Use Installed jchart2d (#452)

* starting to add support for python2

* remove jchart2d

* removed python2 stuff

* note that jchart2d is a dependency

* fixed inadvertent deletion

* added libjchart2d to tests

* Revert "remove jchart2d"

This reverts commit 03cd30a.

* Use system jchart2d if available

* Update docs/content/build-instructions.md

Co-authored-by: Ian Hilt <279639+ihilt@users.noreply.github.com>

---------

Co-authored-by: Ian Hilt <279639+ihilt@users.noreply.github.com>

.github/workflows/test.yml

@@ -20,7 +20,7 @@ jobs:
 
     - name: Install Dependencies
       run: |
-        sudo apt install liblua5.3-dev lua5.3
+        sudo apt install liblua5.3-dev lua5.3 libjchart2d-java
 
     - name: Configure CMake
       run: cmake -B ${{github.workspace}}/build ${{env.CMAKE_FLAGS}} -DCMAKE_BUILD_TYPE=${{ matrix.build_type }}

docs/content/build-instructions.md

@@ -42,6 +42,7 @@ Required packages:
 
 Optional packages (e.g., for language-specific support or building documentation):
   - default-jdk
+  - libjchart2d-java # note: if not installed, jchart2d will be built from source
   - doxygen
   - liblua5.3-dev
   - lua5.3

lcm-java/CMakeLists.txt

@@ -21,7 +21,12 @@ elseif (Java_VERSION VERSION_LESS 1.9)
   endif()
 endif()
 
-add_subdirectory(jchart2d-code)
+# Use system version of jchart2d if available
+find_jar(jchart2d_JAR jchart2d)
+if(NOT jchart2d_JAR)
+  add_subdirectory(jchart2d-code)
+  set(jchart2d_JAR jchart2d)
+endif()
 
 set(lcm_java_sources
   lcm/util/JImage.java
@@ -59,7 +64,7 @@ set(lcm_java_sources
 )
 
 add_jar(lcm-java
-  INCLUDE_JARS jchart2d
+  INCLUDE_JARS ${jchart2d_JAR}
   SOURCES ${lcm_java_sources}
   OUTPUT_NAME lcm
 )