Eclipse Bug: Unhandled event loop exception No more handles

I've built a GUI using Swing and the MigLayout.

I am using Eclipse 4.2.2 (64-bit) on Windows 7 Ultimate. Every time I click back into the window to edit my code, a popup comes up, then I'm prompted to restart Eclipse, and the Event log says the following:

 org.eclipse.swt.SWTError: No more handles
    at org.eclipse.swt.SWT.error(SWT.java:4387)
    at org.eclipse.swt.SWT.error(SWT.java:4276)
    at org.eclipse.swt.SWT.error(SWT.java:4247)
    at org.eclipse.swt.widgets.Widget.error(Widget.java:468)
    at org.eclipse.swt.widgets.Control.createHandle(Control.java:704)
    at org.eclipse.swt.widgets.Label.createHandle(Label.java:199)
    at org.eclipse.swt.widgets.Control.createWidget(Control.java:744)
    at org.eclipse.swt.widgets.Control.<init>(Control.java:112)
    at org.eclipse.swt.widgets.Label.<init>(Label.java:101)
    ...

I'm attaching screenshots of the error messages. Has anyone else encountered this bug with Eclipse? Do you know of a work-around or a fix?

There is a workaround: Change the Java editor to WindowBuilder.

Eclipse → Windows → Preferences → File Associations →, choose WindowBuilder Editor as Java default editor.