Properties propertyNames() in Java

propertyNames(): This method is available in java.util.Properties class of Java.

Syntax:

Enumeration<?> java.util.Properties.propertyNames()

This method returns an enumeration of all the keys in this property list, including distinct keys in the default property list if a key of the same name has not already been found from the main properties list.

Parameters: NA

Returns: an enumeration of all the keys in this property list, including the keys in the default property list.

Throws:

ClassCastException - if any key in this property list is not a string.

Approach

Java

import java.util.Enumeration;
import java.util.Properties;

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

        Properties properties = new Properties();

        properties.put("Hello", "World");
        properties.put("C++", "Program");
        properties.put("Java", "Program");
        Enumeration<?> enumeration = properties.propertyNames();

        while (enumeration.hasMoreElements()) {
            System.out.print(enumeration.nextElement() + " ");

        }

    }
}

Output:

Java C++ Hello