How to write node based program?
such as database management systems or nuke compositing in movie editing program that work with nodes.
i want to write a programs that need to works with nodes and connect one to another and change position of node on screen.
if can do this with wui(javascript,jquery,...) is better for me , but in (c++,java,...) i want to know how do this.
sorry about my english!!!

If you define a "node" as an object with some data content and a set of links to other nodes, all you need to do is define the methods to use the data and to change the node connections.

Look at the STL container class templates, particularly the associative and multi-map class templates for the common "node" definitions. (The obvious partial ordering would be linked-from and linked-to. The SLT is should be available from your distribution's repository.)

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thanks about your answer but i need to write a programs something like nuke compositor and database management systems that users of my programs use graphical nodes to drag&drop them connect them to each other and so on.

examples :
http://arborjs.org/
http://www.cs.umd.edu/hcil/graphvis/
i want my program get users ability to add node,delete node,connect nodes to each other and ...etc.

As far as I can see, all you need to do is create a class that defines a node with members like node.location, node.connection_list and node.contents, and then define a set of function that modify the location, contents, and connections in response to your users actions or commands, and how the "node" is displayed.

The implementation of all of that should, I hope, be obvious. The STL templates make the node class definition quite easy to do, and the graphics tool kits (QT, etc.) make the graphics programming fairly easy.

The only hard part should be planning exactly what you want in your nodes and what you want your users to be able to accomplish with those nodes. One you've done that, the rest should be standard coding.

<edit>
After I posted the above, I looked at your second reference, which - after a little digging - led to this site, where you can find open-source software for 2D interactive node manipulation. You could look at that code to see how they did it. Re-coding it in C++ would probably be fairly easy.
</edit>

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thank you! this is that i want!