Explicitely add jchart to classpath on lcmspy launch

[gizatt]

I've encountered an issue with lcm-spy where lcm-spy spews many errors on startup, and refuses to open the structure viewer on any messages being seen (it spews similar errors when I try to open the structure viewer).

Errors look like this, though with varying classes within the jchart library:

ClassDiscoverer: java.lang.NoClassDefFoundError: info/monitorenter/gui/chart/IAxis
                 jar: /home/gizatt/lcm/build/lcm-java/lcm.jar
                 class: lcm/spy/ZoomableChartScrollWheel$5.class
``

Seems pretty clear that the cause is that the jchart library isn't being seen, even though it's in ```/usr/local/share/java``` right next to ```lcm.jar```. My naive, I-don't-know-any-java solution is attached. Is there a better way / some kind of system configuration I'm missing?

[gizatt]

This problem persists for utilities that invoke lcm-spy themselves -- e.g. bot-spy, which relies on pkg-config to supply the necessary jars to get lcm-spy to run. pkg-config doesn't specify that the jchart jar is necessary

[mwoehlke-kitware]

The .pc change appears to have been intentional, at least according to the NEWS...

LCM's autotools support is likely going away in the next (non-patch) release (see #107), and TBH I'm not all that motivated (PTC) to support pkg-config users (especially CMake projects using pkg-config), but from the comments, I guess we should also export the jchart2d jar?

[mwoehlke-kitware]

Before I hit 'merge', can you adjust the PR title to something that is not a question? Thanks!

[gizatt]

Name changed. To make sure I understand what you're saying: is pkg-config totally going away, or just not currently planned to be maintained?

[mwoehlke-kitware]

Name changed

Thanks!

is pkg-config totally going away, or just not currently planned to be maintained?

I don't expect it to go away entirely any time soon; it was thought important enough that the new CMake build infrastructure does still generate .pc files (for that matter, even the m4 macros are still installed). It's more that I am not inclined to spend much time/effort maintaining it (hence, PTC). Especially for problems affecting users that shouldn't be using pkg-config in the first place. (I assume we're talking about libbot, which — aside from the minor matter that it's effectively unmaintained ATM — uses CMake, and thus should be using the CMake package configuration and exported java targets, instead.)