Processing 2.2.1 Video - AbstractMethodError - GStreamer / JNA mismatch? - processing

Question

I am trying to use processing-video 2.2.1 as a library from my (Scala) project. I can run the demo capture sketches directly in the Processing IDE, but from my project I get an error that looks like a version mismatch:
Exception in thread "Animation Thread" java.lang.AbstractMethodError: com.sun.jna.Structure.getFieldOrder()Ljava/util/List;
at com.sun.jna.Structure.fieldOrder(Structure.java:868)
at com.sun.jna.Structure.getFields(Structure.java:894)
at com.sun.jna.Structure.deriveLayout(Structure.java:1042)
at com.sun.jna.Structure.calculateSize(Structure.java:966)
at com.sun.jna.Structure.calculateSize(Structure.java:933)
at com.sun.jna.Structure.allocateMemory(Structure.java:360)
at com.sun.jna.Structure.<init>(Structure.java:184)
at com.sun.jna.Structure.<init>(Structure.java:172)
at com.sun.jna.Structure.<init>(Structure.java:159)
at com.sun.jna.Structure.<init>(Structure.java:151)
at org.gstreamer.lowlevel.GObjectAPI$GTypeInstance.<init>(GObjectAPI.java:114)
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
at java.lang.reflect.Constructor.newInstance(Constructor.java:422)
at java.lang.Class.newInstance(Class.java:442)
at com.sun.jna.Structure.newInstance(Structure.java:1635)
at com.sun.jna.Structure.newInstance(Structure.java:1621)
at com.sun.jna.Structure.size(Structure.java:950)
at com.sun.jna.Native.getNativeSize(Native.java:1076)
at com.sun.jna.Structure.getNativeSize(Structure.java:1927)
at com.sun.jna.Structure.getNativeSize(Structure.java:1920)
at com.sun.jna.Structure.validateField(Structure.java:1018)
at com.sun.jna.Structure.validateFields(Structure.java:1032)
at com.sun.jna.Structure.<init>(Structure.java:179)
at com.sun.jna.Structure.<init>(Structure.java:172)
at com.sun.jna.Structure.<init>(Structure.java:159)
at com.sun.jna.Structure.<init>(Structure.java:151)
at org.gstreamer.lowlevel.GObjectAPI$GParamSpec.<init>(GObjectAPI.java:395)
at org.gstreamer.GObject.findProperty(GObject.java:656)
at org.gstreamer.GObject.set(GObject.java:87)
at processing.video.Capture.initGStreamer(Unknown Source)
at processing.video.Capture.<init>(Unknown Source)
at (my sketch)
The Maven POM file is here. I end up with the following libraries on the class path:
com.googlecode.gstreamer-java:gstreamer-java:1.5
net.java.dev.jna:jna:4.0.0
net.java.dev.jna:platform:3.4.0
org.processing:core:2.2.1
org.processing:video:2.2.1
My intuition says there is a mismatch between jna and platform - should they have the same version? That would indicate that the published POM is wrong. Which version does the Processing standalone use? Unfortunately the jars there are stripped of version information.

Answer 1

Indeed, it seems the processing POM specifies an incompatible JNA version. In sbt, I could fix this with a dependencyOverrides declaration:
def processingVersion = "2.2.1"
def gstreamerVersion = "1.5"
def jnaVersion = "3.4.0"
libraryDependencies ++= Seq(
"org.processing" % "video" % processingVersion,
"com.googlecode.gstreamer-java" % "gstreamer-java" % gstreamerVersion
)
dependencyOverrides += "net.java.dev.jna" % "jna" % jnaVersion // !

Answer 2

for gradle peeps thats:
implementation ("org.processing:core:3.3.7") {
exclude group: 'net.java.dev.jna'
}
// https://mvnrepository.com/artifact/org.processing/video
implementation ("org.processing:video:3.3.7) {
exclude group: 'net.java.dev.jna'
}
// higher jna versions have abstract Structure.getFieldOrder which gstreamer doesn't implement
implementation "net.java.dev.jna:jna:3.4.0"