java.util.Collections.reverse() Method


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Description

The reverse(List<?>) method is used to reverse the order of the elements in the specified list.

Declaration

Following is the declaration for java.util.Collections.reverse() method.

public static void reverse(List<?> list)			 

Parameters

  • list -- This is the list whose elements are to be reversed.

Return Value

  • NA

Exception

  • UnsupportedOperationException -- This is if the specified list or its list-iterator does not support the set operation.

Example

The following example shows the usage of java.util.Collections.reverse()

package com.tutorialspoint;

import java.util.*;

public class CollectionsDemo {
   public static void main(String[] args) {
   // create array list object
   ArrayList arrlst = new ArrayList();
      
   // populate the list
   arrlst.add("A");
   arrlst.add("B");
   arrlst.add("C");
   arrlst.add("D");
   arrlst.add("E");

   System.out.println("The initial list is :"+arrlst);
      
   // reverse the list
   Collections.reverse(arrlst);
      
   System.out.println("The Reverse List is :"+arrlst);
   }
}

Let us compile and run the above program, this will produce the following result.

The initial list is :[A, B, C, D, E]
The Reverse List is :[E, D, C, B, A]

java_util_collections.htm

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