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The clear() method of CopyOnWriteArraySet erases all the elements in the Set. The size of the Set becomes zero after the function is called. Syntax:

public void clear()

Return Value: The function does not returns anything. Below programs illustrate the above function: Program 1:

Java

// Java Program to illustrate the CopyOnWriteArraySet
// clear() method in Java

import java.util.concurrent.CopyOnWriteArraySet;
import java.util.*;

public class GFG {
    public static void main(String[] args)
    {

        // create object of CopyOnWriteArraySet
        CopyOnWriteArraySet<Integer> ArrSet
            = new CopyOnWriteArraySet<Integer>();

        // Add elements
        ArrSet.add(32);
        ArrSet.add(67);
        ArrSet.add(98);
        ArrSet.add(98);

        // print CopyOnWriteArraySet
        System.out.println("CopyOnWriteArraySet: "
                           + ArrSet);

        // Clear the CopyOnWriteArraySet
        // Using clear() method
        ArrSet.clear();

        System.out.println("\nCopyOnWriteArraySet cleared\n");

        // Print the updated CopyOnWriteArraySet
        System.out.println("Updated CopyOnWriteArraySet: "
                           + ArrSet);
    }
}

Output:

CopyOnWriteArraySet: [32, 67, 98]

CopyOnWriteArraySet cleared

Updated CopyOnWriteArraySet: []

Program 2:

Java

// Java Program to illustrate the CopyOnWriteArraySet
// clear() method in Java

import java.util.concurrent.CopyOnWriteArraySet;
import java.util.*;

public class GFG {
    public static void main(String[] args)
    {

        // create object of CopyOnWriteArraySet
        CopyOnWriteArraySet<String> ArrSet
            = new CopyOnWriteArraySet<String>();

        // Add elements
        ArrSet.add("gopal");
        ArrSet.add("gfg");
        ArrSet.add("jgec");
        ArrSet.add("jgec");

        // print CopyOnWriteArraySet
        System.out.println("CopyOnWriteArraySet: "
                           + ArrSet);

        // Clear the CopyOnWriteArraySet
        // Using clear() method
        ArrSet.clear();

        System.out.println("\nCopyOnWriteArraySet cleared\n");

        // Print the updated CopyOnWriteArraySet
        System.out.println("Updated CopyOnWriteArraySet: "
                           + ArrSet);
    }
}

Output:

CopyOnWriteArraySet: [gopal, gfg, jgec]

CopyOnWriteArraySet cleared

Updated CopyOnWriteArraySet: []

Reference: https://docs.oracle.com/javase/8/docs/api/java/util/concurrent/CopyOnWriteArraySet.html#clear--

CopyOnWriteArraySet clear() method in Java

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