What are the differences between a JTextField and a JFormattedTextField in Java?

AWTJavaObject Oriented ProgrammingProgrammingSwing

A JTextField can be used for plain text whereas a JFormattedTextField is a class that can extend JTextField and it can be used to set any format to the text that it contains phone numbers, e-mails, dates and etc.

JTextField

  • A JTextFeld is one of the most important components that allow the user to type an input text value in a single line format.
  • A JTextField can generate an ActionListener interface when we try to enter some input inside the text field and it can generate a CaretListener interface each time the caret (i.e. the cursor) changes position.
  • A JTextField can also generate a MouseListener and KeyListener interfaces.

Example

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class JTextFieldTest extends JFrame {
   JTextField jtf;
   public JTextFieldTest() {
      setTitle("JTextField Test");
      setLayout(new FlowLayout());
      jtf = new JTextField(15);
      add(jtf);
      jtf.addActionListener(new ActionListener() {
         public void actionPerformed (ActionEvent ae) {
            System.out.println("Event generated: " + jtf.getText());
         }
      });
      setSize(375, 250);
      setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
      setLocationRelativeTo(null);
      setVisible(true);
   }
   public static void main(String args[]) {
      new JTextFieldTest();
   }
}

Output

JFomattedTextField

  • A formatted text field is an instance of the class JFormattedTextField which is a direct subclass of JTextField.
  • A JFormattedTextField is like a normal text field except that is controls the validity of the characters the user type and it can be associated with a formatter that specifies the characters the user can enter.
  • A JFormattedTextField is a subclass of Format class to build a formatted text field. We can create a formatter, customize it if necessary. We can call the JFormattedTextField(Format format) constructor which takes an argument of type Format.
import java.awt.*;
import javax.swing.*;
import javax.swing.text.*;
public class JFormattedTextFieldTest extends JFrame {
   JFormattedTextField jftf;
   MaskFormatter mf;
   public JFormattedTextFieldTest() {
      setTitle("JFormattedTextField Test");
      setLayout(new FlowLayout());
      // A phone number formatter - (country code)-(area code)-(number)
      try {
         mf = new MaskFormatter("##-###-#######");
         mf.setPlaceholderCharacter('#');
         jftf = new JFormattedTextField(mf);
         jftf.setColumns(12);
      } catch(Exception e) {
         e.printStackTrace();
      }
      add(jftf);
      setSize(375, 250);
      setLocationRelativeTo(null);
      setDefaultCloseOperation(EXIT_ON_CLOSE);
      setVisible(true);
   }
   public static void main(String args[]) {
      new JFormattedTextFieldTest();
   }
}

Output


raja
Published on 15-Jul-2019 16:22:06
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