ErrorDialog.java

package org.freehep.swing;

import java.awt.BorderLayout;
import java.awt.Component;
import java.awt.Dimension;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

import javax.swing.JButton;
import javax.swing.JComponent;
import javax.swing.JDialog;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTabbedPane;
import javax.swing.JTextArea;
import javax.swing.SwingUtilities;
import javax.swing.WindowConstants;

/**
 * A utility for displaying errors in dialogs.
 * @author Tony Johnson
 */
public class ErrorDialog
{
   private ErrorDialog()
   {
   }
   /**
    * Creates a dialog which will display a message to the user.
    * If a Throwable is provided the user can click the "Details" button to
    * get a full stack trace, including any nested errors ("caused by").
    * @param source The parent component to be used for the dialog (may be null)
    * @param message The message to be displayed in the dialog
    * @param detail The exception that caused the error (may be null)
    */
   public static void showErrorDialog(Component source, Object message, final Throwable detail)
   {
      final JButton details = new JButton("Details...");
      details.setEnabled(detail != null);
      details.addActionListener(new ActionListener()
      {
         public void actionPerformed(ActionEvent e)
         {
            JDialog owner = (JDialog) SwingUtilities.getAncestorOfClass(JDialog.class,details);
            ErrorDetailsDialog dlg = new ErrorDetailsDialog(owner,detail);
            dlg.setDefaultCloseOperation(WindowConstants.DISPOSE_ON_CLOSE);
            dlg.pack();
            dlg.setLocationRelativeTo(owner);
            dlg.setVisible(true);
         }
      });
      if (source != null) source.getToolkit().beep();
      Object[] options = { "OK" , details };
      JOptionPane.showOptionDialog(source,message,"Error...",JOptionPane.DEFAULT_OPTION,JOptionPane.ERROR_MESSAGE,null,options,options[0]);
   }
   public static class ErrorDetailsDialog extends JDialog
   {
      public ErrorDetailsDialog(JDialog owner, Throwable detail)
      {
         super(owner);
         JComponent messageComponent = null;
         JTabbedPane tabs = null;
         Throwable ex = detail;
         for (; ex != null;)
         {
            JTextArea ta = new JTextArea();
            ta.append(ex+"\n");
            StackTraceElement[] trace = ex.getStackTrace();
            for (int i=0; i<trace.length; i++)
            {
               ta.append("    at "+trace[i]+"\n");
            }
            JScrollPane scroll = new JScrollPane(ta);
            ta.setCaretPosition(0);
            ta.setEditable(false);
            scroll.setPreferredSize(new Dimension(400,300));
            ex = ex.getCause();
            if (ex != null)
            {
               if (messageComponent == null)
               {
                  messageComponent = tabs = new JTabbedPane();
                  tabs.addTab("Exception",scroll);
               }
               else
               {
                  tabs.addTab("Caused by",scroll);
               }
            }
            else
            {
               if (messageComponent == null) messageComponent = scroll;
               else tabs.addTab("Caused by",scroll);
               break;
            }
         }
         getContentPane().add(messageComponent);
         JButton close = new JButton("Close")
         {
            public void fireActionPerformed(ActionEvent event)
            {
               dispose();
            }
         };
         JPanel panel = new JPanel();
         panel.add(close);
         getContentPane().add(panel,BorderLayout.SOUTH);
      } 
   }
}