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.

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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