CodesJava

Easy learning with example program codes

how to shuffle elements in an arraylist in java?


ArrayList:

ArrayList class extends AbstractList and implements the List interface. It uses dynamic arrays for storing elements. It maintains insertion order. ArrayList can contain duplicate elements. It is not synchronized.

Note: ArrayList provides the facility of random access because of it is index based.

We can use shuffle() method which generates different order of output, to shuffle elements in an arraylist in java.

Example:

package com.codesjava;
 
import java.util.ArrayList;
import java.util.Collections;
 
public class Test {
  public static void main(String args[]){
	ArrayList<String> arrayList = new ArrayList<String>();
	arrayList.add("Jai");
	arrayList.add("Mahesh");
	arrayList.add("Vivek");
	arrayList.add("Naren");
	arrayList.add("Hemant");
	arrayList.add("Vishal");
	System.out.println("Actual ArrayList:"+arrayList);
	Collections.shuffle(arrayList);
        System.out.println("Results after shuffle operation:" + arrayList);       
        Collections.shuffle(arrayList);
        System.out.println("Results after shuffle operation:" + arrayList);
  }
}

Output

Actual ArrayList:[Jai, Mahesh, Vivek, Naren, Hemant, Vishal]
Results after shuffle operation:[Naren, Vivek, Vishal, Mahesh, Hemant, Jai]
Results after shuffle operation:[Vishal, Mahesh, Naren, Hemant, Jai, Vivek]


Copyright © 2018 CodesJava DMCA.com Protection Status SiteMap