Using Merapi in Processing?

stixan

in Contributed Library Questions • 3 years ago

Hi,

I want to bridge Processing and AIR. The Merapi project is just what I need. When trying to import the Merapi java library into my Processing sketch, I get this error:

Exception in thread "main" java.lang.NoClassDefFoundError: org/apache/log4j/Logger
    at merapi.Bridge.<init>(Bridge.java:360)
    at merapi.Bridge.getInstance(Bridge.java:85)
    at merapi_test.<init>(merapi_test.java:40)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:39)
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27)
    at java.lang.reflect.Constructor.newInstance(Constructor.java:501)
    at java.lang.Class.newInstance0(Class.java:350)
    at java.lang.Class.newInstance(Class.java:303)
    at processing.core.PApplet.main(PApplet.java:7252)

My Java skills aren't hardcore enough to decipher this error message...

Any help getting Merapi to work within Processing is highly appreciated, thanks!

Replies(2)

PhiLho

Re: Using Merapi in Processing?

3 years ago

The library has a dependency on another one (perhaps it is explained on the site? it can have other dependencies as well).
Here, it is the Log4j library which is used to log messages (state of the code, in general). You have to download the corresponding jar which you can find on the Apache site and install it beside your Merapi jar.

stixan

Re: Using Merapi in Processing?

3 years ago

Thanks, phi.lho. Your reply clarified the cause of the error message I was getting.

It turns out that Merapi has quite a few dependencies. While solving the dependency problems is as easy as dragging and dropping the required .jar files on my Processing sketch, I was deterred from using Merapi when I realized I had to install a truckload of .jar files. My sketch became too cluttered compared to the simple nature of the problem I was out to solve.

In the end I resorted to a more manageable low-tech solution and ended up using simple XML-files to pass information between Processing and AIR. Might not be cutting edge, but it works like a treat.

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