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List Interface:
  • List allows Duplicate Elements.
  • List having index.
  • List allows n number of null values.
  • List will display Insertion order with index.
  • List having classes like :
  • Vector
  • ArrayList
  • LinkedList
Vector:
  • Vector is a legacy class.
  • Vector is synchronized.
  • Vector initial capacity is 10.
  • Vector allows n number of null values
  • Vector can be accessible by index.
  • Vector allows Duplicate Elements.
Program for Vector:

package com.instanceofjavaforus;
import java.util.Enumeration;

import java.util.List;

import java.util.Vector;



public class A{

public static void main(String[] args) {


Vector vector=new Vector();


vector.add("indhu");

vector.add("sindhu");

vector.add("swathi");

vector.addElement(null);

vector.addElement(null);
Enumeration em=vector.elements();
while(em.hasMoreElements()){
System.out.println(em.nextElement());
}
}

}
Output:

indhu
sindhu
swathi
null

null



ArrayList:

  • ArrayList is not Synchronized.
  • Arraylist also allows Duplicate Elements.
  • ArrayList allows n number of null values.
  • Arraylist  having insertion order with index.
  • For retrieve purpose ArrayList is best choice.
  • ArrayList having Randaom Access Nature.
Program for ArrayList ;



package com.instanceofjava;
import java.util.ArrayList;
import java.util.ListIterator;

import java.util.List;



public class A{

public static void main(String[] args) {


             ArrayList arrayList=new ArrayList();




arrayList.add("sindhu");

arrayList.add("sindhu");

arrayList.add("swathi");

arrayList.add(null);

arrayList.add(null);
ListIterator it=arrayList.listIterator();
while(it.hasNext()){
System.out.println(it.hasNext());
}
}
}

Output:
sindhu
sindhu
swathi
null
null

LinkedList:


  • LinkedList is not synchronized.
  • LinkedList allows n number of null values.
  • LinkedList allows Duplicate Elements.
  • LinkedList  having insertion order with index.
  • Insertion and Deletion purpose LinkedList is better choice.
  • LinkedList Follows Doubly linked list Structure.
Program for LinkedList:


package com.instanceofjava;
import java.util.LinkedList;
import java.util.ListIterator;
import java.util.List;

public class A{

public static void main(String[] args) {

  LinkedList linkedList=new LinkedList();




linkedList.add("sindhu");

linkedList.add("sindhu");

linkedList.add("swathi");

linkedList.add(null);

linkedList.add(null);

ListIterator it=linkedList.listIterator();
while(it.hasNext()){
System.out.println(it.hasNext());
}
}
}

Output:


sindhu
sindhu
swathi
null
null
  • In List interface if you want  to add elements we can use add() method.
  • If you want  to remove elements we can use remove() method.







Instance Of Java

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1 comments for Collections List

  1. Put more interview question and
    Answer about hibernate and spring

    ReplyDelete

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