AWT TextArea Class

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Introduction

The TextArea control in AWT provide us multiline editor area. The user can type here as much as he wants. When the text in the text area become larger than the viewable area the scroll bar is automatically appears which help us to scroll the text up & down and right & left.

Class declaration

Following is the declaration for java.awt.TextArea class:

public class TextArea
   extends TextComponent

Field

Following are the fields for java.awt.TextArea class:

  • static int SCROLLBARS_BOTH -- Create and display both vertical and horizontal scrollbars.

  • static int SCROLLBARS_HORIZONTAL_ONLY -- Create and display horizontal scrollbar only.

  • static int SCROLLBARS_NONE -- Do not create or display any scrollbars for the text area.

  • static int SCROLLBARS_VERTICAL_ONLY -- Create and display vertical scrollbar only.

Class constructors

S.N.Constructor & Description
1TextArea()
Constructs a new text area with the empty string as text.
2TextArea(int rows, int columns)
Constructs a new text area with the specified number of rows and columns and the empty string as text.
3TextArea(String text)
Constructs a new text area with the specified text.
4TextArea(String text, int rows, int columns)
Constructs a new text area with the specified text, and with the specified number of rows and columns.
5TextArea(String text, int rows, int columns, int scrollbars)
Constructs a new text area with the specified text, and with the rows, columns, and scroll bar visibility as specified.

Class methods

S.N.Method & Description
1void addNotify()
Creates the TextArea's peer.
2void append(String str)
Appends the given text to the text area's current text.
3void appendText(String str)
Deprecated. As of JDK version 1.1, replaced by append(String).
4AccessibleContext getAccessibleContext()
Returns the AccessibleContext associated with this TextArea.
5int getColumns()
Returns the number of columns in this text area.
6Dimension getMinimumSize()
Determines the minimum size of this text area.
7Dimension getMinimumSize(int rows, int columns)
Determines the minimum size of a text area with the specified number of rows and columns.
8Dimension getPreferredSize()
Determines the preferred size of this text area.
9Dimension getPreferredSize(int rows, int columns)
Determines the preferred size of a text area with the specified number of rows and columns.
10int getRows()
Returns the number of rows in the text area.
11int getScrollbarVisibility()
Returns an enumerated value that indicates which scroll bars the text area uses.
12void insert(String str, int pos)
Inserts the specified text at the specified position in this text area.
13void insertText(String str, int pos)
Deprecated. As of JDK version 1.1, replaced by insert(String, int).
14Dimension minimumSize()
Deprecated. As of JDK version 1.1, replaced by getMinimumSize().
15Dimension minimumSize(int rows, int columns)
Deprecated. As of JDK version 1.1, replaced by getMinimumSize(int, int).
16protected String paramString()
Returns a string representing the state of this TextArea.
17Dimension preferredSize()
Deprecated. As of JDK version 1.1, replaced by getPreferredSize().
18Dimension preferredSize(int rows, int columns)
Deprecated. As of JDK version 1.1, replaced by getPreferredSize(int, int).
19void replaceRange(String str, int start, int end)
Replaces text between the indicated start and end positions with the specified replacement text.
20void replaceText(String str, int start, int end)
Deprecated. As of JDK version 1.1, replaced by replaceRange(String, int, int).
21void setColumns(int columns)
Sets the number of columns for this text area.
22void setRows(int rows)
Sets the number of rows for this text area.

Methods inherited

This class inherits methods from the following classes:

  • java.awt.TextComponent

  • java.awt.Component

  • java.lang.Object

TextArea Example

Create the following java program using any editor of your choice in say D:/ > AWT > com > tutorialspoint > gui >

AwtControlDemo.java
package com.tutorialspoint.gui;

import java.awt.*;
import java.awt.event.*;

public class AwtControlDemo {

   private Frame mainFrame;
   private Label headerLabel;
   private Label statusLabel;
   private Panel controlPanel;

   public AwtControlDemo(){
      prepareGUI();
   }

   public static void main(String[] args){
      AwtControlDemo  awtControlDemo = new AwtControlDemo();
      awtControlDemo.showTextAreaDemo();
   }

   private void prepareGUI(){
      mainFrame = new Frame("Java AWT Examples");
      mainFrame.setSize(400,400);
      mainFrame.setLayout(new GridLayout(3, 1));
      mainFrame.addWindowListener(new WindowAdapter() {
         public void windowClosing(WindowEvent windowEvent){
            System.exit(0);
         }        
      });    
      headerLabel = new Label();
      headerLabel.setAlignment(Label.CENTER);
      statusLabel = new Label();        
      statusLabel.setAlignment(Label.CENTER);
      statusLabel.setSize(350,100);

      controlPanel = new Panel();
      controlPanel.setLayout(new FlowLayout());

      mainFrame.add(headerLabel);
      mainFrame.add(controlPanel);
      mainFrame.add(statusLabel);
      mainFrame.setVisible(true);  
   }

   private void showTextAreaDemo(){
      headerLabel.setText("Control in action: TextArea"); 

      Label  commentlabel= new Label("Comments: ", Label.RIGHT);

      final TextArea commentTextArea = new TextArea("This is a AWT tutorial "
      +"to make GUI application in Java.",5,30);

      Button showButton = new Button("Show");

      showButton.addActionListener(new ActionListener() {
         public void actionPerformed(ActionEvent e) {     
            statusLabel.setText( commentTextArea.getText());        
         }
      }); 

      controlPanel.add(commentlabel);
      controlPanel.add(commentTextArea);        
      controlPanel.add(showButton);
      mainFrame.setVisible(true);  
   }
}

Compile the program using command prompt. Go to D:/ > AWT and type the following command.

D:\AWT>javac com\tutorialspoint\gui\AwtControlDemo.java

If no error comes that means compilation is successful. Run the program using following command.

D:\AWT>java com.tutorialspoint.gui.AwtControlDemo

Verify the following output

AWT TextArea

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