[platform-debug-dev] IDebugContextProvider API and external usage of the

[Stefan Bylund <steby@xxxxxxx>]

Hi,

A collegue of mine, Elin Karasalo, recently asked why a code snippet 
using the Memory View doesn't work with Eclipse 3.2 but with Eclipse 
3.1.2. Samantha Chan suggested that we should review the getAdapter() 
methods in our memory block and memory block retrieval implementations. 
I looked at the CDT implementations of these classes to get an 
understanding of what adapters you are expected to support and I think 
we cover these now. By the way, why is there no info in the Javadoc for 
org.eclipse.debug about what adapters you are supposed to handle when, 
for example, using the Memory View?

Samantha, you also said that the memory block and memory block retrieval 
implementations should extend PlatformObject. Isn't it enough to just 
implement IAdaptable and delegate to 
Platform.getAdapterManager().getAdapter(), which would be equivalent to 
delegating to PlatformObject? Or does the Memory View explicitly check 
for instaceof PlatformObject?

Since making our getAdapter() methods handle the expected adapters 
didn't solve our problem (the Memory View is still empty), I debugged 
what really happened and realised that the Memory View in Eclipse 3.2 
requires an active selection from the Debug View to work at all. This 
wasn't the case in Eclipse 3.1. However, I was glad that see that the 
Memory View isn't coupled directly to the Debug View per se, but 
actually to the current IDebugContextProvider. So I implemented my own 
IDebugContextProvider and hooked it in by calling:
DebugContextManager.getDefault().addDebugContextProvider(myDebugContextProvider)

Voila, now I see my memory blocks appearing in the Memory View! However, 
the image and text labels are not displayed for the memory blocks, 
instead a small empty selection rectangle is displayed, and the 
rendering is without content... I will try to find out what is missing 
by debugging the Memory View.

My main question is regarding IDebugContextProvider. I think that it is 
extremely useful to be able to add your own debug context provider in 
order to use the Memory View and other context-sensitive debug related 
views without having a running source code debug session. However, 
IDebugContextProvider and its mate IDebugContextListener are located in 
the org.eclipse.debug.internal.ui.contexts.provisional package and the 
DebugContextManager in the org.eclipse.debug.internal.ui.contexts 
package. Is it the intention to make these three classes/interfaces 
public in Eclipse 3.3 so that the IDebugContextProvider concept can be 
fully used? Can we safely start using it with Eclipse 3.2?

Kind regards,
Stefan