Java by API/javax.swing/JTextArea

JTextArea: addCaretListener(CaretListener listener)

   <source lang="java">

import java.awt.BorderLayout; import javax.swing.JFrame; import javax.swing.JScrollPane; import javax.swing.JTextArea; import javax.swing.event.CaretEvent; import javax.swing.event.CaretListener; public class Main {

 public static void main(String args[]) {
   JFrame frame = new JFrame("Caret Example");
   frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
   JTextArea textArea = new JTextArea();
   JScrollPane scrollPane = new JScrollPane(textArea);
   frame.add(scrollPane, BorderLayout.CENTER);
   
   CaretListener listener = new CaretListener() {
     public void caretUpdate(CaretEvent caretEvent) {
       System.out.println("Dot: "+ caretEvent.getDot());
       System.out.println("Mark: "+caretEvent.getMark());
     }
   };
   textArea.addCaretListener(listener);
   frame.setSize(250, 150);
   frame.setVisible(true);
 }

}

 </source>
   
  
 
  

JTextArea: addUndoableEditListener(UndoableEditListener lis)

   <source lang="java">

import java.awt.BorderLayout; import java.awt.ruponent; import java.awt.Container; import java.awt.event.ActionEvent; import javax.swing.AbstractAction; import javax.swing.JButton; import javax.swing.JFrame; import javax.swing.JOptionPane; import javax.swing.JScrollPane; import javax.swing.JTextArea; import javax.swing.JToolBar; import javax.swing.UIManager; import javax.swing.undo.CannotUndoException; import javax.swing.undo.UndoManager; public class MainClass {

 public static void main(final String args[]) {
   JFrame frame = new JFrame("Undo Sample");
   frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
   JTextArea textArea = new JTextArea();
   JScrollPane scrollPane = new JScrollPane(textArea);
   UndoManager manager = new UndoManager();
   textArea.getDocument().addUndoableEditListener(manager);
   JToolBar toolbar = new JToolBar();
   JButton undoButton = new JButton(new UndoAction(manager, (String) UIManager
       .get("AbstractUndoableEdit.undoText")));
   toolbar.add(undoButton);
   Container content = frame.getContentPane();
   content.add(toolbar, BorderLayout.NORTH);
   content.add(scrollPane, BorderLayout.CENTER);
   frame.setSize(300, 150);
   frame.setVisible(true);
 }

} abstract class UndoRedoAction extends AbstractAction {

 UndoManager undoManager = new UndoManager();
 String errorMessage = "Cannot undo";
 String errorTitle = "Undo Problem";
 protected UndoRedoAction(UndoManager manager, String name) {
   super(name);
   undoManager = manager;
 }
 public void setErrorMessage(String newValue) {
   errorMessage = newValue;
 }
 public void setErrorTitle(String newValue) {
   errorTitle = newValue;
 }
 protected void showMessage(Object source) {
   if (source instanceof Component) {
     JOptionPane.showMessageDialog((Component) source, errorMessage, errorTitle,
         JOptionPane.WARNING_MESSAGE);
   } else {
     System.err.println(errorMessage);
   }
 }

} class UndoAction extends UndoRedoAction {

 public UndoAction(UndoManager manager, String name) {
   super(manager, name);
   setErrorMessage("Cannot undo");
   setErrorTitle("Undo Problem");
 }
 public void actionPerformed(ActionEvent actionEvent) {
   try {
     undoManager.undo();
   } catch (CannotUndoException cannotUndoException) {
     showMessage(actionEvent.getSource());
   }
 }

}

 </source>
   
  
 
  

JTextArea: append(String str)

   <source lang="java">

import javax.swing.JTextArea; public class Main {

 public static void main(String[] argv) {
   JTextArea ta = new JTextArea("Initial Text");
   ta.append("some text");
 }

}

 </source>
   
  
 
  

JTextArea: getActionMap()

   <source lang="java">

import java.awt.ruponent; import java.awt.event.ActionEvent; import javax.swing.AbstractAction; import javax.swing.Action; import javax.swing.JTextArea; public class Main {

 public static void main(String[] argv) throws Exception {
   JTextArea component = new JTextArea();
   NextFocusAction nextFocusAction = new NextFocusAction();
   PrevFocusAction prevFocusAction = new PrevFocusAction();
   
   component.getActionMap().put(nextFocusAction.getValue(Action.NAME), nextFocusAction);
   component.getActionMap().put(prevFocusAction.getValue(Action.NAME), prevFocusAction);
 }

} class NextFocusAction extends AbstractAction{

 public NextFocusAction(){
   super("Move Focus Forwards");
 }
 public void actionPerformed(ActionEvent evt) {
   ((Component) evt.getSource()).transferFocus();
 }

} class PrevFocusAction extends AbstractAction {

 public PrevFocusAction(){
   super("Move Focus Backwards");
 }
 public void actionPerformed(ActionEvent evt) {
   ((Component) evt.getSource()).transferFocusBackward();
 }

}

 </source>
   
  
 
  

JTextArea: getActions()

   <source lang="java">

import javax.swing.*; import javax.swing.text.*; import java.util.Hashtable; import java.awt.event.*; import java.awt.BorderLayout; public class KeymapExample {

 public static void main(String[] args) {
   JTextArea area = new JTextArea(6, 32);
   Keymap parent = area.getKeymap();
   Keymap newmap = JTextComponent.addKeymap("KeymapExampleMap", parent);
   KeyStroke u = KeyStroke.getKeyStroke(KeyEvent.VK_U, InputEvent.CTRL_MASK);
   Action actionU = new UpWord(); 
   newmap.addActionForKeyStroke(u, actionU);
   Action actionList[] = area.getActions();
   Hashtable lookup = new Hashtable();
   for (int j=0; j < actionList.length; j+=1)
     lookup.put(actionList[j].getValue(Action.NAME), actionList[j]);
   KeyStroke L = KeyStroke.getKeyStroke(KeyEvent.VK_L, InputEvent.CTRL_MASK);
   Action actionL = (Action)lookup.get(DefaultEditorKit.selectLineAction);
   newmap.addActionForKeyStroke(L, actionL);
   KeyStroke W = KeyStroke.getKeyStroke(KeyEvent.VK_W, InputEvent.CTRL_MASK);
   Action actionW = (Action)lookup.get(DefaultEditorKit.selectWordAction);
   newmap.addActionForKeyStroke(W, actionW);
   area.setKeymap(newmap);
   JFrame f = new JFrame("KeymapExample");
   f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
   f.getContentPane().add(new JScrollPane(area), BorderLayout.CENTER);
   area.setText("www.\n jexp \n .ru.");
   f.pack();
   f.setVisible(true);
 }
 public static class UpWord extends TextAction {
   public UpWord() {
     super("uppercase-word-action");
   }
   public void actionPerformed(ActionEvent e) {
     JTextComponent comp = getTextComponent(e);
     if (comp == null) return;
     Document doc = comp.getDocument();
     int start = comp.getSelectionStart();
     int end = comp.getSelectionEnd();
     try {
       int left = javax.swing.text.Utilities.getWordStart(comp, start);
       int right = javax.swing.text.Utilities.getWordEnd(comp, end);
       String word = doc.getText(left, right-left);
       doc.remove(left, right-left);
       doc.insertString(left, word.toUpperCase(), null);
       comp.setSelectionStart(start); // restore previous position/selection
       comp.setSelectionEnd(end);
     } catch (BadLocationException ble) { return; }
   }
 }

}

 </source>
   
  
 
  

JTextArea: getCaretPosition()

   <source lang="java">

import java.awt.Color; import javax.swing.JTextArea; import javax.swing.text.JTextComponent; public class Main {

 public static void main(String[] argv) throws Exception {
   JTextComponent c = new JTextArea();
   c.getCaretPosition();
   if (c.getCaretPosition() < c.getDocument().getLength()) {
     char ch = c.getText(c.getCaretPosition(), 1).charAt(0);
   }
   // Set the caret color
   c.setCaretColor(Color.red);
 }

}

 </source>
   
  
 
  

JTextArea: getDocument()

   <source lang="java">

import java.awt.Container; import javax.swing.BoxLayout; import javax.swing.JFrame; import javax.swing.JScrollPane; import javax.swing.JTextArea; import javax.swing.text.Document; public class MainClass {

 public static void main(String args[]) {
   JFrame frame = new JFrame("Sharing Sample");
   frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
   Container content = frame.getContentPane();
   JTextArea textarea1 = new JTextArea();
   Document document = textarea1.getDocument();
   JTextArea textarea2 = new JTextArea(document);
   JTextArea textarea3 = new JTextArea(document);
   content.setLayout(new BoxLayout(content, BoxLayout.Y_AXIS));
   content.add(new JScrollPane(textarea1));
   content.add(new JScrollPane(textarea2));
   content.add(new JScrollPane(textarea3));
   frame.setSize(300, 400);
   frame.setVisible(true);
 }

}

 </source>
   
  
 
  

JTextArea: getFont()

   <source lang="java">

import java.awt.Font; import javax.swing.JTextArea; public class Main {

 public static void main(String[] argv) {
   JTextArea textarea = new JTextArea();
   // Get the default tab size
   int tabSize = textarea.getTabSize(); // 8
   // Change the tab size
   tabSize = 4;
   textarea.setTabSize(tabSize);
   Font font = textarea.getFont();
   System.out.println(font);
 }

}

 </source>
   
  
 
  

JTextArea: getHighlighter()

   <source lang="java">

import java.awt.BorderLayout; import javax.swing.JFrame; import javax.swing.JScrollPane; import javax.swing.JTextArea; import javax.swing.text.DefaultHighlighter; import javax.swing.text.Highlighter; public class Main {

 public static void main(String args[]) throws Exception {
   JFrame frame = new JFrame("MultiHighlight");
   frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
   JTextArea comp = new JTextArea(5, 20);
   comp.setText("this is a test");
   frame.getContentPane().add(new JScrollPane(comp), BorderLayout.CENTER);
   String charsToHighlight = "a";
   Highlighter h = comp.getHighlighter();
   h.removeAllHighlights();
   String text = comp.getText().toUpperCase();
   for (int j = 0; j < text.length(); j += 1) {
     char ch = text.charAt(j);
     if (charsToHighlight.indexOf(ch) >= 0)
       h.addHighlight(j, j + 1, DefaultHighlighter.DefaultPainter);
   }
   frame.pack();
   frame.setVisible(true);
 }

}

 </source>
   
  
 
  

JTextArea: getKeymap()

   <source lang="java">

import javax.swing.*; import javax.swing.text.*; import java.util.Hashtable; import java.awt.event.*; import java.awt.BorderLayout; public class KeymapExample {

 public static void main(String[] args) {
   JTextArea area = new JTextArea(6, 32);
   Keymap parent = area.getKeymap();
   Keymap newmap = JTextComponent.addKeymap("KeymapExampleMap", parent);
   KeyStroke u = KeyStroke.getKeyStroke(KeyEvent.VK_U, InputEvent.CTRL_MASK);
   Action actionU = new UpWord(); 
   newmap.addActionForKeyStroke(u, actionU);
   Action actionList[] = area.getActions();
   Hashtable lookup = new Hashtable();
   for (int j=0; j < actionList.length; j+=1)
     lookup.put(actionList[j].getValue(Action.NAME), actionList[j]);
   KeyStroke L = KeyStroke.getKeyStroke(KeyEvent.VK_L, InputEvent.CTRL_MASK);
   Action actionL = (Action)lookup.get(DefaultEditorKit.selectLineAction);
   newmap.addActionForKeyStroke(L, actionL);
   KeyStroke W = KeyStroke.getKeyStroke(KeyEvent.VK_W, InputEvent.CTRL_MASK);
   Action actionW = (Action)lookup.get(DefaultEditorKit.selectWordAction);
   newmap.addActionForKeyStroke(W, actionW);
   area.setKeymap(newmap);
   JFrame f = new JFrame("KeymapExample");
   f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
   f.getContentPane().add(new JScrollPane(area), BorderLayout.CENTER);
   area.setText("www.\n jexp \n .ru.");
   f.pack();
   f.setVisible(true);
 }
 public static class UpWord extends TextAction {
   public UpWord() {
     super("uppercase-word-action");
   }
   public void actionPerformed(ActionEvent e) {
     JTextComponent comp = getTextComponent(e);
     if (comp == null) return;
     Document doc = comp.getDocument();
     int start = comp.getSelectionStart();
     int end = comp.getSelectionEnd();
     try {
       int left = javax.swing.text.Utilities.getWordStart(comp, start);
       int right = javax.swing.text.Utilities.getWordEnd(comp, end);
       String word = doc.getText(left, right-left);
       doc.remove(left, right-left);
       doc.insertString(left, word.toUpperCase(), null);
       comp.setSelectionStart(start); // restore previous position/selection
       comp.setSelectionEnd(end);
     } catch (BadLocationException ble) { return; }
   }
 }

}

 </source>
   
  
 
  

JTextArea: getLineCount()

   <source lang="java">

/*line 0 starts at 0, ends at 5 line 1 starts at 5, ends at 12 line 2 starts at 12, ends at 16 offset 0 is on line 0 offset 1 is on line 0 offset 2 is on line 0 offset 3 is on line 0 offset 4 is on line 0 offset 5 is on line 1 offset 6 is on line 1 offset 7 is on line 1 offset 8 is on line 1 offset 9 is on line 1 offset 10 is on line 1 offset 11 is on line 1 offset 12 is on line 2 offset 13 is on line 2 offset 14 is on line 2 offset 15 is on line 2 offset 16 is on line 2 offset 17 is on javax.swing.text.BadLocationException: Can"t translate offset to line

• /

import javax.swing.JFrame; import javax.swing.JScrollPane; import javax.swing.JTextArea; import javax.swing.text.BadLocationException; public class MainClass {

 public static void main(String[] args) {
   JTextArea ta = new JTextArea();
   ta.setLineWrap(true);
   ta.setWrapStyleWord(true);
   JScrollPane scroll = new JScrollPane(ta);
   ta.append("www.\n");
   ta.append("jexp\n");
   ta.append(".ru");
   try {
     for (int n = 0; n < ta.getLineCount(); n += 1)
       System.out.println("line " + n + " starts at " + ta.getLineStartOffset(n) + ", ends at "
           + ta.getLineEndOffset(n));
     System.out.println();
     int n = 0;
     while (true) {
       System.out.print("offset " + n + " is on ");
       System.out.println("line " + ta.getLineOfOffset(n));
       n += 1;
     }
   } catch (BadLocationException ex) {
     System.out.println(ex);
   }
   JFrame f = new JFrame();
   f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
   f.getContentPane().add(scroll, java.awt.BorderLayout.CENTER);
   f.setSize(150, 150);
   f.setVisible(true);
 }

}

 </source>
   
  
 
  

JTextArea: getLineEndOffset(int line)

   <source lang="java">

/*line 0 starts at 0, ends at 5 line 1 starts at 5, ends at 12 line 2 starts at 12, ends at 16 offset 0 is on line 0 offset 1 is on line 0 offset 2 is on line 0 offset 3 is on line 0 offset 4 is on line 0 offset 5 is on line 1 offset 6 is on line 1 offset 7 is on line 1 offset 8 is on line 1 offset 9 is on line 1 offset 10 is on line 1 offset 11 is on line 1 offset 12 is on line 2 offset 13 is on line 2 offset 14 is on line 2 offset 15 is on line 2 offset 16 is on line 2 offset 17 is on javax.swing.text.BadLocationException: Can"t translate offset to line

• /

import javax.swing.JFrame; import javax.swing.JScrollPane; import javax.swing.JTextArea; import javax.swing.text.BadLocationException; public class MainClass {

 public static void main(String[] args) {
   JTextArea ta = new JTextArea();
   ta.setLineWrap(true);
   ta.setWrapStyleWord(true);
   JScrollPane scroll = new JScrollPane(ta);
   ta.append("www.\n");
   ta.append("jexp\n");
   ta.append(".ru");
   try {
     for (int n = 0; n < ta.getLineCount(); n += 1)
       System.out.println("line " + n + " starts at " + ta.getLineStartOffset(n) + ", ends at "
           + ta.getLineEndOffset(n));
     System.out.println();
     int n = 0;
     while (true) {
       System.out.print("offset " + n + " is on ");
       System.out.println("line " + ta.getLineOfOffset(n));
       n += 1;
     }
   } catch (BadLocationException ex) {
     System.out.println(ex);
   }
   JFrame f = new JFrame();
   f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
   f.getContentPane().add(scroll, java.awt.BorderLayout.CENTER);
   f.setSize(150, 150);
   f.setVisible(true);
 }

}

 </source>
   
  
 
  

JTextArea.getLineOfOffset(int offset)

   <source lang="java">

/*line 0 starts at 0, ends at 5 line 1 starts at 5, ends at 12 line 2 starts at 12, ends at 16 offset 0 is on line 0 offset 1 is on line 0 offset 2 is on line 0 offset 3 is on line 0 offset 4 is on line 0 offset 5 is on line 1 offset 6 is on line 1 offset 7 is on line 1 offset 8 is on line 1 offset 9 is on line 1 offset 10 is on line 1 offset 11 is on line 1 offset 12 is on line 2 offset 13 is on line 2 offset 14 is on line 2 offset 15 is on line 2 offset 16 is on line 2 offset 17 is on javax.swing.text.BadLocationException: Can"t translate offset to line

• /

import javax.swing.JFrame; import javax.swing.JScrollPane; import javax.swing.JTextArea; import javax.swing.text.BadLocationException; public class MainClass {

 public static void main(String[] args) {
   JTextArea ta = new JTextArea();
   ta.setLineWrap(true);
   ta.setWrapStyleWord(true);
   JScrollPane scroll = new JScrollPane(ta);
   ta.append("www.\n");
   ta.append("jexp\n");
   ta.append(".ru");
   try {
     for (int n = 0; n < ta.getLineCount(); n += 1)
       System.out.println("line " + n + " starts at " + ta.getLineStartOffset(n) + ", ends at "
           + ta.getLineEndOffset(n));
     System.out.println();
     int n = 0;
     while (true) {
       System.out.print("offset " + n + " is on ");
       System.out.println("line " + ta.getLineOfOffset(n));
       n += 1;
     }
   } catch (BadLocationException ex) {
     System.out.println(ex);
   }
   JFrame f = new JFrame();
   f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
   f.getContentPane().add(scroll, java.awt.BorderLayout.CENTER);
   f.setSize(150, 150);
   f.setVisible(true);
 }

}

 </source>
   
  
 
  

JTextArea: getLineStartOffset(int line)

   <source lang="java">

/*line 0 starts at 0, ends at 5 line 1 starts at 5, ends at 12 line 2 starts at 12, ends at 16 offset 0 is on line 0 offset 1 is on line 0 offset 2 is on line 0 offset 3 is on line 0 offset 4 is on line 0 offset 5 is on line 1 offset 6 is on line 1 offset 7 is on line 1 offset 8 is on line 1 offset 9 is on line 1 offset 10 is on line 1 offset 11 is on line 1 offset 12 is on line 2 offset 13 is on line 2 offset 14 is on line 2 offset 15 is on line 2 offset 16 is on line 2 offset 17 is on javax.swing.text.BadLocationException: Can"t translate offset to line

• /

import javax.swing.JFrame; import javax.swing.JScrollPane; import javax.swing.JTextArea; import javax.swing.text.BadLocationException; public class MainClass {

 public static void main(String[] args) {
   JTextArea ta = new JTextArea();
   ta.setLineWrap(true);
   ta.setWrapStyleWord(true);
   JScrollPane scroll = new JScrollPane(ta);
   ta.append("www.\n");
   ta.append("jexp\n");
   ta.append(".ru");
   try {
     for (int n = 0; n < ta.getLineCount(); n += 1)
       System.out.println("line " + n + " starts at " + ta.getLineStartOffset(n) + ", ends at "
           + ta.getLineEndOffset(n));
     System.out.println();
     int n = 0;
     while (true) {
       System.out.print("offset " + n + " is on ");
       System.out.println("line " + ta.getLineOfOffset(n));
       n += 1;
     }
   } catch (BadLocationException ex) {
     System.out.println(ex);
   }
   JFrame f = new JFrame();
   f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
   f.getContentPane().add(scroll, java.awt.BorderLayout.CENTER);
   f.setSize(150, 150);
   f.setVisible(true);
 }

}

 </source>
   
  
 
  

JTextArea: insert(String str, int pos)

   <source lang="java">

import javax.swing.JTextArea; public class Main {

 public static void main(String[] argv) {
   JTextArea ta = new JTextArea("Initial Text");
   int pos = 5;
   ta.insert("some text", pos);
 }

}

 </source>
   
  
 
  

JTextArea: isManagingFocus()

   <source lang="java">

import java.awt.Container; import java.awt.GridLayout; import javax.swing.JFrame; import javax.swing.JScrollPane; import javax.swing.JTextArea; public class Main {

 public static void main(String args[]) {
   String title = (args.length == 0 ? "TextArea Example" : args[0]);
   JFrame frame = new JFrame(title);
   Container content = frame.getContentPane();
   content.setLayout(new GridLayout(0, 2));
   JTextArea leftTextArea = new JTextArea();
   content.add(leftTextArea);
   leftTextArea.paste();
   JTextArea rightTextArea = new JTextArea() {
     public boolean isManagingFocus() {
       return false;
     }
   };
   rightTextArea.paste();
   JScrollPane rightPane = new JScrollPane(rightTextArea);
   content.add(rightPane);
   frame.setSize(250, 150);
   frame.setVisible(true);
 }

}

 </source>
   
  
 
  

JTextArea: paste()

   <source lang="java">

import javax.swing.JFrame; import javax.swing.JTextArea; public class MainClass {

 public static void main(final String args[]) {
   JFrame frame = new JFrame();
   frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
   JTextArea leftTextArea = new JTextArea();
   frame.add(leftTextArea);
   leftTextArea.paste();
   frame.setSize(250, 150);
   frame.setVisible(true);
 }

}

 </source>
   
  
 
  

JTextArea: read(Reader in, Object desc)

   <source lang="java">

import java.awt.BorderLayout; import java.io.FileReader; import java.io.IOException; import javax.swing.JFrame; import javax.swing.JTextField; public class MainClass {

 public static void main(String args[]) throws Exception {
   JFrame frame = new JFrame();
   frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
   JTextField nameTextField = new JTextField();
   frame.add(nameTextField, BorderLayout.NORTH);
   
   FileReader reader = null;
   try {
     reader = new FileReader("fileName.txt");
     nameTextField.read(reader, "fileName.txt");
   } catch (IOException exception) {
     System.err.println("Load oops");
     exception.printStackTrace();
   } finally {
     if (reader != null) {
       try {
         reader.close();
       } catch (IOException exception) {
         System.err.println("Error closing reader");
         exception.printStackTrace();
       }
     }
   }
   
   frame.setSize(250, 100);
   frame.setVisible(true);
 }

}

 </source>
   
  
 
  

JTextArea: replaceRange(String str, int start, int end)

   <source lang="java">

import javax.swing.JTextArea; public class Main {

 public static void main(String[] argv) {
   JTextArea ta = new JTextArea("Initial Text");
   int start = 0;
   int end = 5;
   ta.replaceRange(null, start, end);
 }

}

 </source>
   
  
 
  

JTextArea: setCaretColor(Color c)

   <source lang="java">

import java.awt.Color; import javax.swing.JTextArea; import javax.swing.text.JTextComponent; public class Main {

 public static void main(String[] argv) throws Exception {
   JTextComponent c = new JTextArea();
   c.getCaretPosition();
   if (c.getCaretPosition() < c.getDocument().getLength()) {
     char ch = c.getText(c.getCaretPosition(), 1).charAt(0);
   }
   // Set the caret color
   c.setCaretColor(Color.red);
 }

}

 </source>
   
  
 
  

JTextArea: setLineWrap(boolean wrap)

   <source lang="java">

import java.awt.BorderLayout; import java.awt.Dimension; import javax.swing.JFrame; import javax.swing.JSplitPane; import javax.swing.JTextArea; public class MainClass extends JFrame {

 static String sometext = "Text Text Text Text Text Text Text Text Text Text Text Text ";
 public MainClass() {
   super("Simple SplitPane Frame");
   setSize(450, 200);
   setDefaultCloseOperation(EXIT_ON_CLOSE);
   JTextArea jt1 = new JTextArea(sometext);
   JTextArea jt2 = new JTextArea(sometext);
   jt1.setLineWrap(true);
   jt2.setLineWrap(true);
   jt1.setMinimumSize(new Dimension(150, 150));
   jt2.setMinimumSize(new Dimension(150, 150));
   jt1.setPreferredSize(new Dimension(250, 200));
   JSplitPane sp = new JSplitPane(JSplitPane.HORIZONTAL_SPLIT, jt1, jt2);
   getContentPane().add(sp, BorderLayout.CENTER);
 }
 public static void main(String args[]) {
   MainClass ssb = new MainClass();
   ssb.setVisible(true);
 }

}

 </source>
   
  
 
  

JTextArea: setTabSize(int size)

   <source lang="java">

import java.awt.Font; import javax.swing.JTextArea; public class Main {

 public static void main(String[] argv) {
   JTextArea textarea = new JTextArea();
   // Get the default tab size
   int tabSize = textarea.getTabSize(); // 8
   // Change the tab size
   tabSize = 4;
   textarea.setTabSize(tabSize);
   Font font = textarea.getFont();
   System.out.println(font);
 }

}

 </source>
   
  
 
  

JTextArea: setWrapStyleWord(boolean word)

   <source lang="java">

/*line 0 starts at 0, ends at 5 line 1 starts at 5, ends at 12 line 2 starts at 12, ends at 16 offset 0 is on line 0 offset 1 is on line 0 offset 2 is on line 0 offset 3 is on line 0 offset 4 is on line 0 offset 5 is on line 1 offset 6 is on line 1 offset 7 is on line 1 offset 8 is on line 1 offset 9 is on line 1 offset 10 is on line 1 offset 11 is on line 1 offset 12 is on line 2 offset 13 is on line 2 offset 14 is on line 2 offset 15 is on line 2 offset 16 is on line 2 offset 17 is on javax.swing.text.BadLocationException: Can"t translate offset to line

• /

import javax.swing.JFrame; import javax.swing.JScrollPane; import javax.swing.JTextArea; import javax.swing.text.BadLocationException; public class MainClass {

 public static void main(String[] args) {
   JTextArea ta = new JTextArea();
   ta.setLineWrap(true);
   ta.setWrapStyleWord(true);
   JScrollPane scroll = new JScrollPane(ta);
   ta.append("www.\n");
   ta.append("jexp\n");
   ta.append(".ru");
   try {
     for (int n = 0; n < ta.getLineCount(); n += 1)
       System.out.println("line " + n + " starts at " + ta.getLineStartOffset(n) + ", ends at "
           + ta.getLineEndOffset(n));
     System.out.println();
     int n = 0;
     while (true) {
       System.out.print("offset " + n + " is on ");
       System.out.println("line " + ta.getLineOfOffset(n));
       n += 1;
     }
   } catch (BadLocationException ex) {
     System.out.println(ex);
   }
   JFrame f = new JFrame();
   f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
   f.getContentPane().add(scroll, java.awt.BorderLayout.CENTER);
   f.setSize(150, 150);
   f.setVisible(true);
 }

}

 </source>
   
  
 
  

JTextArea: write(Writer out)

   <source lang="java">

import java.awt.BorderLayout; import java.io.FileWriter; import java.io.IOException; import javax.swing.JFrame; import javax.swing.JTextField; public class MainClass {

 public static void main(String args[]) throws Exception {
   JFrame frame = new JFrame();
   frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
   JTextField nameTextField = new JTextField();
   frame.add(nameTextField, BorderLayout.NORTH);
   
   FileWriter writer = null;
   try {
     writer = new FileWriter("filename.txt");
     nameTextField.write(writer);
   } catch (IOException exception) {
     System.err.println("Save oops");
     exception.printStackTrace();
   } finally {
     if (writer != null) {
       try {
         writer.close();
       } catch (IOException exception) {
         System.err.println("Error closing writer");
         exception.printStackTrace();
       }
     }
   }
   
   frame.setSize(250, 100);
   frame.setVisible(true);
 }

}

 </source>
   
  
 
  

JTextField: setHorizontalAlignment(int pos)

   <source lang="java">

import java.awt.GridLayout; import javax.swing.JFrame; import javax.swing.JTextField; public class MainClass {

 public static void main(final String args[]) {
   JFrame frame = new JFrame("Alignment Example");
   frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
   frame.setLayout(new GridLayout(0, 1));
   JTextField textField = new JTextField("Left");
   textField.setHorizontalAlignment(JTextField.LEFT);
   frame.add(textField);
   textField = new JTextField("Center");
   textField.setHorizontalAlignment(JTextField.CENTER);
   frame.add(textField);
   textField = new JTextField("Right");
   textField.setHorizontalAlignment(JTextField.RIGHT);
   frame.add(textField);
   textField = new JTextField("Leading");
   textField.setHorizontalAlignment(JTextField.LEADING);
   frame.add(textField);
   textField = new JTextField("Trailing");
   textField.setHorizontalAlignment(JTextField.TRAILING);
   frame.add(textField);
   frame.pack();
   frame.setSize(250, (int) frame.getSize().getHeight());
   frame.setVisible(true);
 }

}

 </source>
   
  
 
  

new JTextArea(Document document)

   <source lang="java">

import java.awt.Container; import javax.swing.BoxLayout; import javax.swing.JFrame; import javax.swing.JScrollPane; import javax.swing.JTextArea; import javax.swing.text.Document; public class MainClass {

 public static void main(String args[]) {
   JFrame frame = new JFrame("Sharing Sample");
   frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
   Container content = frame.getContentPane();
   JTextArea textarea1 = new JTextArea();
   Document document = textarea1.getDocument();
   JTextArea textarea2 = new JTextArea(document);
   JTextArea textarea3 = new JTextArea(document);
   content.setLayout(new BoxLayout(content, BoxLayout.Y_AXIS));
   content.add(new JScrollPane(textarea1));
   content.add(new JScrollPane(textarea2));
   content.add(new JScrollPane(textarea3));
   frame.setSize(300, 400);
   frame.setVisible(true);
 }

}

 </source>
   
  
 
  

new JTextArea(String text)

   <source lang="java">

import javax.swing.JTextArea; public class Main {

 public static void main(String[] argv) {
   // Create a text area with some initial text
   JTextArea textarea = new JTextArea("Initial Text");
   int rows = 20;
   int cols = 30;
   textarea = new JTextArea("Initial Text", rows, cols);
 }

}

 </source>
   
  
 
  

new JTextArea(String text, int rows, int columns)

   <source lang="java">

import javax.swing.JTextArea; public class Main {

 public static void main(String[] argv) {
   // Create a text area with some initial text
   JTextArea textarea = new JTextArea("Initial Text");
   int rows = 20;
   int cols = 30;
   textarea = new JTextArea("Initial Text", rows, cols);
 }

}

 </source>