--- a/Wrapping/Java/Testing/Java/CMakeLists.txt
+++ b/Wrapping/Java/Testing/Java/CMakeLists.txt
@@ -22,6 +22,8 @@ if (WIN32)
 endif ()
 set(vtk_test_classpath
   "$<TARGET_FILE:VTK::vtkjava>")
+list(APPEND vtk_test_classpath
+  ${java_classpath})
 string(REPLACE ";" "${classpath_separator}" vtk_test_classpath "${vtk_test_classpath}")
 
 add_library(vtkjava_tests STATIC