Java-overview 2. Features of Java 3. History of Java 4. HW SW Req for Java SE 7 5. Java Environment Setup 6. Basic Requirement 7. Comments 8. My First Program in Java 9. Line Break 10. Escape Sequences 11. Literals in Java 12. Identifiers in Java 13. Variables in Java 14. Data-Types in Java 15. Declare Variables 16. Reserved Key Words 17. printf() 18. Chained & Embedded state 19. Prog.to print sum of 2 nos 20. Scanner class 21. Prg.to print sum & average 22. Area & Perimeter of Rectangle 23. Area Circumference of Circle 24. Prg.for Simple Calculator 25. Operatos in Java 26. Ex. Of Operators 27. Swap two numbers 28. Hierarchy of Operators 29. if( ) statement 30. Prg.to check +ve,-ve or zero 31. if..else statement 32. Prg.to check Odd or Even 33. Prg.to print larger of 2 nos 34. Prg.to print largest of 3 nos 35. Prg.to check divisibility 36. Prg.to check print range 37. for. . . loop statement 38. prg.to print series of nos 39. Prg.to check divisibility 40. prg.to print sum of nos 41. Prg.to print Pyramid 42. prg.for Factorial 43. prg.to fill screen 44. prg.for largest/smallest no 45. prg.to print reverse no 46. prg.to add each digit 47. prg.for sum of series 48. prg.for fibonacci series 49. prg.to check Prime nos 50. prg. Prime no from 1 to 100 51. prg.Specified Prime nos 52. while( ) statement 53. do. . While statement 54. break & continue statement 55. switch case statement 56. Array in Java 57. print reverse order using array 58. Ascending/Descending order 59. prg.to search no in Array 60. Multidimensional Array 61. String in Java 62. String with spaces 63. prg.to print string in reverse 64. prg. to count A,E,I,O,U vowel 65. User defined methods 66. Methods program example 67. General Purpose Programs 68. Loan & EMI calculation prg. 69. Table print prg. 70. Leap year program 71. lower to UPPER case prg. 72. Age Distribution prg. 73. Bank note calculation prg. 74. Simple Interest prg. 75. Compound Interest prg. 76. Simple Depreciation prg. 77. Reducing bal.Depreciation prg. 78. Marksheet prg. 79. Income Tax prg. 80. Time calculator prg. 81. Distance converter prg. 82. Volume Air Calculation prg. 83. Time to fill Water Tank prg. 84. Salary Calculation prg. 85. Total Sale Calculation prg. 86. Male/Female percentage prg. 87. Library Rent prg. 88. Office Expance prg. 89. Total Salary Calculation prg. 90. Profit or Loss prg. 91. Total Profit/Loss prg. 92. Palindrome program 93. Java Interview Part1 94. Java Interview Part2 95. Java Interview Part3 96. Java Interview Part4 97. Java Interview Part5 98. Java Interview Part6 99. Java Interview Part7 100. Java Interview Part8 101. Java Interview Part9 102. Java Interview Part10 103. Java Interview Part11
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JAVA Interview Questions and Answers Part 8

 

71. I don't want my class to be inherited by any other class. What should i do?

  • You should declared your class as final. But you can't define your class as final, if it is an abstract class. A class declared as final can't be extended by any other class.

 

72. Can you give few examples of final classes defined in Java API?

  • java.lang.String, java.lang.Math are final classes.

 

73. How is final different from finally and finalize()?

  • final is a modifier which can be applied to a class or a method or a variable. final class can't be inherited, final method can't be overridden and final variable can't be changed. finally is an exception handling code section which gets executed whether an exception is raised or not by the try block code segment.

  • finalize() is a method of Object class which will be executed by the JVM just before garbage collecting object to give a final chance for resource releasing activity.

 

74. Can a class be declared as static?

  • No a class cannot be defined as static. Only a method, a variable or a block of code can be declared as static.

 

75. When will you define a method as static?

  • When a method needs to be accessed even before the creation of the object of the class then we should declare the method as static.

 

76. What are the restriction imposed on a static method or a static block of code?

  • A static method should not refer to instance variables without creating an instance and cannot use "this" operator to refer the instance.

 

77. I want to print "Hello" even before main() is executed. How will you acheive that?

  • Print the statement inside a static block of code. Static blocks get executed when the class gets loaded into the memory and even before the creation of an object. Hence it will be executed before the main() method. And it will be executed only once.

 

78. What is the importance of static variable?

  • static variables are class level variables where all objects of the class refer to the same variable. If one object changes the value then the change gets reflected in all the objects.

 

79. Can we declare a static variable inside a method?

  • static varaibles are class level variables and they can't be declared inside a method. If declared, the class will not compile.

 

80. What is an Abstract Class and what is it's purpose?

  • A Class which doesn't provide complete implementation is defined as an abstract class. Abstract classes enforce abstraction.

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