We took this patch from Gentoo to break apart the portmidi build, so that we
can disable the Java parts and cleanly disable the tests which fail to link
(possibly because they are linked before “-lportmidi” is available).  The
patch was downloaded from here:

https://gitweb.gentoo.org/repo/gentoo.git/plain/media-libs/portmidi/files/portmidi-217-cmake.patch?id=56bd759df1d0c750a065b8c845e93d5dfa6b549d

--- portmidi/CMakeLists.txt
+++ portmidi/CMakeLists.txt
@@ -9,12 +9,11 @@
   set(CMAKE_BUILD_TYPE Release CACHE STRING 
       "Semicolon-separate list of supported configuration types")
   # set default directories but don't override cached values...
-  set(CMAKE_LIBRARY_OUTPUT_DIRECTORY ${CMAKE_CACHEFILE_DIR}/${CMAKE_BUILD_TYPE}
+  set(CMAKE_LIBRARY_OUTPUT_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}
       CACHE STRING "libraries go here")
-  set(CMAKE_ARCHIVE_OUTPUT_DIRECTORY ${CMAKE_CACHEFILE_DIR}/${CMAKE_BUILD_TYPE}
+  set(CMAKE_ARCHIVE_OUTPUT_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}
       CACHE STRING "libraries go here")
-  set(CMAKE_RUNTIME_OUTPUT_DIRECTORY 
-      ${CMAKE_CACHEFILE_DIR}/${CMAKE_BUILD_TYPE}
+  set(CMAKE_RUNTIME_OUTPUT_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}
       CACHE STRING "executables go here")
 
 else(UNIX)
@@ -68,10 +67,20 @@
 include_directories(pm_common porttime)
 add_subdirectory(pm_common)
 
-add_subdirectory(pm_test)
+option(PORTMIDI_ENABLE_JAVA "Enable Java bindings support" ON)
+option(PORTMIDI_ENABLE_STATIC "Build and install static libraries" OFF)
+option(PORTMIDI_ENABLE_TEST "Build test programs" ON)
+
+if(PORTMIDI_ENABLE_TEST)
+  add_subdirectory(pm_test)
+endif(PORTMIDI_ENABLE_TEST)
 
 add_subdirectory(pm_dylib)
 
 # Cannot figure out how to make an xcode Java application with CMake
-add_subdirectory(pm_java)
+if(PORTMIDI_ENABLE_JAVA)
+  set(JAR_INSTALL_DIR share/java
+      CACHE STRING "Define directory name for jar installation")
+  add_subdirectory(pm_java)
+endif(PORTMIDI_ENABLE_JAVA)
 
--- portmidi/pm_common/CMakeLists.txt
+++ portmidi/pm_common/CMakeLists.txt
@@ -44,9 +44,6 @@
 
 # first include the appropriate system-dependent file:
 if(UNIX)
-  # add the -g switch for Linux and Mac OS X (not used in Win32)
-  set (CMAKE_C_FLAGS_DEBUG "-g ${CMAKE_C_FLAGS_DEBUG}" 
-       CACHE STRING "enable extra checks for debugging" FORCE)
   if(APPLE)
     set(MACSRC pmmacosxcm pmmac readbinaryplist finddefault)
     prepend_path(LIBSRC ../pm_mac/ ${MACSRC})
@@ -62,19 +59,23 @@
                              ${COREMIDI_LIB} ${CORESERVICES_LIB}
         CACHE INTERNAL "")
 
-    set(JAVAVM_LIB "${FRAMEWORK_PATH}/JavaVM.framework")
-    set(JAVA_INCLUDE_PATHS ${JAVAVM_LIB}/Headers)
+    if(PORTMIDI_ENABLE_JAVA)
+      set(JAVAVM_LIB "${FRAMEWORK_PATH}/JavaVM.framework")
+      set(JAVA_INCLUDE_PATHS ${JAVAVM_LIB}/Headers)
+    endif(PORTMIDI_ENABLE_JAVA)
     message(STATUS "SYSROOT: " ${CMAKE_OSX_SYSROOT})
   else(APPLE)
     # LINUX settings...
-    include(FindJNI)
-    message(STATUS "JAVA_JVM_LIB_PATH is " ${JAVA_JVM_LIB_PATH})
-    message(STATUS "JAVA_INCLUDE_PATH is " ${JAVA_INCLUDE_PATH})
-    message(STATUS "JAVA_INCLUDE_PATH2 is " ${JAVA_INCLUDE_PATH2})
-    message(STATUS "JAVA_JVM_LIBRARY is " ${JAVA_JVM_LIBRARY})
-    set(JAVA_INCLUDE_PATHS ${JAVA_INCLUDE_PATH} ${JAVA_INCLUDE_PATH2})
-    # libjvm.so is found relative to JAVA_INCLUDE_PATH:
-    set(JAVAVM_LIB ${JAVA_JVM_LIBRARY}/libjvm.so)
+    if(PORTMIDI_ENABLE_JAVA)
+      include(FindJNI)
+      message(STATUS "JAVA_JVM_LIB_PATH is " ${JAVA_JVM_LIB_PATH})
+      message(STATUS "JAVA_INCLUDE_PATH is " ${JAVA_INCLUDE_PATH})
+      message(STATUS "JAVA_INCLUDE_PATH2 is " ${JAVA_INCLUDE_PATH2})
+      message(STATUS "JAVA_JVM_LIBRARY is " ${JAVA_JVM_LIBRARY})
+      set(JAVA_INCLUDE_PATHS ${JAVA_INCLUDE_PATH} ${JAVA_INCLUDE_PATH2})
+      # libjvm.so is found relative to JAVA_INCLUDE_PATH:
+      set(JAVAVM_LIB ${JAVA_JVM_LIBRARY}/libjvm.so)
+    endif(PORTMIDI_ENABLE_JAVA)
 
     set(LINUXSRC pmlinuxalsa pmlinux finddefault)
     prepend_path(LIBSRC ../pm_linux/ ${LINUXSRC})
@@ -88,10 +89,12 @@
     # /MD is multithread DLL, /MT is multithread. Change to static:
     include(../pm_win/static.cmake)
     
-    include(FindJNI)
+    if(PORTMIDI_ENABLE_JAVA)
+      include(FindJNI)
 
-    set(JAVA_INCLUDE_PATHS ${JAVA_INCLUDE_PATH} ${JAVA_INCLUDE_PATH2})
-    # message(STATUS "JAVA_INCLUDE_PATHS: " ${JAVA_INCLUDE_PATHS})
+      set(JAVA_INCLUDE_PATHS ${JAVA_INCLUDE_PATH} ${JAVA_INCLUDE_PATH2})
+      # message(STATUS "JAVA_INCLUDE_PATHS: " ${JAVA_INCLUDE_PATHS})
+    endif(PORTMIDI_ENABLE_JAVA)
 
     set(WINSRC pmwin pmwinmm)
     prepend_path(LIBSRC ../pm_win/ ${WINSRC})
@@ -99,29 +102,43 @@
     set(PM_NEEDED_LIBS winmm.lib)
   endif(WIN32)
 endif(UNIX)
-set(JNI_EXTRA_LIBS ${PM_NEEDED_LIBS} ${JAVA_JVM_LIBRARY})
+
+if(PORTMIDI_ENABLE_JAVA)
+  set(JNI_EXTRA_LIBS ${PM_NEEDED_LIBS} ${JAVA_JVM_LIBRARY})
+endif(PORTMIDI_ENABLE_JAVA)
 
 # this completes the list of library sources by adding shared code
 list(APPEND LIBSRC pmutil portmidi)
 
 # now add the shared files to make the complete list of library sources
-add_library(portmidi-static ${LIBSRC})
-set_target_properties(portmidi-static PROPERTIES OUTPUT_NAME "portmidi_s")
-target_link_libraries(portmidi-static ${PM_NEEDED_LIBS})
-
-# define the jni library
-include_directories(${JAVA_INCLUDE_PATHS})
-
-set(JNISRC ${LIBSRC} ../pm_java/pmjni/pmjni.c)
-add_library(pmjni SHARED ${JNISRC})
-target_link_libraries(pmjni ${JNI_EXTRA_LIBS})
-set_target_properties(pmjni PROPERTIES EXECUTABLE_EXTENSION "jnilib")
+if(PORTMIDI_ENABLE_STATIC)
+  add_library(portmidi-static ${LIBSRC})
+  set_target_properties(portmidi-static PROPERTIES OUTPUT_NAME "portmidi")
+  target_link_libraries(portmidi-static ${PM_NEEDED_LIBS})
+endif(PORTMIDI_ENABLE_STATIC)
+
+if(PORTMIDI_ENABLE_JAVA)
+  # define the jni library
+  include_directories(${JAVA_INCLUDE_PATHS})
+
+  set(JNISRC ${LIBSRC} ../pm_java/pmjni/pmjni.c)
+  add_library(pmjni SHARED ${JNISRC})
+  target_link_libraries(pmjni ${JNI_EXTRA_LIBS})
+  set_target_properties(pmjni PROPERTIES EXECUTABLE_EXTENSION "jnilib")
+endif(PORTMIDI_ENABLE_JAVA)
 
 # install the libraries (Linux and Mac OS X command line)
 if(UNIX)
-  INSTALL(TARGETS portmidi-static pmjni
-    LIBRARY DESTINATION /usr/local/lib
-    ARCHIVE DESTINATION /usr/local/lib)
+  if(PORTMIDI_ENABLE_STATIC)
+    INSTALL(TARGETS portmidi-static
+      LIBRARY DESTINATION lib${LIB_SUFFIX}
+      ARCHIVE DESTINATION lib${LIB_SUFFIX})
+  endif(PORTMIDI_ENABLE_STATIC)
+  if(PORTMIDI_ENABLE_JAVA)
+    INSTALL(TARGETS pmjni
+      LIBRARY DESTINATION lib${LIB_SUFFIX}
+      ARCHIVE DESTINATION lib${LIB_SUFFIX})
+  endif(PORTMIDI_ENABLE_JAVA)
 # .h files installed by pm_dylib/CMakeLists.txt, so don't need them here
 #  INSTALL(FILES portmidi.h ../porttime/porttime.h
 #    DESTINATION /usr/local/include)
--- portmidi/pm_dylib/CMakeLists.txt
+++ portmidi/pm_dylib/CMakeLists.txt
@@ -39,9 +39,6 @@
 
 # first include the appropriate system-dependent file:
 if(UNIX)
-  # add the -g switch for Linux and Mac OS X (not used in Win32)
-  set (CMAKE_C_FLAGS_DEBUG "-g ${CMAKE_C_FLAGS_DEBUG}" 
-       CACHE STRING "enable extra checks for debugging" FORCE)
   if(APPLE)
     set(MACSRC pmmacosxcm pmmac readbinaryplist finddefault)
     prepend_path(LIBSRC ../pm_mac/ ${MACSRC})
@@ -63,7 +60,8 @@
     message(STATUS "SYSROOT: " ${CMAKE_OSX_SYSROOT})
   else(APPLE)
     # LINUX settings...
-    include(FindJNI)
+    if(PORTMIDI_ENABLE_JAVA)
+      include(FindJNI)
     # message(STATUS "JAVA_JVM_LIB_PATH is " ${JAVA_JVM_LIB_PATH})
     # message(STATUS "JAVA_INCLUDE_PATH is " ${JAVA_INCLUDE_PATH})
     # note: should use JAVA_JVM_LIB_PATH, but it is not set properly
@@ -75,11 +73,8 @@
     # JAVA_INCLUDE_PATH2; if no, then we need to make both JAVA_INCLUDE_PATH
     # and JAVA_INCLUDE_PATH2 set by user (will need clear documentation
     # because JAVA_INCLUDE_PATH2 is pretty obscure)
-    set(JAVA_INCLUDE_PATH  ${JAVA_INCLUDE_PATH-UNKNOWN}
-        CACHE STRING "where to find Java SDK include directory")
-    set(JAVA_INCLUDE_PATHS ${JAVA_INCLUDE_PATH} ${JAVA_INCLUDE_PATH}/linux)
-    # libjvm.so is found relative to JAVA_INCLUDE_PATH:
-    set(JAVAVM_LIB ${JAVA_INCLUDE_PATH}/../jre/lib/i386/client/libjvm.so)
+      set(JAVAVM_LIB ${JAVA_JVM_LIBRARY})
+    endif(PORTMIDI_ENABLE_JAVA)
 
     set(LINUXSRC pmlinuxalsa pmlinux finddefault)
     prepend_path(LIBSRC ../pm_linux/ ${LINUXSRC})
@@ -91,13 +86,15 @@
   if(WIN32)
     # /MDd is multithread debug DLL, /MTd is multithread debug
     # /MD is multithread DLL, /MT is multithread 
-    
-    include(FindJNI)
-    # note: should use JAVA_JVM_LIB_PATH, but it is not set properly
-    set(JAVAVM_LIB ${JAVA_INCLUDE_PATH}/../lib/jvm.lib)
 
-    set(JAVA_INCLUDE_PATHS ${JAVA_INCLUDE_PATH} ${JAVA_INCLUDE_PATH2})
-    # message(STATUS "JAVA_INCLUDE_PATHS: " ${JAVA_INCLUDE_PATHS})
+    if(PORTMIDI_ENABLE_JAVA)
+      include(FindJNI)
+      # note: should use JAVA_JVM_LIB_PATH, but it is not set properly
+      set(JAVAVM_LIB ${JAVA_INCLUDE_PATH}/../lib/jvm.lib)
+
+      set(JAVA_INCLUDE_PATHS ${JAVA_INCLUDE_PATH} ${JAVA_INCLUDE_PATH2})
+      # message(STATUS "JAVA_INCLUDE_PATHS: " ${JAVA_INCLUDE_PATHS})
+    endif(PORTMIDI_ENABLE_JAVA)
 
     set(WINSRC pmwin pmwinmm)
     prepend_path(LIBSRC ../pm_win/ ${WINSRC})
@@ -106,7 +103,10 @@
     # message(STATUS "JAVAVM_LIB: " ${JAVAVM_LIB})
   endif(WIN32)
 endif(UNIX)
+
+if(PORTMIDI_ENABLE_JAVA)
 set(JNI_EXTRA_LIBS ${PM_NEEDED_LIBS} ${JAVAVM_LIB})
+endif(PORTMIDI_ENABLE_JAVA)
 
 # this completes the list of library sources by adding shared code
 set(SHARED_FILES pmutil portmidi)
@@ -120,8 +120,8 @@
 # install the libraries (Linux and Mac OS X command line)
 if(UNIX)
   INSTALL(TARGETS portmidi-dynamic
-    LIBRARY DESTINATION /usr/local/lib
-    ARCHIVE DESTINATION /usr/local/lib)
+    LIBRARY DESTINATION lib${LIB_SUFFIX}
+    ARCHIVE DESTINATION lib${LIB_SUFFIX})
   INSTALL(FILES ../pm_common/portmidi.h ../porttime/porttime.h
-    DESTINATION /usr/local/include)
+    DESTINATION include)
 endif(UNIX)
--- portmidi/pm_java/CMakeLists.txt
+++ portmidi/pm_java/CMakeLists.txt
@@ -5,43 +5,24 @@
     # java not dealt with in CMake -- see pm_mac/pm_mac.xcodeproj
   else(APPLE)
     # linux
-    set(JPORTMIDICLASS JPortMidi.class JPortMidiException.class
-    		       JPortMidiApi.class)
-    set(PMDEFAULTSCLASS PmDefaultsFrame.class PmDefaults.class)
-    prepend_path(JPORTMIDICLASS2 jportmidi/ ${JPORTMIDICLASS})
-    prepend_path(PMDEFAULTSCLASS2 pmdefaults/ ${PMDEFAULTSCLASS})
-    set(PMDEFAULTS_ALL_CLASSES ${JPORTMIDICLASS2} ${PMDEFAULTSCLASS2})
-    # message(STATUS "PMDEFAULTS_ALL_CLASSES is " ${PMDEFAULTS_ALL_CLASSES})
-    add_custom_command(OUTPUT pmdefaults/PmDefaultsFrame.class
-        COMMAND javac -classpath . pmdefaults/PmDefaultsFrame.java
-	MAIN_DEPENDENCY pmdefaults/PmDefaultsFrame.java
-	DEPENDS pmdefaults/PmDefaults.java
-	WORKING_DIRECTORY pm_java)
-    add_custom_command(OUTPUT pmdefaults/PmDefaults.class
-        COMMAND javac -classpath . pmdefaults/PmDefaults.java
-	MAIN_DEPENDENCY pmdefaults/PmDefaults.java
-	DEPENDS pmdefaults/PmDefaultsFrame.java
-	WORKING_DIRECTORY pm_java)
-    add_custom_command(OUTPUT ${CMAKE_LIBRARY_OUTPUT_DIRECTORY}/pmdefaults.jar
-        COMMAND	cp pmdefaults/portmusic_logo.png .
-        COMMAND	jar cmf pmdefaults/manifest.txt pmdefaults.jar
-		pmdefaults/*.class portmusic_logo.png jportmidi/*.class
-  	COMMAND chmod +x pmdefaults/pmdefaults
-	COMMAND cp pmdefaults/pmdefaults ${CMAKE_LIBRARY_OUTPUT_DIRECTORY}
-	COMMAND mv pmdefaults.jar ${CMAKE_LIBRARY_OUTPUT_DIRECTORY}
-	COMMAND rm portmusic_logo.png
-	MAIN_DEPENDENCY pmdefaults/PmDefaults.class
-	DEPENDS ${PMDEFAULTS_ALL_CLASSES}
-	WORKING_DIRECTORY pm_java)
-    add_custom_target(pmdefaults_target ALL 
-        DEPENDS ${CMAKE_LIBRARY_OUTPUT_DIRECTORY}/pmdefaults.jar)
-    # message(STATUS "add_custom_target: pmdefaults.jar")
+	set(JAVA_CLASSES jportmidi pmdefaults)
+	add_custom_command(OUTPUT ${JAVA_CLASSES}
+		COMMAND javac -d ${CMAKE_CURRENT_BINARY_DIR} jportmidi/*.java pmdefaults/*.java
+		WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR})
+	add_custom_command(OUTPUT ${CMAKE_CURRENT_BINARY_DIR}/pmdefaults.jar
+		DEPENDS ${JAVA_CLASSES}
+		COMMAND jar cmf pmdefaults/manifest.txt ${CMAKE_CURRENT_BINARY_DIR}/pmdefaults.jar
+		-C pmdefaults portmusic_logo.png -C ${CMAKE_CURRENT_BINARY_DIR} jportmidi
+		-C ${CMAKE_CURRENT_BINARY_DIR} pmdefaults
+		WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR})
+	add_custom_target(pmdefaults.jar ALL
+		DEPENDS ${CMAKE_CURRENT_BINARY_DIR}/pmdefaults.jar)
 
     # install the libraries (Linux only)
-    INSTALL(FILES ${CMAKE_LIBRARY_OUTPUT_DIRECTORY}/pmdefaults.jar
-      DESTINATION /usr/share/java)
-    INSTALL(PROGRAMS ${CMAKE_LIBRARY_OUTPUT_DIRECTORY}/pmdefaults
-      DESTINATION /usr/local/bin)
+    INSTALL(FILES ${CMAKE_CURRENT_BINARY_DIR}/pmdefaults.jar
+      DESTINATION ${JAR_INSTALL_DIR})
+    INSTALL(PROGRAMS ${CMAKE_CURRENT_SOURCE_DIR}/pmdefaults/pmdefaults
+      DESTINATION bin)
   endif(APPLE)
 endif(UNIX)
 # In windows, use pm_java/make.bat
--- portmidi/pm_test/CMakeLists.txt
+++ portmidi/pm_test/CMakeLists.txt
@@ -12,8 +12,8 @@
 
 macro(make_a_test name)
   add_executable(${name} ${name}.c)
-  target_link_libraries(${name} portmidi-static ${PM_NEEDED_LIBS})
-  add_dependencies(${name} portmidi-static)
+  target_link_libraries(${name} portmidi ${PM_NEEDED_LIBS})
+  add_dependencies(${name} portmidi)
 endmacro(make_a_test)
 
 make_a_test(test)
