import org.eclipse.help.HelpSystem; //导入依赖的package包/类
public static String getHelpUrl(String contextId) {
    if (contextId != null) {
        if (contextId.lastIndexOf(Constants.DOT) == -1) {
            contextId = Constants.DOCUMENTATION_PLUGIN_PREFIX + Constants.DOT + contextId;
        }

        IContext c = HelpSystem.getContext(contextId);
        if (c != null) {
            IHelpResource[] topics = c.getRelatedTopics();

            if (!Utils.isEmpty(topics)) {
                return topics[0].getHref();
            }
        }
    }

    return null;
}
 

import org.eclipse.help.HelpSystem; //导入依赖的package包/类
public IContext getContext(Object target) {
	IContext context= HelpSystem.getContext(fId);
	if (fSelected != null && fSelected.length > 0) {
		try {
			context= new JavadocHelpContext(context, fSelected);
		} catch (JavaModelException e) {
			// since we are updating the UI with async exec it
			// can happen that the element doesn't exist anymore
			// but we are still showing it in the user interface
			if (!e.isDoesNotExist())
				JavaPlugin.log(e);
		}
	}
	return context;
}
 

import org.eclipse.help.HelpSystem; //导入依赖的package包/类
public static void displayHelp(String contextId, Object[] selected) throws CoreException {
	IContext context= HelpSystem.getContext(contextId);
	if (context != null) {
		if (selected != null && selected.length > 0) {
			context= new JavadocHelpContext(context, selected);
		}
		PlatformUI.getWorkbench().getHelpSystem().displayHelp(context);
	}
}
 

import org.eclipse.help.HelpSystem; //导入依赖的package包/类
@Override
public IContext getContext(Object target) {
	return HelpSystem.getContext(id);
}
 

import org.eclipse.help.HelpSystem; //导入依赖的package包/类
public static void setMode(int mode) {
	getInstance().mode = mode;
	HelpSystem.setShared(mode == MODE_INFOCENTER);
}