Need a lot of custom JComponents, but Java just too 'slow', other Solution?

Question

Hi folks,
first of all i'll try to explain my problem (although my english is quite bad)
We're programming a tool for visualising graph algorithms (df search, strong connected components, transitive reduction etc.) For that, we got a drawing area (derived from JLayeredPane) which contains the Nodes and the Edges of a graph (for all that don't know what a graphs is, just imagine these nodes as numbered circles, and the edges as directed lines from one node to another).
Both parts (Nodes and Edges) are derived from JComponent, because a) need MouseEvents on these Components and b) we need the ability to add them to a container (like JLayeredPane)
An absolute requirement is that you can directly click on the edges (to mark them, or delete them etc)
Another point which needs to be mentioned, the edges maintain a (invisible) polygon which lies around their line, this polygon is sensitive for mouseEvents.
Now there are two main problems:
* all these edges have (due to JComponent) (possibly) huge invisible rectangles (the only thing that really matters is the line from one corner of this rect. to the other) ...so if i got lets say a graph with 10.000 edges, there are a lot of edges that overlap (nearly 10.000 :) ) ... but only the Edge-object on top receives the MouseEvent (but perhaps the user wanted to cklick a edge that lies below the top-edge!) .. at the moment, the program looks at all edges below that which received the MouseEvent and checks wether the 'mouse'click' hits a polygon, If it does, the top edge dispatches the MouseEvent to that edge. (furthermore, due to the depth-order in a Layer of a JLayeredPane, we only need to look at all edges that are really below the egde that received the mouseEvent)
This all works great for 'small' numbers of edges (approximately 1000-2000) but with a rising number of edges this attempt gets slower and slower (it takes 1-3 seconds to evaluate a single mouseclick on a Sun Ultra 5/333)
* the bigger problem is, that if i got 10k+ JComponents in a Container Java gets really slow, just adding these 10k JComps. (to the JLayeredPane) takes some minutes?! Furthermore java consumes up to 200+ MB main memory in this situation.
One solution we are currently thinking about is to implement these edges as 'pure graphics'-objects (for example the Container just draws all edges).. this probably solves problem # 2 but # 1 gets even worse (no depth-order, some more coordinates hassle)
So, i hope someone can give me a hint for this problem or someone has had a similar problem before and has a good solution? (if the problem isnt clear, just ask)

Answer 1

I worked on an application once that had a similar structure as yours, but we were only scaling up to about 1000-2000 components. The problem that we identified (and that you have, no doubt, also identified) is that you are searching all of the child components on every hit test/overlap test. What we did was to subdivide out outermost container so that it had a couple of dozen children, each of which then parented some of the original child components: this cut our search space for every hit test dramatically. We had the advantage of having collections of child componenents that we knew would not overlap so our first level containers did not overlap -- you may need your first level containers to overlap, but even with this, you'll still be able to much more quickly identify components in the immediate region that should be checked individuall.