Opening a new window when double clicking on a JTable row

Add a MouseListener to your JTable.

Main.java:

import java.awt.event.*;
import javax.swing.*;
import java.awt.*;
 
public class Main extends JFrame 
{
   public Main() {
      super("Table example, Wines from Bordeaux");
 
      final Object[][] tabledata = {
            { "Chateau Meyney, St. Estephe", 	   new Integer(1994), "$18.75"},
            { "Chateau Montrose, St. Estephe", 	   new Integer(1975), "$54.25" },
            { "Chateau Gloria, St. Julien", 	   new Integer(1993), "$22.99" },
            { "Chateau Beychevelle, St. Julien",   new Integer(1970), "$61.63" },
            { "Chateau La Tour de Mons, Margeaux", new Integer(1975), "$57.03" },
            { "Chateau Brane-Cantenac, Margeaux",  new Integer(1978), "$49.92" },
      };
 
      String columnheaders[] = { "Wine", "Vintage", "Price" };
 
      JTable table = new JTable(tabledata, columnheaders) {
         public boolean editCellAt(int row, int column, java.util.EventObject e) {
            return false;
         }
      };
 
      table.setSelectionMode(ListSelectionModel.SINGLE_SELECTION);
      table.setPreferredScrollableViewportSize(new Dimension(500, 70));
      JScrollPane scrollPane = new JScrollPane(table);
      getContentPane().add(scrollPane);
 
      addWindowListener(new WindowAdapter() {
         public void windowClosing(WindowEvent we) {
            System.exit(0);
         }
      });
 
      pack();
 
      table.addMouseListener(new MouseAdapter() {
         public void mouseClicked(MouseEvent e) {
            if (e.getClickCount() == 2) {
               JTable target = (JTable) e.getSource();
               int row = target.getSelectedRow();
               StringBuffer sb = new StringBuffer();
               String lineSeparator = System.getProperty("line.separator");
               sb.append(tabledata[row][0] + lineSeparator);
               sb.append(tabledata[row][1] + lineSeparator);
               sb.append(tabledata[row][2] + lineSeparator);
               TextFrame textFrame = new TextFrame(sb.toString());
               textFrame.setVisible(true);
            }
         }
      });
   }
 
   public static void main(String []args) {
      Main main = new Main();
      main.show();
   }
}
 
class TextFrame extends JFrame
{
   public TextFrame(String content) {
      super("TextFrame");
 
      JTextArea ta = new JTextArea();
      ta.setText(content);
      getContentPane().add(ta);
      addWindowListener(new WindowAdapter() {
         public void windowClosing(WindowEvent we) {
            dispose();
         }
      });
      
      setSize(200, 100);
   }
}

Render HTML documents

JEditorPane is able to display and edit different kinds of content. By default,
text/plain, text/html and text/rtf are recognized and passed on to the
EditorKit that is designed to handle it: DefaultEditorKit, HTMLEditorKit and
RTFEditorKit
. In the following example, a URL can be given in a JTextField.
Clicking GO will invoke the setPage method on the JEditorPane that will load
the page into a default document and set the content type. Using the
mime type of the page, the pane will automatically detect the correct EditorPane to
use.
Try: http://www.yahoo.com and http://www.esus.com/richtext.rtf

import javax.swing.text.html.*;
import javax.swing.text.*;
import java.awt.event.*;
import javax.swing.*;
import java.net.*;
import java.awt.*;
import java.io.*;
 
public class Main extends JFrame
{
   public static void main(String []args) {
      Main main = new Main();
      main.show();
   }
 
   public Main() {
 
      JButton uriButton = new JButton("Go!");
      // needs to be final to allow the inner class to access it!
      final JTextField uriTextField = new JTextField();
      final JEditorPane htmlPane = new JEditorPane();
      uriTextField.setText("http://www.yahoo.com");
      htmlPane.setEditable(false);
 
      uriButton.addActionListener(new ActionListener() {
         public void actionPerformed(ActionEvent ae) {
            try {
               htmlPane.setPage(new URL(uriTextField.getText()));
            }
            catch(Exception e) {
               System.out.println(e);
            }
         }
      });
 
      getContentPane().setLayout(new BorderLayout());
      JPanel topPanel = new JPanel(new BorderLayout());
      topPanel.add(BorderLayout.CENTER, uriTextField);
      topPanel.add(BorderLayout.EAST, uriButton);
 
      getContentPane().add(BorderLayout.NORTH, topPanel);
      getContentPane().add(BorderLayout.CENTER, new JScrollPane(htmlPane));
 
      addWindowListener(new WindowAdapter() {
         public void windowClosing(WindowEvent e) {
            System.exit(0);
         }
      });
 
      setSize(400, 400);
   }
}

Allowing for multiple selections in a JTree

Use TreeSelectionModel.DISCONTIGUOUS_TREE_SELECTION!

Main.java:

import javax.swing.*;
import javax.swing.tree.*;
import javax.swing.event.*;
import java.awt.*;
import java.net.*;
import java.awt.event.*;
 
public class Main extends JFrame
{
   public Main() {
      DefaultMutableTreeNode root = createNodes();
      final JTree tree = new JTree(root);
 
      TreeSelectionModel model = new DefaultTreeSelectionModel();
      model.setSelectionMode(TreeSelectionModel.DISCONTIGUOUS_TREE_SELECTION);
      tree.setSelectionModel(model);
 
      JButton button = new JButton("Display selected values on stdout");
      button.addActionListener(new ActionListener() {
         public void actionPerformed(ActionEvent ae) {
            TreePath[] treePaths = tree.getSelectionPaths();    
            for (int i=0; i<treePaths.length; i++) {
               System.out.println(treePaths[i].getLastPathComponent());    
            }
         }
      });
 
      getContentPane().setLayout(new BorderLayout());
      getContentPane().add(BorderLayout.CENTER, new JScrollPane(tree));
      getContentPane().add(BorderLayout.SOUTH, button);
 
      addWindowListener(new WindowAdapter() {
         public void windowClosing(WindowEvent we) {
            System.exit(0);
         }
      });
   }
 
   public static DefaultMutableTreeNode createNodes() {
      DefaultMutableTreeNode root = new DefaultMutableTreeNode("Java");
      
      DefaultMutableTreeNode j2se = new DefaultMutableTreeNode("J2SE");
      DefaultMutableTreeNode j2ee = new DefaultMutableTreeNode("J2EE");
      DefaultMutableTreeNode j2me = new DefaultMutableTreeNode("J2ME");
 
      j2se.add(new DefaultMutableTreeNode("http://java.sun.com/j2se/"));
      j2ee.add(new DefaultMutableTreeNode("http://java.sun.com/j2ee/"));
      j2me.add(new DefaultMutableTreeNode("http://java.sun.com/j2me/"));
 
      root.add(j2se);
      root.add(j2ee);
      root.add(j2me);
 
      return root;
   }
 
   public static void main(String []args) {
      Main main = new Main();
      main.setSize(400, 400);
      main.setVisible(true);
   }
}

Creating an SWT Text(Area)

Main.java:

import org.eclipse.swt.SWT;
import org.eclipse.swt.layout.GridData;
import org.eclipse.swt.layout.GridLayout;
import org.eclipse.swt.widgets.Display;
import org.eclipse.swt.widgets.Shell;
import org.eclipse.swt.widgets.Text;
 
public class Main {
   public static void main(String[] args) {
      Display display = new Display();
      Shell shell = new Shell(display);
 
      // pos x, pos y, width, height
      shell.setBounds(200, 200, 300, 200);
      shell.setText("SWT Text Demonstration");
      shell.setLayout(new GridLayout());
 
      shell.setLayoutData(new GridData(GridData.FILL_HORIZONTAL));
 
      Text text = new Text(shell, SWT.BORDER | SWT.H_SCROLL | SWT.V_SCROLL | SWT.WRAP);
      text.setLayoutData(new GridData(GridData.FILL_HORIZONTAL | GridData.FILL_VERTICAL));
       
      text.setText("Did you know..." +
                   "nn" +
                   "It is impossible to lick your elbow." +
                   "nnnnnnnnnnnnnnn" +
                   "Over 75% of people who read thisn" +
                   "will try to lick their elbow.");
       
      shell.open();
 
      while (!shell.isDisposed()) {
         if (!display.readAndDispatch()) {
            display.sleep();
         }
      }
       
      display.dispose();
   }
}

Creating a JFormattedTextField that only accepts dates

Main.java and JFormattedDateTextField:

import javax.swing.text.*;
import java.awt.event.*;
import javax.swing.*;
import java.text.*;
import java.awt.*;
import java.util.*;
 
public class Main extends JFrame 
{
   public Main() throws Exception
   {
      addWindowListener(new WindowAdapter() {
         public void windowClosing(WindowEvent we) {
            System.exit(1);
         }
      });
  
 
      final JFormattedDateTextField formattedTf =
                   new JFormattedDateTextField();
      formattedTf.setValue(new Date()); 
 
      final JTextField normalTf = new JTextField(25);
      JButton button = new JButton("Get value");
      button.addActionListener(new ActionListener() {
         public void actionPerformed(ActionEvent ae) { 
            normalTf.setText(""+formattedTf.getValue());
         }
      });
 
      getContentPane().setLayout(new FlowLayout(FlowLayout.LEFT));
      getContentPane().add(formattedTf);
      getContentPane().add(button);
      getContentPane().add(normalTf);
 
      formattedTf.setPreferredSize(normalTf.getPreferredSize());
   }
  
   public static void main(String args[]) throws Exception 
   {
      Main main = new Main();
      main.setSize(300, 150);
      main.setVisible(true);
   }
}
 
class JFormattedDateTextField extends JFormattedTextField {
   Format format = new SimpleDateFormat("MM/dd/yyyy"); 
 
   public JFormattedDateTextField() {
      super();
      MaskFormatter maskFormatter = null;
      try {
         maskFormatter = new MaskFormatter("##/##/####");
      } catch (ParseException e) {
         e.printStackTrace();
      }
 
      maskFormatter.setPlaceholderCharacter('_');
      setFormatterFactory(new DefaultFormatterFactory(maskFormatter));
      this.addFocusListener(new FocusAdapter() {
         public void focusGained(FocusEvent e) {
            if (getFocusLostBehavior() == JFormattedTextField.PERSIST)
               setFocusLostBehavior(JFormattedTextField.COMMIT_OR_REVERT);
            }
  
            public void focusLost(FocusEvent e) {
               try {
                  Date date = (Date) format.parseObject(getText());
                  setValue(format.format(date));
               } catch (ParseException pe) {
                  setFocusLostBehavior(JFormattedTextField.PERSIST);
                  setText("");
                  setValue(null);
               }
            }
      });
   }
 
   public void setValue(Date date) {
      super.setValue(toString(date));
   }
 
   private Date toDate(String sDate) {
      Date date = null;
      if (sDate == null) return null;
      try {
         date = (Date) format.parseObject(sDate);
      }
      catch (ParseException pe) {
         // ignore
      }
 
      return date;
   } 
 
   private String toString(Date date) {
      try {
         return format.format(date);
      } catch (Exception e) {
         return "";
      }
   }
}

Maximizing an AWT Frame

From 1.3 onwards, use setExtendedState(Frame.MAXIMIZED_BOTH)

Main.java:

import java.awt.event.*;
import java.awt.*;
 
public class Main extends Frame implements ActionListener
{
   public Main()
   {
      addWindowListener(new WindowAdapter() {
         public void windowClosing(WindowEvent we) {
            System.exit(1);
         }
      });
 
      Button maxButton = new Button("Maximize this Frame");
      setLayout(new FlowLayout(FlowLayout.LEFT));
      add(maxButton);
      maxButton.addActionListener(this);
   }
 
   public void actionPerformed(ActionEvent ae) {     
      setExtendedState(Frame.MAXIMIZED_BOTH);
   }
 
   public static void main(String args[])
   {
      Main main = new Main();
      main.setSize(300, 150);
      main.setVisible(true);
   }
}

Drawing a filled round rectangle in Swing

Main.java:

import java.awt.event.*;
import javax.swing.*;
import java.awt.*;
 
public class Main extends JFrame {
   public Main() {
      addWindowListener(new WindowAdapter() {
         public void windowClosing(WindowEvent we) {
            System.exit(1);
         }
      });
   }
 
   public void paint(Graphics g) {
      Graphics2D g2d = (Graphics2D) g;
  
      g2d.setColor(Color.green);
      g2d.fillRoundRect(10, 50, 150, 70, 50, 30);
   }
 
   public static void main(String []args) {
      Main main = new Main();
      main.setSize(170, 150);
      main.setVisible(true);
   }
}

Drawing a texture-filled text in Swing

Result:

Texture:

Main.java:

import java.awt.image.*;
import java.awt.event.*;
import java.awt.geom.*;
import javax.swing.*;
import java.awt.*;
 
public class Main extends JFrame {
   private BufferedImage image; 
 
   public Main() {
      addWindowListener(new WindowAdapter() {
         public void windowClosing(WindowEvent we) {
            System.exit(1);
         }
      });
 
      image = toBufferedImage(new javax.swing.ImageIcon("djkrush.jpg").getImage());
   }
 
   public void paint(Graphics g) {
      Graphics2D g2d = (Graphics2D) g;
       
      g2d.setRenderingHint(RenderingHints.KEY_ANTIALIASING,
                           RenderingHints.VALUE_ANTIALIAS_ON);
 
      Font font = new Font("Serif", Font.PLAIN, 140);
      g2d.setFont(font);
 
      Rectangle2D tr = new Rectangle2D.Double(0, 0, image.getWidth(), image.getHeight());
      TexturePaint tp = new TexturePaint(image, tr);
      g2d.setPaint(tp);
      g2d.drawString("Alicia", 30, 150);
   }
 
   public BufferedImage toBufferedImage(Image image) {
      BufferedImage bi = new BufferedImage(image.getWidth(null), image.getHeight(null), 
                                           BufferedImage.TYPE_INT_RGB); 
 
      // copy the original image
      Graphics g = bi.createGraphics();
    
      g.drawImage(image, 0, 0, null);
      g.dispose();
 
      return bi;
   }
 
   public static void main(String []args) {
      Main main = new Main();
      main.setSize(410, 180);
      main.setVisible(true);
   }
}

Drawing anti-aliased text in Swing

Main.java:

import java.awt.event.*;
import javax.swing.*;
import java.awt.*;
 
public class Main extends JFrame {
   private boolean antiAliasing = false;
 
   public Main() {
      addWindowListener(new WindowAdapter() {
         public void windowClosing(WindowEvent we) {
            System.exit(1);
         }
      });
 
      final JCheckBox cb = new JCheckBox("Anti-aliased");
      cb.addItemListener(new ItemListener() {
         public void itemStateChanged(ItemEvent e) {
            antiAliasing = cb.isSelected();
            repaint();
         }
      });
 
      getContentPane().setLayout(new BorderLayout());
      getContentPane().add(BorderLayout.NORTH, cb);
   }
 
   public void paint(Graphics g) {
      super.paint(g);
 
      Graphics2D g2d = (Graphics2D) g;
       
      if (antiAliasing) {
         g2d.setRenderingHint(RenderingHints.KEY_ANTIALIASING,
                              RenderingHints.VALUE_ANTIALIAS_ON);
      }
 
      Font font = new Font("Serif", Font.PLAIN, 140);
      g2d.setFont(font);
 
      g2d.drawString("W", 60, 150);
   }
 
   public static void main(String []args) {
      Main main = new Main();
      main.setSize(300, 300);
      main.setVisible(true);
   }
}

Zero out all pixels of a RGB band in Swing

Use the class LookupOp and pass it an array of arrays, each representing the change in band. In this example, the G(reen) and B(lue) band don’t change while the R(ed) value is made zero for all intensities.

Main.java:

import java.awt.image.*;
import java.awt.event.*;
import javax.swing.*;
import java.awt.*;
 
public class Main extends JFrame {
   private boolean firstTime = true;
   private BufferedImage sourceBi;
   private BufferedImage destBi;
 
   public Main() {
      addWindowListener(new WindowAdapter() {
         public void windowClosing(WindowEvent we) {
            System.exit(1);
         }
      }); 
   } 
 
   public void paint(Graphics graphics) {
      Graphics2D g2d = (Graphics2D) graphics;
  
      if (firstTime) {
         Image img = new javax.swing.ImageIcon("djkrush.jpg").getImage(); 
         sourceBi = toBufferedImage(img);
         destBi = new BufferedImage(sourceBi.getWidth(), sourceBi.getHeight(), 
                                    BufferedImage.TYPE_INT_RGB);
         setSize(sourceBi.getWidth(), sourceBi.getHeight()*2);
 
         byte[][] intensity = new byte[3][256];
         for(int i=0; i<256; i++) {
            intensity[0][i] = 0;
            intensity[1][i] = (byte) i;
            intensity[2][i] = (byte) i;
         }
  
         ByteLookupTable blt = new ByteLookupTable(0, intensity);
         LookupOp op = new LookupOp(blt, null);
         destBi = op.filter(sourceBi, null);
 
         firstTime = false;
      }
 
      g2d.drawImage(sourceBi, 0, 0, this);
      g2d.drawImage(destBi, 0, sourceBi.getHeight(), this);
   }
 
   public static BufferedImage toBufferedImage(Image image) {
      BufferedImage bi = new BufferedImage(image.getWidth(null), image.getHeight(null), 
                                           BufferedImage.TYPE_INT_RGB); 
 
      // copy the original image
      Graphics g = bi.createGraphics();
    
      g.drawImage(image, 0, 0, null);
      g.dispose();
 
      return bi;
   }
 
   public static void main(String []args) {
      Main main = new Main();
      main.setVisible(true);
      main.setSize(300, 150);
   }
}

Image used:

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