Strange JTable issue in Sun's Java code

From	Novice <novice@example..com>
Newsgroups	comp.lang.java.gui
Subject	Strange JTable issue in Sun's Java code
Date	2012-01-16 18:34 +0000
Organization	Your Company
Message-ID	<Xns9FDC8ADEB9988jpnasty@94.75.214.39> (permalink)

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I'm getting an exception I don't understand when I attempt to delete all 
the data in a small Jtable (46 rows, 3 columns). 

Here's the stacktrace; the "rowCount = 45" is a diagnostic I'm writing:
========================================================================
rowCount = 45
Exception in thread "AWT-EventQueue-0" 
java.lang.ArrayIndexOutOfBoundsException: 0
	at javax.swing.SizeSequence.removeEntries(SizeSequence.java:383)
	at javax.swing.JTable.tableRowsDeleted(JTable.java:4500)
	at javax.swing.JTable.tableChanged(JTable.java:4399)
	at javax.swing.table.AbstractTableModel.fireTableChanged
(AbstractTableModel.java:280)
	at javax.swing.table.AbstractTableModel.fireTableRowsDeleted
(AbstractTableModel.java:245)
	at hang.PhraseListTableModel.deleteAllRows
(PhraseListTableModel.java:634)
	at hang.PhraseListEditor.actionPerformed(PhraseListEditor.java:625)
	at javax.swing.AbstractButton.fireActionPerformed
(AbstractButton.java:1995)
	at javax.swing.AbstractButton$Handler.actionPerformed
(AbstractButton.java:2318)
	at javax.swing.DefaultButtonModel.fireActionPerformed
(DefaultButtonModel.java:387)
	at javax.swing.DefaultButtonModel.setPressed
(DefaultButtonModel.java:242)
	at javax.swing.AbstractButton.doClick(AbstractButton.java:357)
	at javax.swing.plaf.basic.BasicMenuItemUI.doClick
(BasicMenuItemUI.java:1223)
	at javax.swing.plaf.basic.BasicMenuItemUI$Handler.mouseReleased
(BasicMenuItemUI.java:1264)
	at java.awt.Component.processMouseEvent(Component.java:6263)
	at javax.swing.JComponent.processMouseEvent(JComponent.java:3267)
	at java.awt.Component.processEvent(Component.java:6028)
	at java.awt.Container.processEvent(Container.java:2041)
	at java.awt.Component.dispatchEventImpl(Component.java:4630)
	at java.awt.Container.dispatchEventImpl(Container.java:2099)
	at java.awt.Component.dispatchEvent(Component.java:4460)
	at java.awt.LightweightDispatcher.retargetMouseEvent
(Container.java:4574)
	at java.awt.LightweightDispatcher.processMouseEvent
(Container.java:4238)
	at java.awt.LightweightDispatcher.dispatchEvent(Container.java:4168)
	at java.awt.Container.dispatchEventImpl(Container.java:2085)
	at java.awt.Window.dispatchEventImpl(Window.java:2478)
	at java.awt.Component.dispatchEvent(Component.java:4460)
	at java.awt.EventQueue.dispatchEvent(EventQueue.java:599)
	at java.awt.EventDispatchThread.pumpOneEventForFilters
(EventDispatchThread.java:269)
	at java.awt.EventDispatchThread.pumpEventsForFilter
(EventDispatchThread.java:184)
	at java.awt.EventDispatchThread.pumpEventsForHierarchy
(EventDispatchThread.java:174)
	at java.awt.EventDispatchThread.pumpEvents
(EventDispatchThread.java:169)
	at java.awt.EventDispatchThread.pumpEvents
(EventDispatchThread.java:161)
	at java.awt.EventDispatchThread.run(EventDispatchThread.java:122)
========================================================================

The crash is happening in the Java code but here's my deleteAllRows() so 
that you can see nothing very exotic is happening:

========================================================================
	public int deleteAllRows() {

		String METHOD_NAME = "deleteAllRows()"; //$NON-NLS-1$
		if (DEBUG) this.logger.entering(this.CLASS_NAME, METHOD_NAME);
		
		int rowCount = getRowCount();
		//FIXME: remove the next line
		System.err.println("rowCount = " + rowCount); //temporary 

		this.phraseList.removeAllElements();
		fireTableRowsDeleted(1, rowCount);

		return rowCount;
	}
========================================================================

When I debug the code and follow it into the Java code, some odd things 
are happening. First, the actual fireTableRowsDeleted() method shows a 
valid value for the "this" parameter but displays the following for each 
of the other parameters when I inspect them via the Eclipse debugger: 
"firstRow [or whatever] cannot be resolved to a variable". I don't recall 
ever seeing that before in debugging a program. Then, when I proceed 
beyond that to the removeEntries(int, int) method, things continue to be 
strange. When I get to line 383 of that method, I get the same "cannot be 
resolved to a variable" notation on EVERY variable in that line, even 
variable i, which has just been explicitly set to 0. 

Here's the complete code for this method:

========================================================================
    /**
     * Removes a contiguous group of entries
     * from this <code>SizeSequence</code>.
     * Note that the values of <code>start</code> and
     * <code>length</code> must satisfy the following
     * conditions:  <code>(0 <= start < getSizes().length)
     * AND (length >= 0)</code>.  If these conditions are
     * not met, the behavior is unspecified and an exception
     * may be thrown.
     * 
     * @param start   the index of the first entry to be removed
     * @param length  the number of entries to be removed
     */
   public void removeEntries(int start, int length) { 
        int sizes[] = getSizes(); 
        int end = start + length; 
        int n = a.length - length; 
        a = new int[n]; 
        for (int i = 0; i < start; i++) { 
            a[i] = sizes[i] ;
        }
        for (int i = start; i < n; i++) { 
            a[i] = sizes[i+length] ;
        }
        setSizes(a); 
    } 
========================================================================

I've never encountered a situation like this before. It feels like the 
problem is in the Java code - or Eclipse - and I'm not sure what to do 
about that. Is this nature's way of telling me that I need a newer Java 
JDK? I'm using Java 1.6.18. If not, what should I be doing?

-- 
Novice

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Thread

Strange JTable issue in Sun's Java code Novice <novice@example..com> - 2012-01-16 18:34 +0000
  Re: Strange JTable issue in Sun's Java code Jeff Higgins <jeff@invalid.invalid> - 2012-01-16 14:48 -0500
    Re: Strange JTable issue in Sun's Java code Jeff Higgins <jeff@invalid.invalid> - 2012-01-16 14:55 -0500
    Re: Strange JTable issue in Sun's Java code Jeff Higgins <jeff@invalid.invalid> - 2012-01-16 15:19 -0500
      Re: Strange JTable issue in Sun's Java code Jeff Higgins <jeff@invalid.invalid> - 2012-01-16 15:31 -0500
        Re: Strange JTable issue in Sun's Java code Jeff Higgins <jeff@invalid.invalid> - 2012-01-16 17:57 -0500
    Re: Strange JTable issue in Sun's Java code Novice <novice@example..com> - 2012-01-17 01:48 +0000
      Re: Strange JTable issue in Sun's Java code Jeff Higgins <jeff@invalid.invalid> - 2012-01-17 03:22 -0500
        Re: Strange JTable issue in Sun's Java code Jeff Higgins <jeff@invalid.invalid> - 2012-01-17 03:29 -0500
        Re: Strange JTable issue in Sun's Java code Jeff Higgins <jeff@invalid.invalid> - 2012-01-17 03:49 -0500
        Re: Strange JTable issue in Sun's Java code Jeff Higgins <jeff@invalid.invalid> - 2012-01-17 03:55 -0500
        Re: Strange JTable issue in Sun's Java code Novice <novice@example..com> - 2012-01-17 22:21 +0000
          Re: Strange JTable issue in Sun's Java code Jeff Higgins <jeff@invalid.invalid> - 2012-01-17 18:18 -0500
            Re: Strange JTable issue in Sun's Java code Jeff Higgins <jeff@invalid.invalid> - 2012-01-17 20:56 -0500
              Re: Strange JTable issue in Sun's Java code Novice <novice@example..com> - 2012-01-18 05:24 +0000
                Re: Strange JTable issue in Sun's Java code Novice <novice@example..com> - 2012-01-18 17:40 +0000
            Re: Strange JTable issue in Sun's Java code Novice <novice@example..com> - 2012-01-18 05:37 +0000
  Re: Strange JTable issue in Sun's Java code Christian Kaufhold <chka@ucuri.chka.de> - 2012-01-19 21:00 +0100

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