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Real-time Java graph / chart library? [closed]

There was an earlier thread on Java graph or chart library, where JFreeChart was found to be quite good, but, as stated in its FAQ, it's not meant for real-time rendering.

Can anyone recommend a comparable library that supports real-time rendering? Just some basic xy-rendering - for instance, getting a voltage signal from data acquisition system and plotting it as it comes (time on x-axis, voltage on y-axis).

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Joonas Pulakka Avatar asked Feb 17 '09 07:02

Joonas Pulakka


2 Answers

What the FAQ actually says is that JFreeChart doesn't support hard real-time charting, meaning that the chart isn't updated when new data arrives or at deterministic interval after it. However I have found that JFreeChart can be used for the kind of applications you are describing. You can achieve 1 update per second, which is fine. I don't think a human eye can follow something quicker than this.

If you want something more than this, I doubt you will find anything in Java (or even in another language). Operating Systems that we use aren't designed to be real time. You can't have a guaranty that they will respond in a minimum interval after an event. A tight integration with the hardware driver will be needed to show more than 1-10 frames per second.

However, if you design your application correctly, the OS will do respond quickly and your application can easily display a "real-time" graph (meaning a graph that updates once a second). Just don't use your application to shut down a valve in an emergency situation!

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kgiannakakis Avatar answered Sep 24 '22 23:09

kgiannakakis


http://www.live-graph.org/

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Jacek Ławrynowicz Avatar answered Sep 25 '22 23:09

Jacek Ławrynowicz