Java Swing | JTextArea - GeeksforGeeks

JTextArea is a part of java Swing package . It represents a multi line area that displays text. It is used to edit the text .
JTextArea inherits JComponent class. The text in JTextArea can be set to different available fonts and can be appended to new text . A text area can be customized to the need of user .

Constructors of JTextArea are:

JTextArea() : constructs a new blank text area .
JTextArea(String s) : constructs a new text area with a given initial text.
JTextArea(int row, int column) : constructs a new text area with a given number of rows and columns.
JTextArea(String s, int row, int column) : constructs a new text area with a given number of rows and columns and a given initial text.

Commonly used methods :

append(String s) : appends the given string to the text of the text area.
getLineCount() : get number of lines in the text of text area.
setFont(Font f) : sets the font of text area to the given font.
setColumns(int c) : sets the number of columns of the text area to given integer.
setRows(int r) : sets the number of rows of the text area to given integer.
getColumns() : get the number of columns of text area.
getRows() : get the number of rows of text area.

1. Program to create a simple JTextArea

// Java Program to create a simple JTextArea 
import java.awt.event.*; 
import java.awt.*; 
import javax.swing.*; 
class text extends JFrame implements ActionListener { 
  
    // JFrame 
    static JFrame f; 
  
    // JButton 
    static JButton b; 
  
    // label to display text 
    static JLabel l; 
  
    // text area 
    static JTextArea jt; 
  
    // default constructor 
    text() 
    { 
    } 
  
    // main class 
    public static void main(String[] args) 
    { 
        // create a new frame to store text field and button 
        f = new JFrame("textfield"); 
  
        // create a label to display text 
        l = new JLabel("nothing entered"); 
  
        // create a new button 
        b = new JButton("submit"); 
  
        // create a object of the text class 
        text te = new text(); 
  
        // addActionListener to button 
        b.addActionListener(te); 
  
        // create a text area, specifying the rows and columns 
        jt = new JTextArea(10, 10); 
  
        JPanel p = new JPanel(); 
  
        // add the text area and button to panel 
        p.add(jt); 
        p.add(b); 
        p.add(l); 
  
        f.add(p); 
        // set the size of frame 
        f.setSize(300, 300); 
  
        f.show(); 
    } 
  
    // if the button is pressed 
    public void actionPerformed(ActionEvent e) 
    { 
        String s = e.getActionCommand(); 
        if (s.equals("submit")) { 
            // set the text of the label to the text of the field 
            l.setText(jt.getText()); 
        } 
    } 
} 

Output:

2. Program to create a JTextArea and set a initial text and add buttons to change the font of text area.

// Java Program Program to create a JTextArea and 
// set a initial text and add buttons to change 
// the font of text area. 
import java.awt.event.*; 
import java.awt.*; 
import javax.swing.*; 
class text11 extends JFrame implements ActionListener { 
  
    // JFrame 
    static JFrame f; 
  
    // JButton 
    static JButton b, b1, b2, b3; 
  
    // label to display text 
    static JLabel l, l1; 
  
    // text area 
    static JTextArea jt; 
  
    // default constructor 
    text11() 
    { 
    } 
  
    // main class 
    public static void main(String[] args) 
    { 
        // create a new frame to store text field and button 
        f = new JFrame("textfield"); 
  
        // create a label to display text 
        l = new JLabel("nothing entered"); 
        l1 = new JLabel("0 lines"); 
  
        // create a new buttons 
        b = new JButton("submit"); 
        b1 = new JButton("plain"); 
        b2 = new JButton("italic"); 
        b3 = new JButton("bold"); 
  
        // create a object of the text class 
        text11 te = new text11(); 
  
        // addActionListener to button 
        b.addActionListener(te); 
        b1.addActionListener(te); 
        b2.addActionListener(te); 
        b3.addActionListener(te); 
  
        // create a text area, specifying the rows and columns 
        jt = new JTextArea("please write something ", 10, 10); 
  
        JPanel p = new JPanel(); 
  
        // add the text area and button to panel 
        p.add(jt); 
        p.add(b); 
        p.add(b1); 
        p.add(b2); 
        p.add(b3); 
        p.add(l); 
        p.add(l1); 
  
        f.add(p); 
        // set the size of frame 
        f.setSize(300, 300); 
  
        f.show(); 
    } 
  
    // if the button is pressed 
    public void actionPerformed(ActionEvent e) 
    { 
        String s = e.getActionCommand(); 
        if (s.equals("submit")) { 
            // set the text of the label to the text of the field 
            l.setText(jt.getText() + ", "); 
            l1.setText(jt.getLineCount() + " lines"); 
        } 
        else if (s.equals("bold")) { 
  
            // set bold font 
            Font f = new Font("Serif", Font.BOLD, 15); 
            jt.setFont(f); 
        } 
        else if (s.equals("italic")) { 
            // set italic font 
            Font f = new Font("Serif", Font.ITALIC, 15); 
            jt.setFont(f); 
        } 
        else if (s.equals("plain")) { 
            // set plain font 
            Font f = new Font("Serif", Font.PLAIN, 15); 
            jt.setFont(f); 
        } 
    } 
} 

Output :

Note : The following program might mot run in an online compiler please use an offline IDE

Attention reader! Don’t stop learning now. Get hold of all the important Java and Collections concepts with the Fundamentals of Java and Java Collections Course at a student-friendly price and become industry ready.

My Personal Notes

Recommended Posts: