PasswordField in JavaFX

Introduction

Passwords are our computer's first line of defence against unwanted access. They are also used to protect our personal information. The stronger our password, the better our computer will be secured from hackers and unwanted software. We should use strong passwords for all accounts on our computers. However, we must also secure our credentials against shoulder surfing, which occurs when someone sees our passwords from behind. We also need to protect our credentials from screen scraping malware, which might be used to copy information displayed on a screen or window. 
This article will demonstrate how to create a PasswordField in JavaFX by utilising the PasswordField class of Java.

JavaFX PasswordField

JavaFX includes the PasswordField class. It is a Text field that conceals the characters that are typed. As a result, the user is not shown the entered characters. The user can insert a single line of unformatted text. As a result, multi-line input is not possible. Since the PasswordField in JavaFX is for users to input their password, the password field shows echo characters rather than the password itself for security reasons.
Like any other text field, a PasswordField in JavaFX triggers an action event when the user confirms that the text entry is finished, for example, by hitting the Enter button or clicking the login or sign-in button.

Uses of PasswordField

We can see the uses of PasswordField in JavaFX below.

• Used for security reasons: A password field does not show the characters that the user types. Instead, the field displays a character different from the one typed, such as an asterisk '*'. This is known as displaying echo characters.
• Greater Privacy: It prevents shoulder surfing. In simple words, PasswordField in JavaFX prevents nearby or adjacent viewers from reading the user's password over the user's shoulder. 
• Higher security: As another security precaution, a password field stores its value as an array of characters rather than as a string, thus helping from the risk of making the password easier to find. 
• Protection from malware: PasswordField in JavaFX protects us from screen scraping. The procedure of gathering screen displays information from one application and interpreting it so that another application could exhibit it.

Example

We will be going through the example of making a JFX PasswordField demonstrated below:

package application;
import javafx.application.Application;
import javafx.event.EventHandler;
import javafx.geometry.Insets;
import javafx.stage.Stage;
import javafx.scene.Node;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.control.PasswordField;
import javafx.scene.input.KeyCode;
import javafx.scene.input.KeyEvent;
import javafx.scene.layout.BorderPane;
import javafx.scene.layout.HBox;
import javafx.scene.control.Label;

public class Main extends Application {
	private BorderPane root;
	private Stage stage;
	private Scene scene;
	private Label lblPassword;
	private PasswordField password;
	private Button btnOk;
	private Label lblMessage;
	@Override
	public void start(Stage primaryStage) {
		try {
			primaryStage.setTitle("PasswordField Demo");
			BorderPane root = new BorderPane();
			lblPassword = new Label("Password:");
			password = new PasswordField();
			password.setPrefColumnCount(10);
			btnOk = new Button("OK");
			btnOk.setPrefSize(75, 25);
			lblMessage = new Label("Ready");
			
			//Add KeyEvent Handler to PasswordField
			password.onKeyPressedProperty().set(new EventHandler<KeyEvent>() {
				@Override
				public void handle(KeyEvent event) {
					if (event.getCode().equals(KeyCode.ENTER) || event.getCode().equals(KeyCode.TAB)) {
						if (password.getText().length() <4) {
							lblMessage.setText("Password must be at least 4 characters in length");
						}else {
							lblMessage.setText("You have entered password: " + password.getText());
							btnOk.requestFocus();
						}
					}
				}
			});
			root.setTop(createHBox(lblPassword, password, btnOk));
			root.setBottom(createHBox(lblMessage));
				Scene scene = new Scene(root,400,400);
			scene.getStylesheets().add(getClass().getResource("application.css").toExternalForm());
			primaryStage.setScene(scene);
			primaryStage.show();
		} catch(Exception e) {
			e.printStackTrace();
		}
	}
	public static void main(String[] args) {
		launch(args);
	}
	public HBox createHBox(Node... children) {
		HBox hbox = new HBox(children);
		hbox.setPadding(new Insets(10));
		hbox.setSpacing(10);
		return hbox;
	}
}

You can also try this code with Online Java Compiler

Run Code

Output

We will be getting an output showing that the password field is ready to take input. 

We will then enter the password in the field shown below.

We saw that the message came as "Password must be at least 4 characters in length", as we have set the password length to be more than 4 for a strong password. We will then try to enter the password in the correct format.

Now we can see that the password got accepted as it meets the criteria of having more than four characters. At the bottom of the box, we can see that the password entered has been displayed. 
Therefore, with this, we covered a simple example of PasswordField in JavaFX. 

[Note: While making a PasswordField JavaFX, make sure to avoid showing up your password as given in the example.]

Frequently Asked Questions

What is the difference between a TextField and a PasswordField?

TextField - This is used to allow the user to enter text, and the text that the user writes will be shown as it is typed.

PasswordField - This field also accepts user input. It does, however, use some symbols or characters to mask/disguise the text that is entered.

Which package is used to create a text node in JavaFX?

To create a text node in JavaFX, we have to use the package javafx.scene.text.

What are the three JavaFX application life cycle methods?

In JavaFX applications, the three life cycle methods are: Init(), Stop(), and Start().