cmake: Fix java

* fix cmake/java.cmake
* fix <cmp>/java/CMakeLists.txt
* fix examples/tests/CMakeLists.txt

ortools/constraint_solver/java/CMakeLists.txt

@@ -28,3 +28,10 @@ set_target_properties(jniconstraint_solver PROPERTIES
   SWIG_USE_TARGET_INCLUDE_DIRECTORIES ON
   POSITION_INDEPENDENT_CODE ON)
 target_link_libraries(jniconstraint_solver PRIVATE ortools::ortools)
+
+if(BUILD_TESTING)
+  file(GLOB JAVA_SRCS "*Test.java")
+  foreach(FILE_NAME IN LISTS JAVA_SRCS)
+    add_java_test(${FILE_NAME})
+  endforeach()
+endif()