10 Interesting Core Java Interview Coding Questions and Answers

Posted by: Instanceofjava Posted date: May 08, 2015 / comment : 10 ,

1. What is the output of following program?


  1. package com.instanceofjava;
  2.  
  3. public class B{
  4.  
  5.   B b= new B();
  6.  
  7.  public int show(){
  8.       return (true ? null : 0);
  9.  }
  10.  
  11.  public static void main(String[] args)  {
  12.  
  13.         B b= new B();
  14.         b.show();
  15.     }
  16.  
  17. }




Exaplanation:

  • Whenever we create the object of any class constructor will be called first and memory allocated for all non static variables
  • Here  B b= new B(); variable is object and assigned to new object of same class
  • B b= new B(); statement leads to recursive execution of constructor will create infinite objects so at run time an exception will be raised
  • Exception in thread "main" java.lang.StackOverflowError
  • The common cause for a stack overflow exception  is a bad recursive call. Typically this is caused when your recursive functions doesn't have the correct termination condition

2. What is the output of following program?


  1. package com.instanceofjava;
  2.  
  3. public class A{

  5.  
  6.  public static void show(){
  7.  
  8.         System.out.println("Static method called");
  9.  }
  10.  
  11.  public static void main(String[] args)  {
  12.  
  13.         A obj=null;
  14.         obj.show();
  15.  
  16.     }
  17.  
  18. }



Exaplanation:

  • We can call static methods using reference variable which is pointing to null because static methods are class level so we can either call using class name and reference variable which is pointing to null.


3. What is the output of following program?


  1. package com.instanceofjava;
  2.  
  3. public class A{

  5.  
  6.  static int a = 1111;
  7.  static
  8.  {
  9.         a = a-- - --a;
  10.  }
  11.     
  12. {
  13.         a = a++ + ++a;
  14.  }
  15.  
  16.  public static void main(String[] args)  {
  17.  
  18.        System.out.println(a);
  19.  
  20.     }
  21.  
  22. }




Explanation:

Top 10 Increment and decrement  operators interview Questions

4. What is the output of following program?


  1. package com.instanceofjava;
  2.  
  3. public class A{

  5.  
  6.  int GetValue()
  7.  {
  8.         return (true ? null : 0);
  9.  }
  10.  
  11.  public static void main(String[] args)  {
  12.  
  13.    A obj= new A();

  15.       obj.GetValue();
  16.  
  17.     }
  18.  
  19. }




5. What is the output of following program?


  1. package com.instanceofjava;
  2.  
  3. public class A{

  5.   
  6.  public static void main(String[] args)  {
  7.  
  8.    Integer i1 = 128;
  9.  
  10.    Integer i2 = 128;
  11.  
  12.      System.out.println(i1 == i2);
  13.  
  14.    Integer i3 = 127;
  15.    Integer i4 = 127;
  16.  
  17.       System.out.println(i3 == i4);
  18.  
  19.     }
  20.  
  21. }




6. What is the output of following program?


  1. package com.instanceofjava;
  2. class A
  3. {
  4.     
  5. void method(int i)
  6. {
  7.  
  8.  }
  9.  
  10.     }
  11.  
  12.  class B extends A
  13.  {
  14.  
  15. @Override
  16. void method(Integer i)
  17.  {
  18.  
  19.  }
  20.           


  23. }



7. Which line will throw compile time error? 8 or 9?


  1. package com.instanceofjava;
  2. class A
  3. {
  4.     
  5. public static void main(String [] args)
  6. {
  7.  
  8.   Integer i = new Integer(null);
  9.   String s = new String(null);
  10.  
  11.  }
  12.  
  13. }



8.What is the output of following program?


  1. package com.instanceofjava;
  2. class A
  3. {
  4.     
  5. public static void main(String [] args)
  6. {
  7.  
  8.   String s = "ONE"+3+2+"TWO"+"THREE"+5+4+"FOUR"+"FIVE"+5;
  9.   System.out.println(s);
  10.  
  11.  }
  12.  
  13. }



9.What is the output of following program?


  1. package com.instanceofjava;
  2. class A
  3. {
  4.  
  5. static int method1(int i)
  6. {
  7. return method2(i *= 11);
  8. }
  9.  
  10.  static int method2(int i)
  11. {
  12.   return method3(i /= 11);
  13. }
  14.  
  15.  static int method3(int i)
  16. {
  17.  return method4(i -= 11);
  18. }
  19.  
  20.  static int method4(int i)
  21. {
  22.   return i += 11;
  23. }
        
  24. public static void main(String [] args)
  25. {
  26.  
  27.   System.out.println(method1(11));
  28.  
  29.  }
  30.  
  31. }





10.What is the output of following program?


  1. package com.instanceofjava;
  2. class A
  3. {
  4.     
  5. public static void main(String [] args)
  6. {
  7.  
  8.   System.out.println(null);

  10.  }
  11.  
  12. }



Explanation:

What happens When System.out.println(null)?


  1. Print prime numbers? 
  2. Java Program Find Second highest number in an integer array 
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  7. Swap two numbers without using third variable in java 
  8. Find sum of digits in java 
  9. How to create immutable class in java 
  10. AtomicInteger in java 
  11. Check Even or Odd without using modulus and division  
  12. String Reverse Without using String API 
  13. Find Biggest substring in between specified character
  14. Check string is palindrome or not?
  15. Reverse a number in java? 
For more interview programs : Java Programs asked in interviews

Java Interview programs on Strings

Posted by: Instanceofjava Posted date: April 25, 2015 / comment : 0


1.Reverse a String Without using String API?

  1. package com.instaceofjava;
  2.  
  3. public class ReverseString {
  4.  
  5. public static void main(String[] args) {
  6.  
  7. String str="Hello world";
  8. String revstring="";
  9.  
  10. for(int i=str.length()-1;i>=0;--i){
  11. revstring +=str.charAt(i);
  12. }
  13.  
  14. System.out.println(revstring);
  15. }
  16. }


Program:

output: dlrow olleH.

 2)Sorting the String without using String API?


  1. package com.Instanceofjava;
  2.  
  3. public class SortString {
  4.  
  5.  public static void main(String[] args) {
  6.  
  7.   String original = "edcba";
  8.  int j=0;
  9.    char temp=0;
  10.  
  11.      char[] chars = original.toCharArray();
  12.      for (int i = 0; i <chars.length; i++) {
  13.          for ( j = 0; j < chars.length; j++) {
  14.          if(chars[j]>chars[i]){
  15.              temp=chars[i];
  16.              chars[i]=chars[j];
  17.               chars[j]=temp;
  18.           }
  19.      }
  20.   }
  21.  
  22.     for(int k=0;k<chars.length;k++){
  23.     System.out.println(chars[k]);
  24.    }
  25.  
  26.  }
  27. }

program:

output:abcde.

3.Sort the String with using String API?

program:
  1. package com.instanceofjava;
  2.  
  3.  public class SortString {
  4.  
  5.  public static void main(String[] args) {
  6.    String original = "edcba";
  7.  
  8.    char[] chars = original.toCharArray();
  9.    Arrays.sort(chars);
  10.  
  11.     String sorted = new String(chars);
  12.      System.out.println(sorted);
  13.  
  14. }
  15. }




OutPut:abcde

4.Check String is palindrome or not?

program:

 Solution #1:

  1. package com.instaceofjava; 
  2.  
  3. public class PalindromeDemo{ 
  4.  
  5. public static void main(String[] args) {
  6.  
  7. String str="MADAM";
  8. String revstring="";
  9.  
  10. for(int i=str.length()-1;i>=0;--i){
  11. revstring +=str.charAt(i);
  12. }
  13.  
  14. System.out.println(revstring);
  15.  
  16. if(revstring.equalsIgnoreCase(str)){
  17. System.out.println("The string is Palindrome");
  18. }
  19. else{
  20. System.out.println("Not Palindrome");
  21. }
  22.  
  23. }
  24.  
  25. }



  Output:

The string is Palindrome

Solution #2:

  1. package com.instaceofjava;
  2.  
  3.   import java.util.Scanner;
  4.  
  5.  public class Palindrome {
  6.  
  7. public static void main(String[] args)
  8. {
  9.  
  10. Scanner in = new Scanner(System.in);
  11.  
  12.  System.out.println("Enter a string");
  13.  String str=in.nextLine();
  14.  
  15. StringBuffer strone=new StringBuffer(str);
  16.  StringBuffer strtwo=new StringBuffer(strone);
  17.  
  18.   strone.reverse();
  19.  
  20. System.out.println("Orginal String ="+strtwo);
  21. System.out.println("After Reverse ="+strone);
  22.  
  23. if(String.valueOf(strone).compareTo(String.valueOf(strtwo))==0)
  24.    System.out.println("Result:Palindrome");
  25.    else
  26.     System.out.println("Result:Not Palindrome");
  27.  
  28.    }
  29.  
  30. }




 Output:

Enter a string
MOOM
Orginal String =MOOM
After Reverse =MOOM

Result:Palindrome

 5.Program to Check given number is palindrome or not?

Program:

  1.  package com.instaceofjava; 
  2.  
  3. import java.util.Scanner; 
  4.  
  5. public class Palindrome {
  6.  
  7. public static void main(String[] args)
  8. {
  9.  
  10. System.out.println("Please Enter a number : ");
  11.       int givennumber = new Scanner(System.in).nextInt();
  12.       int number=givennumber;
  13.        int reverse=0;
  14.         while (number != 0) {
  15.            int remainder = number % 10;
  16.             reverse = reverse * 10 + remainder;
  17.             number = number / 10;
  18.         }           
  19. if(givennumber == reverse)
  20.    System.out.println("Result:Palindrome");
  21.     else
  22.     System.out.println("Result:Not Palindrome");
  23.     }
  24.  
  25. }

 Output:

Please Enter a number :
535
Result:Palindrome.

 Also Read:


Top 16 Java Inheritance Interview questions for freshers and experienced

Posted by: Instanceofjava Posted date: April 25, 2015 / comment : 3


1.what is inheritance?
  • inheritance is one of the oops concepts in java.inheritance is concept of  getting properties of one class object to another class object.
  • Inheritance represents the IS-A relationship,also known as parent-child relationship.
2.what are the types of inheritance?

1.Multiple inheritance( java doesn't support multiple inheritance).
2.Multilevel inheritance.

3.How Inheritance can be implemented in java?
  • Inheritance can be implemented in JAVA using below two keywords:
1.extends
2.implements
  • extends is used for developing inheritance between two classes and two interfaces.
  • implements keyword is used to developed inheritance between interface and class.
4.Why we need to use Inheritance?

1.For Code Re usability.
2.For Method Overriding.

5.what is syntax of inheritance?

public class subclass extends superclass{

//all methods and variables declare here
}

6.what is multilevel inheritance?
  • Getting the properties from one class object to another class object level wise with different priorities.


6.what is Multiple inheritance?why Java Doesn't Support multiple Inheritance.
  • The concept of Getting the properties from multiple class objects to sub class object with same priorities is known as multiple inheritance.
  • In multiple inheritance there is every chance of multiple properties of multiple objects with  the same name available to the sub class object with same priorities leads for the ambiguity. also known as diamond problem. one class extending two super classes.
  • Because of multiple inheritance there is chance of the root object getting created more than once.
  • Always the root object i.e object of object class hast to be created only once.
  1. Because of above mentioned reasons multiple inheritance would not be supported by java.
  2. Thus in java a class can not extend more than one class simultaneously. At most a class can extend only one class.

 8.How do you implement multiple inheritance in java?
  • Using interfaces java can support multiple inheritance concept in java. in java can not extend more than one classes, but a class can implement more than one interfaces.
Program:

interface A{

}
interface B{
}
class C implements A,B{
}

9.Can a class extend itself?

  • No,A class can't extend itself.

10.What happens if super class and sub class having same field name?


  • Super class field will be hidden in the sub class. You can access hidden super class field in sub class using super keyword.

Top 20 Java Interview Questions on Constructors

Posted by: Instanceofjava Posted date: April 13, 2015 / comment : 1 ,


1. Define Constructor?

  • Constructor is a special method given in OOP language for creating and initializing object.
  • In java , constructor role is only initializing object , and new keyword role is crating object.

2.What are the Rules in defining a constructor?

  •  Constructor name should be same as class name.
  • It should not contain return type.
  • It should not contain Non Access Modifiers: final ,static, abstract, synchronized
  • In it logic return statement with value is not allowed.
  • It can have all four accessibility modifiers: private , public, protected, default
  • It can have parameters
  • It can have throws clause: we can throw exception from constructor.
  • It can have logic, as part of logic it can have all java legal statement except return statement with value.
  • We can not place return in constructor.

 3. Can we define a method with same name of class?

  • Yes, it is allowed to define a method with same class name. No compile time error and no runtime error is raised, but it is not recommended as per coding standards.

4.If we place return type in constructor prototype will it leads to Error?

  • No, because compiler and JVM considers it as a method.

5. How compiler and JVM can differentiate constructor and method definitions of both have same class name?

  • By using return type , if there is a return type it is considered as a method else it is considered as constructor.

6. How compiler and JVM can differentiate constructor and method invocations of both have same class name?

  • By using new keyword, if new keyword is used in calling then constructor is executed else method is executed.

7.Why return type is not allowed for constructor?

  •  As there is a possibility to define a method with same class name , return type is not allowed to constructor to differentiate constructor block from method block.

8.Why constructor name is same as class name?

  •  Every class object is created using the same new keyword , so it must have information about the class to which it must create object .
  • For this reason constructor name should be same as class name.

9.Can we declare constructor as private?

  •  Yes we can declare constructor as private.
  • All four access modifiers are allowed to
  •  constructor.
  • We should declare constructor as private for not to allow user to create object from outside of our class.
  • Basically we will declare private constructor in Singleton design pattern.
  • Read more at

constructor interview questions in java

10.Is Constructor definition is mandatory in class?

  •  No, it is optional . If we do not define a constructor compiler will define a default constructor.

11. Why compiler given constructor is called as default constructor?

  • Because it obtain all its default properties from its class.
  • They are
    1.Its accessibility modifier is same as its class accessibility modifier
    2.Its name is same as class name.
    3.Its does not have parameters and logic.

12. what is default accessibility modifier of default constructor?

  •  It is assigned from its class.

13.When compiler provides default constructor?

  •  Only if there is no explicit constructor defined by developer.

14.When developer must provide constructor explicitly?

  • If we want do execute some logic at the time of object creation, that logic may be object initialization logic or some other useful logic.

15.If class has explicit constructor , will it has default constructor?

  • No. compiler places default constructor only if there is no explicit constructor.
16.Programming interview questions on constructors





19.Differences between default constructor and no argument constructor

20.What is the order of execution of constructor with Non static blocks 


  1. Print prime numbers? 
  2. Java Program Find Second highest number in an integer array 
  3. Java Interview Program to find smallest and second smallest number in an array 
  4. Java Coding Interview programming Questions : Java Test on HashMap  
  6. Constructor chaining in java with example programs 
  8. Swap two numbers without using third variable in java 
  9. Find sum of digits in java 
  10. How to create immutable class in java 
  11. AtomicInteger in java 
  12. Check Even or Odd without using modulus and division  
  13. String Reverse Without using String API 
  14. Find Biggest substring in between specified character
  15. Check string is palindrome or not?
  16. Reverse a number in java? 
For more java programs: Top 50 java interview programs

Top 20 Oops Concepts Interview Questions

Posted by: Unknown Posted date: March 30, 2015 / comment : 3

1.What are the oops concepts in java?

basic oops concepts in java

 




2. What is encapsulation?

3.What is class ? 

 

  • A class is a specification or blue print or template of an object.
  • Class is a logical construct , an object has physical reality.
  • Class is a structure.
  • Class is a user defined data type in java
  • Class will acts as base for encapsulation.
  • Class contains variables and methods.


  1. package com.instanceofjava;
  2.  
  3. class Demo{
  4.  
  5. int a,b;
  6. void show(){
  7. }
  8.  
  9. }

4. What is an object?



  • Object is instance of class.
  • Object is dynamic memory allocation of class.
  • Object is an encapsulated form of all non static variables and non static methods of a particular class.
  • The process of creating objects out of class is known as instantiation.
  1. package com.instanceofjava;
  2.  
  3. class Test{
  4.  
  5. int a,b;
  6. void print(){
  7. System.out.println("a="+a);
  8. System.out.println("b="+b);
  9. }
  10.  
  11. public static void main(String [] args){
  12.    
  13.    Test obj= new Test();
  14.   obj.a=10;
  15.   obj.b=20;
  16.   obj.print();
  17. }
  18. }


Output:

  1. a=10
  2. b=20

5. What are the Object Characteristics?

  •  The three key characteristics of Object are
  • State
  • Behavior
  • Identity

State:

  • Instance variables value is called object state.
  • An object state will be changed if instance variables value is changed.

Behavior:

  • Behavior of an object is defined by instance methods.
  • Behavior of an object is depends on the messages passed to it.
  • So an object behavior depends on the instance methods.

Identity:

  • Identity is the hashcode of an object, it is a 32 bit integer number created randomly and assigned to an object by default by JVM.
  • Developer can also generate hashcode of an object based on the state of that object by overriding hashcode() method of java.lang.Object class.
  • Then if state is changed , automatically hashcode will be changed.

6.What is Inheritance?

  • As the name suggests , inheritance means to take something that already made.
  • One of the most important feature of Object oriented Programming. It is the concept that is used for re usability purpose.
  • Getting the properties from one class object to another class object.

7. How inheritance implemented in java?

  • Inheritance can be implemented in JAVA using below two keywords.
    1.extends
    2.implements
  • extends is used for developing inheritance between two classes or two interfaces, and implements keyword is used to develop inheritance between interface and class.


  1. package com.instanceofjava;
  2. class A{
  3.  
  4. }


  1. package com.instanceofjava;
  2. class B extends A{
  3.  
  4. }

8. What are the types of inheritances?

  • There are two types of inheritance
    1.Multilevel Inheritance
    2.Multiple Inheritance

Multilevel Inheritance:

  • Getting the properties from one class object to another class object level wise with some priority is known as multilevel inheritance.



  1. package com.instanceofjava;
  2.  
  3. class A{
  4.  
  5. }
  6.  
  7. class B extends A{
  8.   
  9. }
  10.   
  11. class C extends B{
  12.  
  13. }


Multiple Inheritance:


9. What is polymorphism?

  • Defining multiple methods with same name,
 Static polymorphism:
  • Defining multiple methods with same name with different parameters.
  • Is also known as method overloading.


  1. package com.instanceofjava;
  2. class Demo{
  3.   
  4. void add(){
  5. }
  6.   
  7. void add(int a, int b){
  8. }
  9.  
  10. void add(float a, float b){
  11.   
  12. }
  13. public static void main(String [] args){
  14.  Demo obj= new Demo();
  15.  
  16. obj.add();
  17. obj.add(1,2);
  18. obj.add(1.2f,1.4f);

  20. }

  22. }


 Dynamic Polymorphism:

  • Defining multiple methods with same signature in super class and sub class.
  • The sub most object method will be executed always.


 10. Similarities and differences between this and super keywords?

 this:
  • This is a keyword used to store current object reference.
  • It must be used explicitly if non -static variable and local variables name is same.
  • System.out.print(this); works fine
super:
  • Super is a keyword used to store super class non -static members reference in sub class object.
  • used to separate super class and sub class members if both have same name.
  • System.out.println(super); compilation Error

11.Top 10 interview Questions on Method overriding

12.Top 15 interview programming questions on abstract classes

13.Top 10 interview Question on interfaces

14.Java Quiz

15. Basic Method overloading interview questions in java 

16. Super keyword interview Questions in java

17.Top 10 java Interview questions on final keyword 

18. Top 10 basic interview questions and answers on this keyword

19. Top 20 java interview questions on constructors 

20. 19 Oops concepts explanation with example programs
  1. OOPS Introduction
  2. Encapsulation 
  3. Class and Object
  4. Four different ways to create objects in java 
  5. 5 different places to define object in java
  6. Polymorphism
  7. Method Overriding
  8. Inheritance
  9. Constructor
  10. Constructor Overloading 
  11. Constructor Chaining 
  12. Static constructor
  13. Static Keyword
  14. This Keyword
  15. Super Keyword
  16. Final Keyword
  17. Abstract class and interfaces 
  18. Abstract Class and abstract methods
  19. Interview questions on interfaces in java

  1. Print prime numbers? 
  2. Java Program Find Second highest number in an integer array 
  3. Java Interview Program to find smallest and second smallest number in an array 
  4. Java Coding Interview programming Questions : Java Test on HashMap 
  5. Constructor chaining in java with example programs 
  7. Swap two numbers without using third variable in java 
  8. Find sum of digits in java 
  9. How to create immutable class in java 
  10. AtomicInteger in java 
  11. Check Even or Odd without using modulus and division  
  12. String Reverse Without using String API 
  13. Find Biggest substring in between specified character
  14. Check string is palindrome or not?
  15. Reverse a number in java? 
For more interview programs : Top 60 Java Programs asked in interviews
Read Also:

1. Top 15 Garbage Collection Interview Questions

2. Top 10 Oops Concepts Interview Questions 

3. Top 15 Java Interview Questions on Constructors

4. Top 10 Inheritance Interview Questions

5. Interview Programs on Strings

6. 10 Interesting Core Java Interview Coding Questions and Answers

7. Top 20 Basic Java Interview Questions for Frehsers 

8. Top 10 interview Question on Static keyword. 

9.Top 20 Java interview Questions on Increment and Decrement operators

10.Top 10 Interview Questions on main() method

11. Top 12 Java Experienced interview Programming Questions on Strings

12.Pattern Programs in java Part-1

 13.Pattern Programs in java Part-2

14.Pattern Programs in java Part-3 

Top 15 Garbage Collection Interview Questions

Posted by: Unknown Posted date: March 30, 2015 / comment : 7

1.What is Garbage Collection in Java?

  • Garbage Collection is an automatic memory management feature.
  • The process of destroying unreferenced objects is called Garbage Collection.
  • Once object is unreferenced it is considered as unused object, hence JVM automatically destroys that object.
  • In java developers responsibility is only to creating objects and unreferencing those objects after usage.

2.How JVM can destroy unreferenced object?

  • JVM internally uses a daemon thread called "garbage collector" to destroy all unreferenced objects.
  • A daemon thread is a service thread. Garbage Collector thread is called daemon thread because it provides services to JVM to destroy unreferenced objects.
  • This thread is low priority thread. Since it is a low priority thread we can not guarantee this execution.

 3.So can you guarantee objects destruction?

  •  No, we can not guarantee objects destruction even though it is unreferenced, because we can not guarantee garbage collector execution.
  • So, we can confirm whether object is eligible for garbage collection or not.

4.Can we force garbage collector?

  • No, we can not force garbage collector to destroy objects , but we can request it.

5.How can we request JVM to start garbage collection process?

  • We have a method called gc() in system class as static method and also in Runtime class as non static method to request JVM to start garbage collector execution.
  • System.gc();
  • Runtime.getRuntime().gc();

6.What is the algorithm JVM internally uses for destroying objects?

  • "mark and swap" is the algorithm JVM internally uses.

7.Which part of the memory is involved in Garbage Collection?

  • Heap.

8.What is responsibility of Garbage Collector?

  • Garbage Collector frees the memory occupied by the unreachable objects during the java program by deleting these unreachable objects.
  • It ensures that the available memory will be used efficiently, but does not guarantee that there will be sufficient memory for the program to run.

9. When does an object become eligible for garbage collection?

  • An object becomes eligible for garbage collection when no live thread can access it.

10. What are the different ways to make an object eligible for garbage collection when it is no longer needed?

  • Set all available object references to "null" once the purpose of creating object is served.


  1. package com.instanceofjava;
  2.   
  3. class GarbageCollectionTest1{
  4.   
  5. public static void main(String [] args){
  6.  
  7. String str="garbage collection interview questions";
  8. // String object referenced by variable str and is not eligible for GC yet.
  9.  
  10. str=null;
  11. //String object referenced by variable str is eligible for GC
  12. }
  13. }

  • Make the reference variable to refer to another object. Decouple the reference variable from the object and set it refer to another object, so the object which was referring to before reassigning is eligible for Garbage Collection

  1. package com.instanceofjava;
  2.   
  3. class GarbageCollectionTest2{
  4.   
  5. public static void main(String [] args){
  6.  
  7. String str1="garbage collection interview questions";
  8. String str2="Top 15 garbage collection interview questions";
  9. // String object referenced by variable str1 and str2 and is not eligible for GC yet.
  10.  
  11. str1=str2;
  12. //String object referenced by variable str1 is eligible for GC
  13.  
  14. }
  15. }


11.What is purpose of overriding finalize() method?

  • The finalize() method should be overridden for an object to include the clean up code or to dispose of the system resources that should to be done before the object is garbage collected.

12.How many times does the garbage collector calls the finalize() method for an object? 

  • Only once.

13.What happens if an uncaught exception is thrown from during the execution of finalize() method of  an object?

  •  The exception will be ignored and the garbage collection (finalization) of that object terminates

14.What are the different ways to call garbage collector?

  • System.gc();
  • Runtime.getRuntime().gc();

15. How to enable /disable call of finalize() method of exit of application?

  • Runtime.getRuntime().runFinalizersOnExit(boolean value). passing the boolean value  true and false will enable or disable the finalize() call.



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