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Java TreeMap clear() Method with Example

TreeMap Class clear() method: Here, we are going to learn about the clear() method of TreeMap Class with its syntax and example.
Submitted by Preeti Jain, on February 19, 2020

TreeMap Class clear() method

• clear() method is available in java.util package.
• clear() method is used to clear all of the existing mappings from this TreeMap.
• clear() method is a non-static method, it is accessible with the class object only and if we try to access the method with the class name then we will get an error.
• clear() method does not throw an exception at the time of removing objects from this TreeMap.

Syntax:

    public void clear();

Parameter(s):

• It does not accept any parameter.

Return value:

The return type of the method is void, it returns nothing.

Example:

// Java program to demonstrate the example 
// of void clear() method of TreeMap 

import java.util.*;

public class ClearOfTreeMap {
    public static void main(String[] args) {
        // Instantiates a TreeMap object
        NavigableMap < Integer, String > tree_map = new TreeMap < Integer, String > ();

        // By using put() method is to add
        //key-value pairs in a TreeMap
        tree_map.put(10, "C");
        tree_map.put(20, "C++");
        tree_map.put(50, "JAVA");
        tree_map.put(40, "PHP");
        tree_map.put(30, "SFDC");

        //Display TreeMap
        System.out.println("TreeMap: " + tree_map);

        // By using clear() method is
        // to remove the mappings in this TreeMap
        tree_map.clear();

        System.out.print("tree_map.clear(): ");
        System.out.println(tree_map);
    }
}

Output

TreeMap: {10=C, 20=C++, 30=SFDC, 40=PHP, 50=JAVA}
tree_map.clear(): {}