Java Questions

 

Java Questions

Here we will see some core java interview questions only which is mostly asked in core java interviews. So let's starts

(1) What is java ?.

(2) List any five features of java ?.

(3) Tell me something about java history ?.

(4) What is bytcode in java ?.

(5) Is bytecode platform-independent or not ?.
(6) What is the meaning of 'WORA' in java ?.
(7) Which is the latest version of java and mention one feature of it ?.
(8) What is Java Virtual Machine(JVM) ?.
(9) JVM is a platform-independent or not ?.
(10) What is Java Runtime Environment(JRE) ?.
(11) What is Java Development Kit(JDK) ?.
(12) Difference between JVM, JRE, and JDK ?.
(13) Difference between JAVA and C++ ?.
(14) Which command or tool you will use to compile any java program?.
(15) Which command or tool you will use to execute any java program?.
(16) How many types of application you can create using java programming language ?.
(17) How many ways you can set the path of jdk(java) ?.
(18) What is a variable ?
(19) What is a data type in java ?
(20) How many types of Data Types in java ?.
(21) How many types of Variables in Java ?.
(22) What is a constructor in java ?.
(23) How many types of constructor in java ?
(24) What is type-casting in java ?
(25) List any five keyword of a java ?.
(26) What is polymorphism in java ?.
(27) How many types of polymorphism in java ?.
(28) What is static keyword in java ?.
(29) What is this keyword in java ?.
(30) What is super keyword in java ?.
(31) What is method overloading in java ?.
(32) What is method overriding in java ?.
(33) Difference between method overloading and overriding in java ?.
(34) Difference between constructor and method in java ?
(35) What is a Local variable in java ?.
(36) What is a instance variable in java ?.
(37) What is static variable in java ?.
(38) What is Final keyword in java ?.
(39) Can we apply final keyword with constructor in java ?.
(40) Can we override final method in java ?.
(41) What inheritance in java ?.
(42) How many types of inheritance in java ?.

(43) What is abstraction in java ?.
(44) What is access modifiers in java ?
(45) Can we overload main() method ?.
(46) Can we override main() method ?
(47) What is static binding and dynamic binding ?.
(48) What in class in java ?.
(49) What is interface in java ?
(50) Difference between class and interface in java ?.
(51) Similarities between class and interface ?.
(52) Why main() method is static in java ?.
(53) Can we inherit final class in java ?.
(54) Can we change the value of final variable ?.
(55) What is finally in java ?.
(56) What is finalize in java ?.
(57) Difference between final and finally and finalize in java ?
(58) What is a thread in java ?
(59) What is the name of parent or super class in java ?.
(60) How many ways we can create a thread in java ?.
(61) Can we apply private and protected modifiers with class ?.
(62) What is difference between List and Set interface in java ?.
(63) What is difference between ArrayList and Vector class in java ?.
(64) What is difference between HashSet and HashMap ?.
(65) How many primitive data types are there and what is the default value of each data types.
(66) what is an Array in java ?.
(67) How many types of an array in java ?.
(68) What is the advantage of an array ?
(69) Difference between Array and Collection in java ?.
(70) What is public, private, protected and default access modifiers ?.
(71) What is throw in java ?.
(72) What is throws in java ?
(73) Difference between throw and throws in java ?.
(74) What is a default method in java ?.
(75) How many ways we can create a thread and which one is the best in java ?.
(76) What is a try and catch?.
(77) Can we override static or private method ?.
(78) What is difference between Collection and Collections in java ?.
(79) What is comparable interface in java ?.
(80) What is comparator in java ?.
(81) Difference between comparable and comparator in java ?.
(82) What String in java ?.
(83) How to create object of String in java ?.
(84) What is string constant pool in java ?.
(85) List 10 methods of String class ?.
(86) What is System.out.println() in java ?.
(87) What object in java ?.
(88) What is Heap in java ?.
(89) What is JIT in java ?.
(90) What is package in java ?.
(91) What is synchronization in java ?
(92) What is static block in java ?.
(93) What is the default value of boolean ?.
(95) What is abstract method ?.
(96) Can we keep non abstract method in abstract class ?.
(97) Can we keep abstract method in non-abstract class ?.
(98) What is the default value of data member and method in interface ?.
(99) What is sleep(), join(), wait(), notify, notifyAll() in java ?.
(100) What is upcasting in java ?
(101) What is down-casting in java ?.