Java.util.ArrayList.contains() Method


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Description

The java.util.ArrayList.contains(Object) method returns true if this list contains the specified element.

Declaration

Following is the declaration for java.util.ArrayList.contains() method

public boolean contains(Object o)

Parameters

o − The element whose presence in this list is to be tested.

Return Value

This method returns true if this list contains the specified element.

Exception

NA

Example

The following example shows the usage of java.util.Arraylist.contains method.

Live Demo
package com.tutorialspoint;

import java.util.ArrayList;

public class ArrayListDemo {
   public static void main(String[] args) {
      
      // create an empty array list with an initial capacity
      ArrayList<Integer> arrlist = new ArrayList<Integer>(8);

      // use add() method to add elements in the list
      arrlist.add(20);
      arrlist.add(25);
      arrlist.add(10);
      arrlist.add(15);        
          
      // let us print all the elements available in list
      for (Integer number : arrlist) {
         System.out.println("Number = " + number);
      }

      // list contains element 10
      boolean retval = arrlist.contains(10); 
        
      if (retval == true) {
         System.out.println("element 10 is contained in the list");
      } else {
         System.out.println("element 10 is not contained in the list");
      }
         
      // list does not contain element 30
      boolean retval2 = arrlist.contains(30);
        
      if (retval2 == true) {
         System.out.println("element 30 is contained in the list");
      } else {
         System.out.println("element 30 is not contained in the list");    
      }
   }
}

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

Number = 20
Number = 25
Number = 10
Number = 15
element 10 is contained in the list
element 30 is not contained in the list

java_util_arraylist.htm


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