CDT之DSF-GDB分析

GdbAdapterFactory

是Launch对象的适配器工厂，他主要使用GdbSessionAdapters来创建所有和Launch有关的适配器

public class GdbAdapterFactory {
	public <T> T getAdapter(Object adaptableObject, Class<T> adapterType) {
        GdbSessionAdapters adapterSet = createGdbSessionAdapters(launch, session);
        fgLaunchAdapterSets.put(launch, adapterSet);
        return adapterSet.getLaunchAdapter(adapterType);
	}
    protected GdbSessionAdapters createGdbSessionAdapters(ILaunch launch, DsfSession session) {
		return new GdbSessionAdapters(launch, session, getAdapterList());
	}
}
//用来创建和保存适配器实例
public class GdbSessionAdapters {
	private final Map<Class<?>, Object> fLaunchAdapters = new HashMap<>(); // 保存plugin.xml中定义的与Launch关联的几个适配器
	private final Class<?>[] fLaunchAdapterTypes;
	public GdbSessionAdapters(ILaunch launch, DsfSession session, Class<?>[] launchAdapterTypes) {
		fLaunch = launch;
        fSession = session;
		fLaunchAdapterTypes = launchAdapterTypes;
		createAdapters(); //创建所有的适配器
	}
    protected void createAdapters() {
		for (Class<?> adapterType : getModelAdapters()) {//创建所有的适配器并且关联到session中
			Object adapter = createModelAdapter(adapterType, getLaunch(), getSession());
			getSession().registerModelAdapter(adapterType, adapter);

		}
		for (Class<?> adapterType : fLaunchAdapterTypes) {//创建与Launch关联的适配器
			Object adapter = createLaunchAdapter(adapterType, getLaunch(), getSession());
			fLaunchAdapters.put(adapterType, adapter);
		}
	}
    protected <T> T createModelAdapter(Class<T> adapterType, ILaunch launch, DsfSession session) {
		if (IViewerInputProvider.class.equals(adapterType)) {
            //注意此处，GdbViewModelAdapter实现了跟UI相关的所有接口，和UI相关的适配器都会返回这个实例
			return (T) new GdbViewModelAdapter(session, getSteppingController());
		}
        // ... ... ...
		if (IDebugModelProvider.class.equals(adapterType)) {
			return (T) new IDebugModelProvider() {
				@Override
				public String[] getModelIdentifiers() {
                    //在这里添加自己的model id
					return new String[] { GdbLaunchDelegate.GDB_DEBUG_MODEL_ID,
							ICBreakpoint.C_BREAKPOINTS_DEBUG_MODEL_ID, "org.eclipse.cdt.gdb" //$NON-NLS-1$
					};
				}
			};
		}
		return null;
	}
    protected <T> T createLaunchAdapter(Class<T> adapterType, ILaunch launch, DsfSession session) {
		if (adapterType.equals(IElementContentProvider.class) || adapterType.equals(IModelProxyFactory.class)
				|| adapterType.equals(IColumnPresentationFactory.class)) {
			return (T) getViewModelAdapter(); //和UI相关的适配器就是IViewerInputProvider的适配器，他们是同一个
		}
		if (adapterType.equals(ISuspendTrigger.class)) {
			return (T) new GdbSuspendTrigger(session, launch);
		}
		return null;
	}
}
           

GdbViewModelAdapter

IVMAdapter

他的主要作用就是管理IVMProvider，通过IPresentationContext的id把逻辑处理转给对应的IVMProvider

public interface IVMAdapter
		extends IElementContentProvider, 
				IModelProxyFactory, 
				IColumnPresentationFactory, 
				IViewerInputProvider {
	/**
	 * Returns the View Model Provider that is registered for the given presentation
	 * context.  Returns <code>null</code> if there is none.
	 */
    // 根据presentationContext中的view id，返回对应的IVMProvider，如果没有的话则创建
	public IVMProvider getVMProvider(IPresentationContext presentationContext);

	/**
	 * Retrieves the currently active VM providers in this adapter.
	 * @return array of VM providers
	 */
	public IVMProvider[] getActiveProviders();

}

public class GdbViewModelAdapter extends AbstractDebugVMAdapter {
    //根据presentationContext中的view id，创建IVMProvider
	protected IVMProvider createViewModelProvider(IPresentationContext context) {
		if (IDebugUIConstants.ID_DEBUG_VIEW.equals(context.getId())) {
			return new LaunchVMProvider(this, context, getSession());
		}  
        // ... ... ...
        else if (IDebugUIConstants.ID_REGISTER_VIEW.equals(context.getId())) {
			return new RegisterVMProvider(this, context, getSession());
		} 
		return null;
	}
}

           

IVMProvider

与IVMAdapter的继承结构相似，IVMAdapter虽然继承了与视图相关的4个接口，但他不会直接处理或提供与视图相关的功能数据，而是再实例化一个或多个IVMProvider对象（目测一个view对应一个IVMProvider），IVMAdapter会调用IVMProvider对应的方法来提供视图相关的功能数据。例如:

IVMAdapter:createModelProxy()->IVMProvider:createModelProxy()

abstract public class AbstractVMAdapter implements IVMAdapter {
    // ...
	@Override
	public IModelProxy createModelProxy(Object element, IPresentationContext context) {
		IVMProvider provider = getVMProvider(context); //拿到对应view的provider
		if (provider != null) {
			return provider.createModelProxy(element, context);//看此处
		}
		return null;
	}
    // ...
}
           

DefaultVMContentProviderStrategy, DefaultVMModelProxyStrategy

继承了IElementContentProvider接口，AbstractVMProvider也不会直接提供对应的功能数据，而是通过createContentStrategy()方法创建一个IElementContentProvider对象，然后在对应的update()方法中调用后者中的update()方法。大致如下：

IVMAdapter.update()->IVMProvider.update()->DefaultVMModelProxyStrategy.update()