Java List containsAll() Method

The containsAll() method of List interface returns a Boolean value 'true' if this list contains all the elements of the invoked collection.

Syntax

Parameters

The parameter 'c' represents the collection to be checked for occurrence in this list.

Specified By

containsAll in interface Collection<E>

Throws:

ClassCastException- If the types of one or more elements in the specified collection are not compatible with this list.

NullPointerException- If the specified collection is null or it contains one or more null elements, and this list does not allow null elements.

Returns:

The containsAll() method returns Boolean value 'true' if this list contains all the elements in the invoked collection, else it returns false.

Example 1

import java.util.LinkedList;
import java.util.List;

public class JavaListContainsAllExample1 {
public static void main(String[] args) {
        List<Integer> list= new LinkedList<>();
for (int i=0;i<11;i++){
list.add(i);
        }
System.out.println("Total elements in the list : "+list);
        List<Integer> list1= new LinkedList<>();
for (int i=0;i<11;i++){
if(i%2==0) {
                list1.add(i);
            }
        }
//returns true,  if this list contains all the elements of list1.
Boolean bool=list.containsAll(list1);
if (bool) {
System.out.println("Contains All method will return " + bool);
        }
else{
System.out.println("Contains All method will return " + bool);
        }
    }
}

Test it Now

Output:

Total elements in the list [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
Contains All method will return true

Example 2

import java.util.LinkedList;
import java.util.List;
public class JavaListContainsAllExample2 {
public static void main(String[] args) {
        List<Integer> list= new LinkedList<>();
for (int i=0;i<11;i++){
list.add(i);
        }
System.out.println("Total elements in the list : "+list);
//returns an exception if the specified collection is null
Boolean bool=list.containsAll(null);
if (bool) {
System.out.println("Contains All method will return " + bool);
        }
else{
System.out.println("Contains All method will return " + bool);
        }
    }
}

Test it Now

Output:

Total elements in the list : [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
Exception in thread "main" java.lang.NullPointerException
	at java.util.AbstractCollection.containsAll(AbstractCollection.java:317)
	at com.javaTpoint.JavaListContainsAllExample2.main(JavaListContainsAllExample2.java:13)

Example 3

import java.util.LinkedList;
import java.util.List;
public class JavaListContainsAllExample3 {
public static void main(String[] args) {
        List<Integer> list= new LinkedList<>();
for (int i=0;i<11;i++){
list.add(i);
        }
System.out.println("Total elements in the list : "+list);
        List<Float> list1= new LinkedList<>();
for (Float i=0.0f;i<11;i++){
            list1.add(i);
        }
System.out.println("Total elements in the list1 : "+list1);

// returns a Boolean value ?true?,  if this list contains all the elements of the invoked collection.
Boolean bool=list.containsAll(list1);
if (bool) {
System.out.println("Contains All method will return " + bool);
        }
else{
System.out.println("Contains All method will return " + bool);
        }
    }
}

Test it Now

Output:

Total elements in the list : [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
Total elements in the list1 : [0.0, 1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 7.0, 8.0, 9.0, 10.0]
Contains All method will return false

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