Graph visualization frameworks

Question

I want to visualize a Neo4j database in a graphical application. (I'm doing this primarily as a learning exercise).

I want it to behave almost identically to the visualization in Neo4j's WebAdmin: When the graphic appears, I want to see the nodes moving around as they settle into their final locations, and I want the user to be able to click and drag node icons around the screen and have them stick where they are dropped, with the rest of the graph adjusting to account for the change.

I have two questions.

• What are the technical terms for the three requirements crudely described in the paragraph above?
• I'm a Java programmer with no experience in JavaScript, but I'm thinking that, with this project, it's time to get some - sigma.js in particular seems very powerful and relatively simple. However, ultimately this needs to be done within a Java Swing application, and while I know there are various containers I can use to embed JS/HTML content into Swing, still it seems that a pure Java solution would be ideal, and I'm curious about any frameworks that might make this possible. I'm looking into Gephi now, but it doesn't seem anywhere near as powerful or as simple to use as sigma.js. Am I wrong in this assumption?
• To summarize the second question: Which would be the better investment of my time: Learning sigma.js and the various JS frameworks (which will require me to get comfortable with JS in general), or learning to use Gephi in Java? (assuming I have a general and long-term interest in graph visualization)

Answer 1

Java visualization

Gephi does provide a toolkit for Java and Python which doesn't contains the UI modules, so unless you want to use Gephi itself to visualise your network you cannot embed its UI in your Java/Swing application as long as I know. The toolkit contains all the algorithms and plugin infrastructure so if you want to use some of their analysis tool embedded in your app you can use that, otherwise I don't think it's your case.

There are other Java options if you want for graph visualisation here: Java graph library for dynamic visualisation

About Gephi and sigmaJS

• IMHO Gephi is far more powerful than sigma.js: it has full SNA tools, multiple layouts, a data editor, exporters, plugin-systems...

• One important factor is also the size of the dataset you want to visualise: while sigmaJS can handle up to 500 nodes in the view, Gephi can layout easily 50000 nodes with GPU support as well.

• Gephi is a scientific tool made for people that don't want to code to visualise a network and it does it's job. SigmaJS is one of many JS solutions to visualise graphs on a web page.

• You can always export to sigmaJS from Gephi with a plugin.

What's better?

At the end of the story I guess the tool you are going to use will depends on:

• do you have to visualise a big dataset? -> Java solutions will win for big ones
• do you need to distribute it easily? -> Web app / SigmaJS wins for distributed
• do you want to have a full integration with your app? -> Java wins

Answer 2

The best one I've found is Keylines, but its not cheap. Gephi is OK, but the last time I looked it did not support Neo4j 2.0

If your a programmer Neo4j is open source, so you can fork the repository on Git and use that (you will have to check the licencing model before you commercialise any product though)