The keySet() method of Properties class is used to create a set out of the key elements contained in the Properties. It basically returns a set view of the keys or we can create a new set and store the key elements in them.
Syntax:
public Set keySet()
Parameters: This method accepts no parameters
Returns: This method returns a Set view of the keys contained in this Properties object.
Below programs show the implementation of int keySet() method.
Program 1:
// Java code to show the implementation of// keySet() method import java.util.*;public class GfG { // Main method public static void main(String[] args) { // Create a properties and add some values Properties properties = new Properties(); properties.put("Pen", 10); properties.put("Book", 500); properties.put("Clothes", 400); properties.put("Mobile", 5000); // Print Properties details System.out.println("Properties: " + properties.toString()); System.out.println("keySet: " + properties.keySet()); }} |
Properties: {Book=500, Mobile=5000, Pen=10, Clothes=400}
keySet: [Book, Mobile, Pen, Clothes]
Program 2:
// Java program to demonstrate// keySet() method. import java.util.*; public class GFG { // Main method public static void main(String[] args) { // Create a properties and add some values Properties properties = new Properties(); // Inserting elements into the properties properties.put("Geeks", 10); properties.put("4", 15); properties.put("Geeks", 20); properties.put("Welcomes", 25); properties.put("You", 30); // Print Properties details System.out.println("Current Properties: " + properties.toString()); System.out.println("keySet: " + properties.keySet()); }} |
Current Properties: {You=30, Welcomes=25, 4=15, Geeks=20}
keySet: [You, Welcomes, 4, Geeks]
References: https://docs.oracle.com/javase/9/docs/api/java/util/Properties.html#keySet–
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