SWT No More Handles

If I understand you correctly, you are probably getting the following exception:

org.eclipse.swt.SWTError: No more handles

You may be creating resources (such as Font, Image or GC objects) that you aren’t correctly disposing. You might want to take a moment to read through the SWT guide on Managing Operating System Resources.

To determine if this is indeed the case, I can recommend this useful article: Diagnosing Handle Leaks in SWT/RCP Windows Applications, which explains what resources are and suggests using Process Explorer or DPus to locate leaks.

A colleague also highly recommends Sleak, a SWT-focused application that can actually inform you which resources are remaining in residual memory.

For a very technical understanding of what handles SWT is making, this Sybase article describes that there are three kinds: User Object, GDI Object or Kernel Object handles, each of which has its own maximum.

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