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Selasa, 22 Maret 2016

Core java Interview Questions

Basic operators in java

Kris Kimcil 07.52 Komentar

Types of Operators in Java:

Arithmetic Operators
Bit-wise Operators
Logical Operators
Relational Operators
Assignment Operators
Misc Operators

Java operator precedence

Arithmetic Operators

Arithmetic operators are used in mathematical expressions.
Following are the arithmetic operators in java.

+ : Addition
- : Subtraction
* : Multiplication
/ : Division
% : Modulus

Bit wise Operators:

Bit wise operators operates on individual bits of operands.
Following are the Bit-wise operators in java.
Bitwise operators in java

~ : Bit wise unary not
& : Bit wise And
| : Bit wise OR
^ : Bit wise Exclusive OR
>> : Shift Right
>>> : Shift right zero fill
<< :Shift left

Logical Operators:

&& : Logical AND
|| : Logical OR
! : Logical NOT

Relational Operators in java

== : Equal to
!= : Not Equal to
< : Less Than
> : Greater Than
>= : Greater Than or Equal to
<= : Less Than or Equal to

Assignment Operators:

= : Simple Assignment
+= : Add and assign
-= : Subtract and assign
*= : Multiply and assign
%= : Modulus and assign
/= : Divide and assign
&= : Bit wise AND assignment
|= : Bit wise assignment OR
^= : Bit wise Exclusive OR assignment
>>= : Shift Right assignment
>>>= : Shift right zero fill assignment
<<= : Shift left assignment

Misc Operators:

Increment and Decrement operators:

++ : increment
-- : decrement

Top 20 Basic Java Interview Programs on Increment Decrement operators

Conditional Operator: (?:)

Also known as ternary operator
Example: int a= 1>2?1:2;

Ternary operator in java

Instanceof Operator

Instance of operator is used to test whether that object is belong to that class type or not.
If that object belongs to that class it returns true .otherwise it returns false.
Instance of operator is also known as comparison operator.because it compares with the instance of type.

Instanceof operator in java

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Senin, 21 Maret 2016

Top 30 frequently asked java interview programs for freshers

Kris Kimcil 23.19 Komentar

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Core java Interview Questions

Java Example program convert Decimal to Binary

Kris Kimcil 07.41 Komentar

We can convert binary to decimal in three ways
1.Using Integer.toBinaryString(int num);
2.Using Stack
3.Using Custom logic

1.Write a Java Program to convert decimal to binary in java using Integer.toBinaryString(int num)

import java.util.Scanner;
public class ConvertDecimalToBinary{
/**
*www.instanceofjava.com
*/
public static void main(String[] args) {
System.out.println("\nBinary representation of 1: ");
System.out.println(Integer.toBinaryString(1));
System.out.println("\nBinary representation of 4: ");
System.out.println(Integer.toBinaryString(4));
System.out.println("Binary representation of 10: ");
System.out.println(Integer.toBinaryString(10));
System.out.println("\nBinary representation of 12: ");
System.out.println(Integer.toBinaryString(12));
System.out.println("\nBinary representation of 120: ");
System.out.println(Integer.toBinaryString(120));
System.out.println("\nBinary representation of 500: ");
System.out.println(Integer.toBinaryString(500));
}
}

Output:

Binary representation of 1:
1
Binary representation of 4:
100
Binary representation of 10:
1010
Binary representation of 12:
1100
Binary representation of 120:
1111000
Binary representation of 500:
111110100

2.Write a Java Program to convert decimal to binary in java

import java.util.Scanner;
import java.util.Stack;
public class ConvertDecimalToBinary{
/**
*www.instanceofjava.com
*/
public static void main(String[] args) {
Scanner in = new Scanner(System.in);
// Create Stack object
Stack<Integer> stack = new Stack<Integer>();
//Take User input from keyboard
System.out.println("Enter decimal number: ");
int num = in.nextInt();
while (num != 0)
{
int d = num % 2;
stack.push(d);
num /= 2;
}
System.out.print("\nBinary representation is:");
while (!(stack.isEmpty() ))
{
System.out.print(stack.pop());
}
System.out.println();
}
}
}

Output:

Enter decimal number:
12
Binary representation is:1100

3.Write a Java Program to convert decimal to binary in java

import java.util.Scanner;
public class ConvertDecimalToBinary{
/**
*www.instanceofjava.com
*/
public static void convertDeciamlToBinary(int num){
int binary[] = new int[40];
int index = 0;
while(num > 0){
binary[index++] = num%2;
num = num/2;
}
for(int i = index-1;i >= 0;i--){
System.out.print(binary[i]);
}
}
public static void main(String[] args) {
System.out.println("Binary representation of 1: ");
convertDeciamlToBinary(1);
System.out.println("\nBinary representation of 4: ");
convertDeciamlToBinary(4);
System.out.println("\nBinary representation of 10: ");
convertDeciamlToBinary(10);
System.out.println("\nBinary representation of 12: ");
convertDeciamlToBinary(12);
}
}

Output:

Binary representation of 1:
1
Binary representation of 4:
100
Binary representation of 10:
1010
Binary representation of 12:
1100

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Java Example Program to convert binary to decimal

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Core java Interview Questions

Java Example Program to convert binary to decimal

Kris Kimcil 07.06 Komentar

Famous interview java question on conversions .
We can convert binary to decimal in two ways
1.Using Integer.parseInt() method
2.Using custom logic

1.Write a Java Program to convert binary to decimal number in java without using Integer.parseInt() method.

import java.util.Scanner;
public class DecimalFromBinary {
/**
*www.instanceofjava.com
*/
public static void main(String[] args) {
Scanner in = new Scanner( System.in );
System.out.println("Enter a binary number: ");
int binarynum =in.nextInt();
int binary=binarynum;
int decimal = 0;
int power = 0;
while(true){
if(binary == 0){
break;
} else {
int tmp = binary%10;
decimal += tmp*Math.pow(2, power);
binary = binary/10;
power++;
}
}
System.out.println("Binary="+binary+" Decimal="+decimal); ;
}
}

Output:

Enter a binary number:
101
Binary=101 Decimal=5

2.Write a Java Program to convert binary to decimal number in java using Integer.parseInt() method.

import java.util.Scanner;
public class ConvertBinaryToDecimal{
/**
*www.instanceofjava.com
*/
public static void main(String[] args) {
Scanner in = new Scanner( System.in );
System.out.println("Enter a binary number: ");
String binaryString =input.nextLine();
System.out.println("Result: "+Integer.parseInt(binaryString,2));
}
}

Output:

Enter a binary number:
001
Result: 1

java program to convert binary to decimal

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Java Example program convert Decimal to Binary

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Kamis, 17 Maret 2016

Hashtable java Collections interview Questions

Get collection values from hashtable example

Kris Kimcil 03.24 Komentar

1.Basic java collection framework example program to get Value collection from hashtable

Collection values() This method used to get collection of values
Important note is that if any value is removed from set the original hashtable key also removed

package com.setviewHashtable;
import java.util.Hashtable;
import java.util.Enumeration;
import java.util.Iterator;
import java.util.Set;
public class HashtableExample{
public static void main(String[] args) {
//create Hashtable object
Hashtable<String,String> hashtable = new Hashtable<String,String>();
//add key value pairs to Hashtable
hashtable.put("1","Java Interview Questions");
hashtable.put("2","Java Interview Programs");
hashtable.put("3","Concept and example program");
hashtable.put("4","Concept and interview Questions");
hashtable.put("5","Java Quiz");
hashtable.put("6","Real time examples");
Collection c = hashtable.values();
System.out.println("Values of Collection created from Hashtable are :");
//iterate through the Set of keys
Iterator itr = c.iterator();
while(itr.hasNext())
System.out.println(itr.next());
c.remove("Java Quiz");
System.out.println("Elements in hash table");
Enumeration e=hashtable.elements();
while (e.hasMoreElements()) {
System.out.println(e.nextElement());
}
}
}

Output:

Values of Collection created from Hashtable are :
Real time examples
Java Quiz
Concept and interview Questions
Concept and example program
Java Interview Programs
Java Interview Questions
Elements in hash table
Real time examples
Concept and interview Questions
Concept and example program
Java Interview Programs
Java Interview Questions

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Hashtable java Collections interview Questions

Java Collections example program Get Set view of Keys from Hashtable example

Kris Kimcil 03.04 Komentar

1.Basic java collection framework example program to get set view from hashtable

Set keySet() This method used to get set view of the keys of hashtable
Important note is that if any key is removed from set the original hashtable key also removed

package com.setviewHashtable;
import java.util.Hashtable;
import java.util.Enumeration;
import java.util.Iterator;
import java.util.Set;
public class HashtableExample{
public static void main(String[] args) {
//create Hashtable object
Hashtable<String,String> hashtable = new Hashtable<String,String>();
//add key value pairs to Hashtable
hashtable.put("1","Java Interview Questions");
hashtable.put("2","Java Interview Programs");
hashtable.put("3","Concept and example program");
hashtable.put("4","Concept and interview Questions");
hashtable.put("5","Java Quiz");
hashtable.put("6","Real time examples");
Set st = hashtable.keySet();
System.out.println("Set created from Hashtable Keys contains :");
//iterate through the Set of keys
Iterator itr = st.iterator();
while(itr.hasNext())
System.out.println(itr.next());
st.remove("1");
System.out.println("Elements in hash table");
Enumeration e=hashtable.keys();
while (e.hasMoreElements()) {
System.out.println(e.nextElement());
}
}
}

Output:

Set created from Hashtable Keys contains :
6
5
4
3
2
1
Elements in hash table
6
5
4
3
2

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Rabu, 16 Maret 2016

java Collections interview Questions

Java collections interview programming questions

Kris Kimcil 10.09 Komentar

Introduction to Collection Framework

Collection set interface:

Collection Set Interface

Hashset Class in Collection framework: (Java programming questions)

LinkedHashSet Class in Collection framework: (Java programming questions)

Treeset Class in Collection framework: (Java programming questions)

Collection List Interface:

Collection List Interface

ArrayList Class in Collection framework: (Java programming questions)

Map Interface In java

Map interface

HashMap Class in Collection framework: (Java programming questions)

Hashtable Class in Collection framework: (Java interview programming questions)

Java collections programming interview questions

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Hashtable java Collections interview Questions

Remove all elements from hashtable java example

Kris Kimcil 02.24 Komentar

1.Basic java example program to remove all elements from hashtable

Object remove(Object key) This method used to remove value pair from hashtable
void clear() this method removes all elements from hashtable

package com.removevalueHashtable;
import java.util.Hashtable;
import java.util.Enumeration;
public class HashtableExample{
public static void main(String[] args) {
//create Hashtable object
Hashtable<String,String> hashtable = new Hashtable<String,String>();
//add key value pairs to Hashtable
hashtable.put("1","Java Interview Questions");
hashtable.put("2","Java Interview Programs");
hashtable.put("3","Concept and example program");
hashtable.put("4","Concept and interview Questions");
hashtable.put("5","Java Quiz");
hashtable.put("6","Real time examples");
Object obj = ht.remove("2");
System.out.println(obj + " Removed from Hashtable");
Enumeration e=hashtable.elements();
while (e.hasMoreElements()) {
System.out.println(e.nextElement());
}
hashtable.clear();
System.out.println("Total key value pairs in Hashtable are : " + hashtable.size());
}
}

Output:

Java Interview Programs Removed from Hashtable
Real time examples
Java Quiz
Concept and interview Questions
Concept and exampe program
Java Interview Questions
Total key value pairs in Hashtable are : 0

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Hashtable java Collections interview Questions

Remove key value pair from hashtable java example

Kris Kimcil 02.16 Komentar

1.Basic java example program to iterate keys of hashtable

Object remove(Object key) This method used to remove value pair from hashtable

package com.removevalueHashtable;
import java.util.Hashtable;
import java.util.Enumeration;
public class HashtableExample{
public static void main(String[] args) {
//create Hashtable object
Hashtable<String,String> hashtable = new Hashtable<String,String>();
//add key value pairs to Hashtable
hashtable.put("1","Java Interview Questions");
hashtable.put("2","Java Interview Programs");
hashtable.put("3","Concept and example program");
hashtable.put("4","Concept and interview Questions");
hashtable.put("5","Java Quiz");
hashtable.put("6","Real time examples");
Object obj = ht.remove("2");
System.out.println(obj + " Removed from Hashtable");
Enumeration e=hashtable.elements();
// display search result
while (e.hasMoreElements()) {
System.out.println(e.nextElement());
}
}
}

Output:

Java Interview Programs Removed from Hashtable
Real time examples
Java Quiz
Concept and interview Questions
Concept and exampe program
Java Interview Questions

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Hashtable java Collections interview Questions

Iterate through values of hashtable java

Kris Kimcil 01.56 Komentar

1.Basic java example program to iterate keys of hashtable

Enumeration elements() This method used to get values of hashmap

package com.iteartekeysHashtable;
import java.util.Hashtable;
import java.util.Enumeration;
public class HashtableExample{
public static void main(String[] args) {
//create Hashtable object
Hashtable<String,String> hashtable = new Hashtable<String,String>();
//add key value pairs to Hashtable
hashtable.put("1","Java Interview Questions");
hashtable.put("2","Java Interview Programs");
hashtable.put("3","Concept and example program");
hashtable.put("4","Concept and interview Questions");
hashtable.put("5","Java Quiz");
hashtable.put("6","Real time examples");
Enumeration e=hashtable.elements();
// display search result
while (e.hasMoreElements()) {
System.out.println(e.nextElement());
}
}
}

Output:

Real time examples
Java Quiz
Concept and interview Questions
Concept and example program
Java Interview Programs
Java Interview Questions

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Core java Interview Questions

Method overloading interview questions java

Kris Kimcil 00.03 Komentar

1.What is Method in java?

Method is a sub block of a class that contains logic of that class.
logic must be placed inside a method, not directly at class level, if we place logic at class level compiler throws an error.
So class level we are allowed to place variables and methods.
The logical statements such as method calls, calculations and printing related statements must be placed inside method, because these statements are considered as logic.
For more information @ Methods in java

package com.instanceofjava;
class sample{
int a;
int b;
System.out.println("instance of java"); // compiler throws an error.
}

package com.instanceofjava;
class sample{
static int a=10;
public static void main(String args[]){

System.out.println(a); // works fine,prints a value:10

}
}

2.What is meant by method overloading in java?

Defining multiple methods with same name is known as polymorphism.
Defining multiple methods with same name and with different arguments known as method overloading.

package com.instanceofjava;
class A{
public void show(int a){
System.out.println("saidesh");
}
public void show(int a,int b){
System.out.println("ajay");
}
public void show(float a){
System.out.println("vinod");
}
public static void main(String args[]){
A a=new A();
a.show(10);
a.show(1,2);
a.show(1.2);
}
}

Output:

saidesh
ajay
vinod

3.What are the other names for method overloading?

Method overloading also known as static polymorphism or compile time polymorphism because at compile time itself we can tell which method going to get executed based on method arguments.
So method overloading also called as static binding.

4.What are the basic rules of method overloading?

Defining a method with same name and differ in number of arguments
Defining a method with same name and differ in type of arguments
Defining a method with same name and differ in order of type of arguments
Return type of the method not involved in method overloading.

5.Can we overload static methods in java?

Yes. We can overload static methods in java.
Method overriding is not possible but method overloading is possible for static methods.
Before that lets see about method overloading in java.

lets see an example java program which explains static method overloading.

class StaticMethodOverloading{
public static void staticMethod(){
System.out.println("staticMethod(): Zero arguments");
}
public static void staticMethod(int a){
System.out.println("staticMethod(int a): one argument");
}
public static void staticMethod(String str, int x){
System.out.println("staticMethod(String str, int x): two arguments");
}
public static void main(String []args){
StaticMethodOverloading.staticMethod();
StaticMethodOverloading.staticMethod(12);
StaticMethodOverloading.staticMethod("Static method overloading",10);
}
}

Output:

staticMethod(): Zero arguments
staticMethod(int a): one argument
staticMethod(String str, int x): two arguments

6.Can we overload main method in java?

Yes we can overload main method in java

Java Program to overload main method in java

class mainMethodOverloading{
public static void main(boolean x){
System.out.println("main(boolean x) called ");
}
public static void main(int x){
System.out.println("main(int x) called");
}
public static void main(int a, int b){
System.out.println("main(int a, int b) called");
}
public static void main(String []args){
System.out.println("main(String []args) called ");
mainMethodOverloading.main(true);
mainMethodOverloading.main(10);
mainMethodOverloading.main(37,46);
}
}

Output:

main(String []args) called
main(boolean x) called
main(int x) called
main(int a, int b) called

7.Can we overload constructors in java?

Yes we can overload constructor in java

package instanceofjava;
class ConstructorChaining{
int a,b
ConstructorChaining(){
this(1,2);
System.out.println("Default constructor");
}
ConstructorChaining(int x , int y){
this(1,2,3);
a=x;
b=y;
System.out.println("Two argument constructor");
}
ConstructorChaining(int a , int b,int c){
System.out.println("Three argument constructor")
}
public static void main(String[] args){
ConstructorChaining obj=new ConstructorChaining();
System.out.println(obj.a);
System.out.println(obj.b);
}
}

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Top 10 Interview Programs and questions on method overriding in java

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Selasa, 15 Maret 2016

Hashtable java Collections interview Questions

Iterate through keys of hashtable java

Kris Kimcil 22.58 Komentar

1.Basic java example program to iterate keys of hashtable

Enumeration keys() This method used to get keys of hashmap

package com.iteartekeysHashtable;
import java.util.Hashtable;
import java.util.Enumeration;
public class HashtableExample{
public static void main(String[] args) {
//create Hashtable object
Hashtable<String,String> hashtable = new Hashtable<String,String>();
//add key value pairs to Hashtable
hashtable.put("1","Java Interview Questions");
hashtable.put("2","Java Interview Programs");
hashtable.put("3","Concept and exampe program");
hashtable.put("4","Concept and interview Questions");
hashtable.put("5","Java Quiz");
hashtable.put("6","Real time examples");
Enumeration e=hashtable.keys();
// display search result
while (e.hasMoreElements()) {
System.out.println(e.nextElement());
}
}
}

Output:

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Hashtable java Collections interview Questions

Check particular value exist in hashtable

Kris Kimcil 22.43 Komentar

1.Basic java example program to check particular value exist in hashtable

boolean contains(Object value) This method used to check particular value exist in hashtable

package com.CheckElelemtHashtable;
import java.util.Hashtable;
import java.util.Enumeration;
public class HashtableExample{
public static void main(String[] args) {
//create Hashtable object
Hashtable<String,String> hashtable = new Hashtable<String,String>();
//add key value pairs to Hashtable
hashtable.put("1","Java Interview Questions");
hashtable.put("2","Java Interview Programs");
hashtable.put("3","Concept and exampe program");
hashtable.put("4","Concept and interview Questions");
hashtable.put("5","Java Quiz");
hashtable.put("6","Real time examples");
/*
To check whether a particular value exists in Hashtable we need to use
boolean containsKey(Object value) method of Hashtable class.
if the Hashtable contains mapping for specified value It returns true
otherwise returns false.
*/
boolean isExists = hashtable.contains("Java Quiz");
System.out.println("Java Quiz exists in Hashtable ? : " + isExists);
System.out.println("Hashtable values : ");
Enumeration e=hashtable.elements();
// display search result
while (e.hasMoreElements()) {
System.out.println(e.nextElement());
}
}
}

Output:

Java Quiz exists in Hashtable ? : true
Hashtable values :
Real time examples
Java Quiz
Concept and interview Questions
Concept and exampe program
Java Interview Programs
Java Interview Questions

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Hashtable java Collections interview Questions

Check if a particular key exists in Java Hashtable example

Kris Kimcil 22.34 Komentar

1.Basic java example program to check particular element exist in hashtable

boolean containsKey(Object key) This method used to check particular key exist in hashtable

package com.CheckElelemtHashtable;
import java.util.Hashtable;
import java.util.Iterator;
public class HashtableExample{
public static void main(String[] args) {
//create Hashtable object
Hashtable<String,String> hashtable = new Hashtable<String,String>();
//add key value pairs to Hashtable
hashtable.put("1","Java Interview Questions");
hashtable.put("2","Java Interview Programs");
hashtable.put("3","Concept and exampe program");
hashtable.put("4","Concept and interview Questions");
hashtable.put("5","Java Quiz");
hashtable.put("6","Real time examples");
/*
To check whether a particular key exists in Hashtable we need to use
boolean containsKey(Object key) method of Hashtable class.
if the Hashtable contains mapping for specified key It returns true
otherwise returns false.
*/
boolean isExists = hashtable.containsKey("5");
System.out.println("5 exists in Hashtable ? : " + isExists);
Enumeration e=hashtable.elements();
System.out.println("Display result:");
// display search result
while (e.hasMoreElements()) {
System.out.println(e.nextElement());
}
}
}

Output:

5 exists in Hashtable ? : true
Hashtable values :
Display result:
Real time examples
Java Quiz
Concept and interview Questions
Concept and exampe program
Java Interview Programs
Java Interview Questions

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Core java Interview Questions

Non static blocks in java example

Kris Kimcil 04.17 Komentar

Non Static Blocks in java

When ever object created non static blocks will be executed before the execution of constructor
Non static blocks are class level block which does not have prototype

package nonstaticblocks;
public class A {
{
System.out.println("non static block executed");
}
}

What is the need of Non static blocks in java?

To execute any logic whenever object is created irrespective of constructor used in object creation.

Who will execute Non static blocks?

Non static blocks are automatically called by JVM for every object creation in java stack area

How many Non static blocks we can create?

We can create any number of Non static blocks

Order of execution of non static blocks

Order of execution of non static blocks will be order as they are defined.

package nonstaticblocks;
public class A {
{
System.out.println("first block");
}
{
System.out.println("second block");
}
{
System.out.println("third block");
}
public static void main(String[] args) {
A obj= new A();
}
}

Output:

first block
second block
third block

Order of execution of non static blocks with respect to constructor?

non static blocks in java example program

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java Collections interview Questions LinkedHashSet

Remove all elements LinkedHashSet example

Kris Kimcil 03.41 Komentar

1.Basic java example program to remove all elements in linkedhashset

clear() This method used to remove all elements from Linkedhashset.

package com.removeelementLinkedhashset;
import java.util.LinkedHashSet;
import java.util.Iterator;
public class LinkedHashsetExample{
public static void main(String[] args) {
LinkedHashSet<String> linkedhashset = new LinkedHashSet<>();
linkedhashset.add("Java Interview Questions");
linkedhashset.add("Java interview program");
linkedhashset.add("Concept and example program");
linkedhashset.add("Concept and interview questions");
linkedhashset.add("Java Quiz");
System.out.println("LinkedHashSet before removal : " + linkedhashset);
boolean blnRemoved = linkedhashset.remove("Java Quiz");
System.out.println("Was Java Quiz removed from LinkedHashSet ? " + blnRemoved);
System.out.println("LinkedHashSet after removal : ");
Iterator it=linkedhashset.iterator();
while(it.hasNext()){
System.out.println(it.next());
}
linkedhashset.clear();
System.out.println("LinkedHashSet after removal all elements");
}
}

Output:

LinkedHashSet before removal : [Java Interview Questions, Java interview program, Concept
and example program, Concept and interview questions, Java Quiz]
Was Java Quiz removed from LinkedHashSet ? true
LinkedHashSet after removal :
Java Interview Questions
Java interview program
Concept and example program
Concept and interview questions
LinkedHashSet after removal all elements :[]

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Core java Interview Questions

Differences between Default constructor and no argument constructor in java

Kris Kimcil 03.19 Komentar

Differences between default constructor and no argument constructor

Default Constructor in java:

When we write a class without any constructor then at compilation time java compiler creates a default constructor in our class.
The accessibility modifier of the default constructor is same as accessibility modifier of class.
The allowed accessibility modifier are public and default.
Default constructor added by java compiler this constructor does not have anything except super(); call.

package constructor;
public class A {
}

package constructor;
public class A {
A(){
super();
}
}

If our class have any constructor then java compiler does not create default constructor

No-argument Constructor in java:

As a developer we can create our own constructor with no arguments is known as no-argument constructor.
It can have all four accessibility modifiers as it is defined by developer.
So allowed accessibility modifiers are public, private, protected and default
It can have logic including super call.

package constructor;
public class A {
A(){
super();
System.out.println("no -argument constructor");
}
}

The common point between default and no-argument constructor
Both does not have any arguments.
And one more point we need to remember that in no-argument constructor also by default first statement will be super() call which is added by java compiler if it does not have.

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java Collections interview Questions java programs for freshers LinkedHashSet

Remove specified element from Java LinkedHashSet example

Kris Kimcil 02.40 Komentar

1.Basic java example program to remove particular element in linkedhashset

boolean remove(Object o) This method used to remove specified element from Linkedhashset.

package com.removeelementLinkedhashset;
import java.util.LinkedHashSet;
import java.util.Iterator;
public class LinkedHashsetExample{
public static void main(String[] args) {
LinkedHashSet<String> linkedhashset = new LinkedHashSet<>();
linkedhashset.add("Java Interview Questions");
linkedhashset.add("Java interview program");
linkedhashset.add("Concept and example program");
linkedhashset.add("Concept and interview questions");
linkedhashset.add("Java Quiz");
System.out.println("LinkedHashSet before removal : " + linkedhashset);
boolean blnRemoved = linkedhashset.remove("Java Quiz");
System.out.println("Was Java Quiz removed from LinkedHashSet ? " + blnRemoved);
System.out.println("LinkedHashSet after removal : ");
Iterator it=linkedhashset.iterator();
while(it.hasNext()){
System.out.println(it.next());
}
}
}

Output:

LinkedHashSet before removal : [Java Interview Questions, Java interview program, Concept
and example program, Concept and interview questions, Java Quiz]
Was Java Quiz removed from LinkedHashSet ? true
Java Interview Questions
Java interview program
Concept and example program
Concept and interview questions

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java Collections interview Questions LinkedHashSet

Check if a particular element exists in Java LinkedHashSet Example

Kris Kimcil 02.25 Komentar

1.Basic java example program to check particular element is exists in linkedhashset

boolean contains(Object o) This method Returns true if this set contains the specified element

package com.checkelementhashset;
import java.util.LinkedHashSet;
import java.util.Iterator;
public class LinkedHashsetExample{
public static void main(String[] args) {
LinkedHashSet<String> linkedhashset = new LinkedHashSet<>();
linkedhashset.add("Java Interview Questions");
linkedhashset.add("Java interview program");
linkedhashset.add("Concept and example program");
linkedhashset.add("Concept and interview questions");
linkedhashset.add("Java Quiz");
/*
To check whether a particular value exists in LinkedHashSet we need to use
boolean contains(Object value) method of HashSet class.
this method returns true if the LinkedHashSet contains the value, otherwise returns false.
*/
boolean isExists = linkedhashset.contains("Java Quiz");
System.out.println("Java Quiz exists in LinkedHashSet? : " + isExists);
Iterator it=linkedhashset.iterator();
while(it.hasNext()){
System.out.println(it.next());
}
}
}

Output:

Java Quiz exists in LinkedHashSet ? : true
Java Interview Questions
Java interview program
Concept and example program
Concept and interview questions
Java Quiz

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exception handling interview questions finally with return

Return statement in finally block in java

Kris Kimcil 00.32 Komentar

Can we write return statement in finally block

Finally block will executes always excepts system.exit().
So if we are returning some value in finally means it will be returned always
Finally will executed so method always returns finally return value and no need of keeping return value at end of the method.
And in finally after return if we keep some statement those statement will be treated as dead code.

i)Return statement in finally block