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The clear() method of java.util.AbstractList class is used to remove all of the elements from this list. The list will be empty after this call returns. Syntax:

public void clear()

Returns Value: This method does not return anything. Below are the examples to illustrate the clear() method. Example 1:

Java

// Java program to demonstrate
// clear() method
// for String value

import java.util.*;

public class GFG1 {
    public static void main(String[] argv)
        throws Exception
    {

        try {

            // Creating object of AbstractList<String>
            AbstractList<String>
                arrlist1 = new ArrayList<String>();

            // Populating arrlist1
            arrlist1.add("A");
            arrlist1.add("B");
            arrlist1.add("C");
            arrlist1.add("D");
            arrlist1.add("E");

            // print the ArrayList
            System.out.println("Original ArrayListlist : "
                               + arrlist1);

            // Removing all the elements
            // using clear() method
            arrlist1.clear();

            // print the new ArrayList
            System.out.println("New ArrayList : "
                               + arrlist1);
        }

        catch (NullPointerException e) {
            System.out.println("Exception thrown : "
                               + e);
        }
    }
}

Output:

Original ArrayListlist : [A, B, C, D, E]
New ArrayList : []

Example 2:

Java

// Java program to demonstrate
// clear() method
// for Integer value

import java.util.*;

public class GFG1 {
    public static void main(String[] argv)
        throws Exception
    {

        try {

            // Creating object of AbstractList<Integer>
            AbstractList<Integer>
                arrlist1 = new ArrayList<Integer>();

            // Populating arrlist1
            arrlist1.add(10);
            arrlist1.add(20);
            arrlist1.add(30);
            arrlist1.add(40);
            arrlist1.add(50);

            // print the ArrayList
            System.out.println("Original ArrayListlist : "
                               + arrlist1);

            // Removing all the elements
            // using clear() method
            arrlist1.clear();

            // print the new ArrayList
            System.out.println("New ArrayList : "
                               + arrlist1);
        }

        catch (NullPointerException e) {
            System.out.println("Exception thrown : " + e);
        }
    }
}

Output:

Original ArrayListlist : [10, 20, 30, 40, 50]
New ArrayList : []

AbstractList clear() method in Java with Examples

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