CMake/Modules/UseJava.cmake

# Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
# file LICENSE.rst or https://cmake.org/licensing for details.

#[=======================================================================[.rst:
UseJava
-------

This file provides support for ``Java``.  It is assumed that
:module:`FindJava` has already been loaded.  See :module:`FindJava` for
information on how to load Java into your CMake project.

Load this module in a CMake project with:

.. code-block:: cmake

  include(UseJava)

Synopsis
^^^^^^^^

.. parsed-literal::

  `Creating and Installing JARS`_
    `add_jar`_ (<target_name> [SOURCES] <source1> [<source2>...] ...)
    `install_jar`_ (<target_name> DESTINATION <destination> [COMPONENT <component>])
    `install_jni_symlink`_ (<target_name> DESTINATION <destination> [COMPONENT <component>])

  `Header Generation`_
    `create_javah`_ ((TARGET <target> | GENERATED_FILES <VAR>) CLASSES <class>... ...)

  `Exporting JAR Targets`_
    `install_jar_exports`_ (TARGETS <jars>... FILE <filename> DESTINATION <destination> ...)
    `export_jars`_ (TARGETS <jars>... [NAMESPACE <namespace>] FILE <filename>)

  `Finding JARs`_
    `find_jar`_ (<VAR> NAMES <name1> [<name2>...] [PATHS <path1> [<path2>... ENV <var>]] ...)

  `Creating Java Documentation`_
    `create_javadoc`_ (<VAR> (PACKAGES <pkg1> [<pkg2>...] | FILES <file1> [<file2>...]) ...)

Creating And Installing JARs
^^^^^^^^^^^^^^^^^^^^^^^^^^^^

.. _add_jar:

.. command:: add_jar

  Creates a jar file containing java objects and, optionally, resources:

  .. code-block:: cmake

    add_jar(<target_name>
            [SOURCES] <source1> [<source2>...] [<resource1>...]
            [RESOURCES NAMESPACE <ns1> <resource1>... [NAMESPACE <nsX> <resourceX>...]... ]
            [INCLUDE_JARS <jar1> [<jar2>...]]
            [ENTRY_POINT <entry>]
            [VERSION <version>]
            [MANIFEST <manifest>]
            [OUTPUT_NAME <name>]
            [OUTPUT_DIR <dir>]
            [GENERATE_NATIVE_HEADERS <target>
                                     [DESTINATION (<dir>|INSTALL <dir> [BUILD <dir>])]]
            )

  This command creates a ``<target_name>.jar``.  It compiles the given
  ``<source>`` files and adds the given ``<resource>`` files to
  the jar file.  Source files can be java files or listing files
  (prefixed by ``@``).  If only resource files are given then just a jar file
  is created.

  ``SOURCES``
    Compiles the specified source files and adds the result in the jar file.

    .. versionadded:: 3.4
      Support for response files, prefixed by ``@``.

  ``RESOURCES``
    .. versionadded:: 3.21

    Adds the named ``<resource>`` files to the jar by stripping the source file
    path and placing the file beneath ``<ns>`` within the jar.

    For example::

      RESOURCES NAMESPACE "/com/my/namespace" "a/path/to/resource.txt"

    results in a resource accessible via ``/com/my/namespace/resource.txt``
    within the jar.

    Resources may be added without adjusting the namespace by adding them to
    the list of ``SOURCES`` (original behavior), in this case, resource
    paths must be relative to ``CMAKE_CURRENT_SOURCE_DIR``.  Adding resources
    without using the ``RESOURCES`` parameter in out of source builds will
    almost certainly result in confusion.

    .. note::

      Adding resources via the ``SOURCES`` parameter relies upon a hard-coded
      list of file extensions which are tested to determine whether they
      compile (e.g. File.java). ``SOURCES`` files which match the extensions
      are compiled. Files which do not match are treated as resources. To
      include uncompiled resources matching those file extensions use
      the ``RESOURCES`` parameter.

  ``INCLUDE_JARS``
    The list of jars are added to the classpath when compiling the java sources
    and also to the dependencies of the target. ``INCLUDE_JARS`` also accepts
    other target names created by ``add_jar()``. For backwards compatibility,
    jar files listed as sources are ignored (as they have been since the first
    version of this module).

  ``ENTRY_POINT``
    Defines an entry point in the jar file.

  ``VERSION``
    Adds a version to the target output name.

    The following example will create a jar file with the name
    ``shibboleet-1.2.0.jar`` and will create a symlink ``shibboleet.jar``
    pointing to the jar with the version information.

    .. code-block:: cmake

      add_jar(shibboleet shibbotleet.java VERSION 1.2.0)

  ``MANIFEST``
    Defines a custom manifest for the jar.

  ``OUTPUT_NAME``
    Specify a different output name for the target.

  ``OUTPUT_DIR``
    Sets the directory where the jar file will be generated. If not specified,
    :variable:`CMAKE_CURRENT_BINARY_DIR` is used as the output directory.

  ``GENERATE_NATIVE_HEADERS``
    .. versionadded:: 3.11

    Generates native header files for methods declared as native. These files
    provide the connective glue that allow your Java and C code to interact.
    An INTERFACE target will be created for an easy usage of generated files.
    Sub-option ``DESTINATION`` can be used to specify the output directory for
    generated header files.

    This option requires, at least, version 1.8 of the JDK.

    For an optimum usage of this option, it is recommended to include module
    JNI before any call to ``add_jar()``. The produced target for native
    headers can then be used to compile C/C++ sources with the
    :command:`target_link_libraries` command.

    .. code-block:: cmake

      find_package(JNI)
      add_jar(foo foo.java GENERATE_NATIVE_HEADERS foo-native)
      add_library(bar bar.cpp)
      target_link_libraries(bar PRIVATE foo-native)

    .. versionadded:: 3.20
      ``DESTINATION`` sub-option now supports the possibility to specify
      different output directories for ``BUILD`` and ``INSTALL`` steps. If
      ``BUILD`` directory is not specified, a default directory will be used.

      To export the interface target generated by ``GENERATE_NATIVE_HEADERS``
      option, sub-option ``INSTALL`` of ``DESTINATION`` is required:

      .. code-block:: cmake

        add_jar(foo foo.java GENERATE_NATIVE_HEADERS foo-native
                             DESTINATION INSTALL include)
        install(TARGETS foo-native EXPORT native)
        install(DIRECTORY "$<TARGET_PROPERTY:foo-native,NATIVE_HEADERS_DIRECTORY>/"
                DESTINATION include)
        install(EXPORT native DESTINATION /to/export NAMESPACE foo)

  Some variables can be set to customize the behavior of ``add_jar()`` as well
  as the java compiler:

  ``CMAKE_JAVA_COMPILE_FLAGS``
    Specify additional flags to java compiler.

  ``CMAKE_JAVA_INCLUDE_PATH``
    Specify additional paths to the class path.

  ``CMAKE_JNI_TARGET``
    If the target is a JNI library, sets this boolean variable to ``TRUE`` to
    enable creation of a JNI symbolic link (see also
    :ref:`install_jni_symlink() <install_jni_symlink>`).

  ``CMAKE_JAR_CLASSES_PREFIX``
    If multiple jars should be produced from the same java source filetree,
    to prevent the accumulation of duplicate class files in subsequent jars,
    set/reset ``CMAKE_JAR_CLASSES_PREFIX`` prior to calling the ``add_jar()``:

    .. code-block:: cmake

      set(CMAKE_JAR_CLASSES_PREFIX com/redhat/foo)
      add_jar(foo foo.java)

      set(CMAKE_JAR_CLASSES_PREFIX com/redhat/bar)
      add_jar(bar bar.java)

  The ``add_jar()`` function sets the following target properties on
  ``<target_name>``:

  ``INSTALL_FILES``
    The files which should be installed.  This is used by
    :ref:`install_jar() <install_jar>`.
  ``JNI_SYMLINK``
    The JNI symlink which should be installed.  This is used by
    :ref:`install_jni_symlink() <install_jni_symlink>`.
  ``JAR_FILE``
    The location of the jar file so that you can include it.
  ``CLASSDIR``
    The directory where the class files can be found.  For example to use them
    with ``javah``.
  ``NATIVE_HEADERS_DIRECTORY``
    .. versionadded:: 3.20

    The directory where native headers are generated. Defined when option
    ``GENERATE_NATIVE_HEADERS`` is specified.

.. _install_jar:

.. command:: install_jar

  This command installs the jar file to the given destination:

  .. code-block:: cmake

   install_jar(<target_name> <destination>)
   install_jar(<target_name> DESTINATION <destination> [COMPONENT <component>])

  This command installs the ``<target_name>`` file to the given
  ``<destination>``.  It should be called in the same scope as
  :ref:`add_jar() <add_jar>` or it will fail.

  .. versionadded:: 3.4
    The second signature with ``DESTINATION`` and ``COMPONENT`` options.

  ``DESTINATION``
    Specify the directory on disk to which a file will be installed.

  ``COMPONENT``
    Specify an installation component name with which the install rule is
    associated, such as "runtime" or "development".

  The ``install_jar()`` command sets the following target properties
  on ``<target_name>``:

  ``INSTALL_DESTINATION``
    Holds the ``<destination>`` as described above, and is used by
    :ref:`install_jar_exports() <install_jar_exports>`.

.. _install_jni_symlink:

.. command:: install_jni_symlink

  Installs JNI symlinks for target generated by :ref:`add_jar() <add_jar>`:

  .. code-block:: cmake

   install_jni_symlink(<target_name> <destination>)
   install_jni_symlink(<target_name> DESTINATION <destination> [COMPONENT <component>])

  This command installs the ``<target_name>`` JNI symlinks to the given
  ``<destination>``.  It should be called in the same scope as
  :ref:`add_jar() <add_jar>` or it will fail.

  .. versionadded:: 3.4
    The second signature with ``DESTINATION`` and ``COMPONENT`` options.

  ``DESTINATION``
    Specify the directory on disk to which a file will be installed.

  ``COMPONENT``
    Specify an installation component name with which the install rule is
    associated, such as "runtime" or "development".

  Utilize the following commands to create a JNI symbolic link:

  .. code-block:: cmake

    set(CMAKE_JNI_TARGET TRUE)
    add_jar(shibboleet shibbotleet.java VERSION 1.2.0)
    install_jar(shibboleet ${LIB_INSTALL_DIR}/shibboleet)
    install_jni_symlink(shibboleet ${JAVA_LIB_INSTALL_DIR})

Header Generation
^^^^^^^^^^^^^^^^^

.. _create_javah:

.. command:: create_javah

  .. versionadded:: 3.4

  Generates C header files for java classes:

  .. code-block:: cmake

   create_javah(TARGET <target> | GENERATED_FILES <VAR>
                CLASSES <class>...
                [CLASSPATH <classpath>...]
                [DEPENDS <depend>...]
                [OUTPUT_NAME <path>|OUTPUT_DIR <path>]
                )

  .. deprecated:: 3.11
    This command will no longer be supported starting with version 10 of the JDK
    due to the `suppression of javah tool <https://openjdk.org/jeps/313>`_.
    The :ref:`add_jar(GENERATE_NATIVE_HEADERS) <add_jar>` command should be
    used instead.

  Create C header files from java classes. These files provide the connective
  glue that allow your Java and C code to interact.

  There are two main signatures for ``create_javah()``.  The first signature
  returns generated files through variable specified by the ``GENERATED_FILES``
  option.  For example:

  .. code-block:: cmake

    create_javah(GENERATED_FILES files_headers
      CLASSES org.cmake.HelloWorld
      CLASSPATH hello.jar
    )

  The second signature for ``create_javah()`` creates a target which
  encapsulates header files generation. E.g.

  .. code-block:: cmake

    create_javah(TARGET target_headers
      CLASSES org.cmake.HelloWorld
      CLASSPATH hello.jar
    )

  Both signatures share same options.

  ``CLASSES``
    Specifies Java classes used to generate headers.

  ``CLASSPATH``
    Specifies various paths to look up classes. Here ``.class`` files, jar
    files or targets created by command add_jar can be used.

  ``DEPENDS``
    Targets on which the javah target depends.

  ``OUTPUT_NAME``
    Concatenates the resulting header files for all the classes listed by
    option ``CLASSES`` into ``<path>``.  Same behavior as option ``-o`` of
    ``javah`` tool.

  ``OUTPUT_DIR``
    Sets the directory where the header files will be generated.  Same behavior
    as option ``-d`` of ``javah`` tool.  If not specified,
    :variable:`CMAKE_CURRENT_BINARY_DIR` is used as the output directory.

Exporting JAR Targets
^^^^^^^^^^^^^^^^^^^^^

.. _install_jar_exports:

.. command:: install_jar_exports

  .. versionadded:: 3.7

  Installs a target export file:

  .. code-block:: cmake

   install_jar_exports(TARGETS <jars>...
                       [NAMESPACE <namespace>]
                       FILE <filename>
                       DESTINATION <destination> [COMPONENT <component>])

  This command installs a target export file ``<filename>`` for the named jar
  targets to the given ``<destination>`` directory.  Its function is similar to
  that of :command:`install(EXPORT)`.

  ``TARGETS``
    List of targets created by :ref:`add_jar() <add_jar>` command.

  ``NAMESPACE``
    .. versionadded:: 3.9

    The ``<namespace>`` value will be prepend to the target names as they are
    written to the import file.

  ``FILE``
    Specify name of the export file.


  ``DESTINATION``
    Specify the directory on disk to which a file will be installed.

  ``COMPONENT``
    Specify an installation component name with which the install rule is
    associated, such as "runtime" or "development".

.. _export_jars:

.. command:: export_jars

  .. versionadded:: 3.7

  Writes a target export file:

  .. code-block:: cmake

   export_jars(TARGETS <jars>...
               [NAMESPACE <namespace>]
               FILE <filename>)

  This command writes a target export file ``<filename>`` for the named ``<jars>``
  targets.  Its function is similar to that of :command:`export`.

  ``TARGETS``
    List of targets created by :ref:`add_jar() <add_jar>` command.

  ``NAMESPACE``
    .. versionadded:: 3.9

    The ``<namespace>`` value will be prepend to the target names as they are
    written to the import file.

  ``FILE``
    Specify name of the export file.

Finding JARs
^^^^^^^^^^^^

.. _find_jar:

.. command:: find_jar

  Finds the specified jar file:

  .. code-block:: cmake

    find_jar(<VAR>
             <name> | NAMES <name1> [<name2>...]
             [PATHS <path1> [<path2>... ENV <var>]]
             [VERSIONS <version1> [<version2>]]
             [DOC "cache documentation string"]
            )

  This command is used to find a full path to the named jar.  A cache
  entry named by ``<VAR>`` is created to store the result of this command.
  If the full path to a jar is found the result is stored in the
  variable and the search will not repeated unless the variable is
  cleared.  If nothing is found, the result will be ``<VAR>-NOTFOUND``, and
  the search will be attempted again next time ``find_jar()`` is invoked with
  the same variable.

  ``NAMES``
    Specify one or more possible names for the jar file.

  ``PATHS``
    Specify directories to search in addition to the default locations.
    The ``ENV`` var sub-option reads paths from a system environment variable.

  ``VERSIONS``
    Specify jar versions.

  ``DOC``
    Specify the documentation string for the ``<VAR>`` cache entry.

Creating Java Documentation
^^^^^^^^^^^^^^^^^^^^^^^^^^^

.. _create_javadoc:

.. command:: create_javadoc

  Creates java documentation based on files and packages:

  .. code-block:: cmake

    create_javadoc(<VAR>
                   (PACKAGES <pkg1> [<pkg2>...] | FILES <file1> [<file2>...])
                   [SOURCEPATH <sourcepath>]
                   [CLASSPATH <classpath>]
                   [INSTALLPATH <install path>]
                   [DOCTITLE <the documentation title>]
                   [WINDOWTITLE <the title of the document>]
                   [AUTHOR (TRUE|FALSE)]
                   [USE (TRUE|FALSE)]
                   [VERSION (TRUE|FALSE)]
                   )

  The ``create_javadoc()`` command can be used to create java documentation.
  There are two main signatures for ``create_javadoc()``.

  The first signature works with package names on a path with source files:

  .. code-block:: cmake

    create_javadoc(my_example_doc
                   PACKAGES com.example.foo com.example.bar
                   SOURCEPATH "${CMAKE_CURRENT_SOURCE_DIR}"
                   CLASSPATH ${CMAKE_JAVA_INCLUDE_PATH}
                   WINDOWTITLE "My example"
                   DOCTITLE "<h1>My example</h1>"
                   AUTHOR TRUE
                   USE TRUE
                   VERSION TRUE
                  )

  The second signature for ``create_javadoc()`` works on a given list of files:

  .. code-block:: cmake

    create_javadoc(my_example_doc
                   FILES java/A.java java/B.java
                   CLASSPATH ${CMAKE_JAVA_INCLUDE_PATH}
                   WINDOWTITLE "My example"
                   DOCTITLE "<h1>My example</h1>"
                   AUTHOR TRUE
                   USE TRUE
                   VERSION TRUE
                  )

  Both signatures share most of the options. For more details please read the
  javadoc manpage.

  ``PACKAGES``
    Specify java packages.

  ``FILES``
    Specify java source files. If relative paths are specified, they are
    relative to :variable:`CMAKE_CURRENT_SOURCE_DIR`.

  ``SOURCEPATH``
    Specify the directory where to look for packages. By default,
    :variable:`CMAKE_CURRENT_SOURCE_DIR` directory is used.

  ``CLASSPATH``
    Specify where to find user class files. Same behavior as option
    ``-classpath`` of ``javadoc`` tool.

  ``INSTALLPATH``
    Specify where to install the java documentation. If you specified, the
    documentation will be installed to
    ``${CMAKE_INSTALL_PREFIX}/share/javadoc/<VAR>``.

  ``DOCTITLE``
    Specify the title to place near the top of the overview summary file.
    Same behavior as option ``-doctitle`` of ``javadoc`` tool.

  ``WINDOWTITLE``
    Specify the title to be placed in the HTML ``<title>`` tag. Same behavior
    as option ``-windowtitle`` of ``javadoc`` tool.

  ``AUTHOR``
    When value ``TRUE`` is specified, includes the ``@author`` text in the
    generated docs. Same behavior as option  ``-author`` of ``javadoc`` tool.

  ``USE``
    When value ``TRUE`` is specified, creates class and package usage pages.
    Includes one Use page for each documented class and package. Same behavior
    as option ``-use`` of ``javadoc`` tool.

  ``VERSION``
    When value ``TRUE`` is specified, includes the version text in the
    generated docs. Same behavior as option ``-version`` of ``javadoc`` tool.
#]=======================================================================]

block(SCOPE_FOR POLICIES)
cmake_policy(SET CMP0140 NEW) # For return(PROPAGATE ...)

function (__java_copy_file src dest comment)
    add_custom_command(
        OUTPUT  ${dest}
        COMMAND ${CMAKE_COMMAND} -E copy_if_different
        ARGS    ${src}
                ${dest}
        DEPENDS ${src}
        COMMENT ${comment}
        VERBATIM
        )
endfunction ()

function(__java_lcat VAR)
    foreach(_line IN LISTS ARGN)
        string(APPEND ${VAR} "${_line}\n")
    endforeach()

    set(${VAR} "${${VAR}}" PARENT_SCOPE)
endfunction()

function(__java_export_jar VAR TARGET PATH)
    get_target_property(_jarpath ${TARGET} JAR_FILE)
    get_filename_component(_jarname ${_jarpath} NAME)
    set(_target "${_jar_NAMESPACE}${TARGET}")
    __java_lcat(${VAR}
      "# Create imported target ${_target}"
      "add_library(${_target} IMPORTED STATIC)"
      "set_target_properties(${_target} PROPERTIES"
      "  IMPORTED_LOCATION \"${PATH}/${_jarname}\""
      "  JAR_FILE \"${PATH}/${_jarname}\")"
      ""
    )
    set(${VAR} "${${VAR}}" PARENT_SCOPE)
endfunction()

function(__java_copy_resource_namespaces VAR DEST JAVA_RESOURCE_FILES JAVA_RESOURCE_FILES_RELATIVE)

    set(_ns_ID "")
    set(_ns_VAL "")

    foreach(_item IN LISTS VAR)
        if(NOT _ns_ID)
            if(NOT _item STREQUAL "NAMESPACE")
                message(FATAL_ERROR "UseJava: Expecting \"NAMESPACE\", got\t\"${_item}\"")
                return()
            endif()
        endif()

        if(_item STREQUAL "NAMESPACE")
            set(_ns_VAL "")               # Prepare for next namespace
            set(_ns_ID "${_item}")
            continue()
        endif()

        if( NOT _ns_VAL)
            # we're expecting the next token to be a namespace value
            # whatever it is, we're treating it like a namespace
            set(_ns_VAL "${_item}")
            continue()
        endif()

        if(_ns_ID AND _ns_VAL)
            # We're expecting a file name, check to see if we got one
            cmake_path(ABSOLUTE_PATH _item OUTPUT_VARIABLE _test_file_name)
            if (NOT EXISTS "${_test_file_name}")
                message(FATAL_ERROR "UseJava: File does not exist:\t${_item}")
                return()
            endif()
        endif()

        cmake_path(ABSOLUTE_PATH _item OUTPUT_VARIABLE _abs_file_name)
        cmake_path(GET _item FILENAME _resource_file_name)
        set(_dest_resource_file_name "${_ns_VAL}/${_resource_file_name}" )

        __java_copy_file( ${_abs_file_name}
                          ${DEST}/${_dest_resource_file_name}
                          "Copying ${_item} to the build directory")

        list(APPEND RESOURCE_FILES_LIST           ${DEST}/${_dest_resource_file_name})
        list(APPEND RELATIVE_RESOURCE_FILES_LIST  ${_dest_resource_file_name})

    endforeach()

    set(${JAVA_RESOURCE_FILES} "${RESOURCE_FILES_LIST}" PARENT_SCOPE)
    set(${JAVA_RESOURCE_FILES_RELATIVE} "${RELATIVE_RESOURCE_FILES_LIST}" PARENT_SCOPE)
endfunction()

# define helper scripts
set(_JAVA_EXPORT_TARGETS_SCRIPT ${CMAKE_CURRENT_LIST_DIR}/UseJava/javaTargets.cmake.in)
set(_JAVA_SYMLINK_SCRIPT ${CMAKE_CURRENT_LIST_DIR}/UseJava/Symlinks.cmake)

if (CMAKE_HOST_WIN32 AND NOT CYGWIN AND CMAKE_HOST_SYSTEM_NAME MATCHES "Windows")
    set(_UseJava_PATH_SEP "$<SEMICOLON>")
else ()
    set(_UseJava_PATH_SEP ":")
endif()

function(__java_resolve_jar outvar_path path_or_tgt)
    if (TARGET "${path_or_tgt}")
        # Check if this is a target created by add_jar
        get_target_property(jarpath "${path_or_tgt}" JAR_FILE)
        set("${outvar_path}" "${jarpath}")
        if (NOT jarpath) # Some other target that we do not know how to use as a JAR
            message(SEND_ERROR "target ${path_or_tgt} is not a jar")
        endif ()
    else () # Interpreted as the path to an external JAR
        set("${outvar_path}" "${path_or_tgt}")
    endif ()
    return(PROPAGATE "${outvar_path}")
endfunction()

# Helper that processes a list of add_jar-created targets or paths to external
# JAR files and:
# - appends each item (target name or JAR path) to the list in outvar_depsraw.
# - appends the resolved JAR path to the list in outvar_depsresolved.
# If any item cannot be resolved, because it is a target name that was not
# created by add_jar, a SEND_ERROR message is raised.
function(__java_build_deplists outvar_depsraw outvar_depsresolved jars_or_targets_lst)
    foreach(item IN LISTS "${jars_or_targets_lst}")
        __java_resolve_jar(res_path "${item}")
        if (res_path) # We would get a falsy value in the error case
            list(APPEND "${outvar_depsraw}" "${item}") # Keep the original name (possibly a target) here
            list(APPEND "${outvar_depsresolved}" "${res_path}")
        endif ()
    endforeach()
    return(PROPAGATE "${outvar_depsraw}" "${outvar_depsresolved}")
endfunction()

function(add_jar _TARGET_NAME)

    set(options)  # currently there are no zero value args (aka: options)
    set(oneValueArgs "ENTRY_POINT;MANIFEST;OUTPUT_DIR;;OUTPUT_NAME;VERSION" )
    set(multiValueArgs "GENERATE_NATIVE_HEADERS;INCLUDE_JARS;RESOURCES;SOURCES" )

    cmake_parse_arguments(PARSE_ARGV 1 _add_jar
                    "${options}"
                    "${oneValueArgs}"
                    "${multiValueArgs}" )

    # In CMake < 2.8.12, add_jar used variables which were set prior to calling
    # add_jar for customizing the behavior of add_jar. In order to be backwards
    # compatible, check if any of those variables are set, and use them to
    # initialize values of the named arguments. (Giving the corresponding named
    # argument will override the value set here.)
    #
    # New features should use named arguments only.
    if(NOT DEFINED _add_jar_VERSION AND DEFINED CMAKE_JAVA_TARGET_VERSION)
        set(_add_jar_VERSION "${CMAKE_JAVA_TARGET_VERSION}")
    endif()
    if(NOT DEFINED _add_jar_OUTPUT_DIR AND DEFINED CMAKE_JAVA_TARGET_OUTPUT_DIR)
        set(_add_jar_OUTPUT_DIR "${CMAKE_JAVA_TARGET_OUTPUT_DIR}")
    endif()
    if(NOT DEFINED _add_jar_OUTPUT_NAME AND DEFINED CMAKE_JAVA_TARGET_OUTPUT_NAME)
        set(_add_jar_OUTPUT_NAME "${CMAKE_JAVA_TARGET_OUTPUT_NAME}")
        # reset
        set(CMAKE_JAVA_TARGET_OUTPUT_NAME)
    endif()
    if(NOT DEFINED _add_jar_ENTRY_POINT AND DEFINED CMAKE_JAVA_JAR_ENTRY_POINT)
        set(_add_jar_ENTRY_POINT "${CMAKE_JAVA_JAR_ENTRY_POINT}")
    endif()

    # This *should* still work if <resources1>... are included without a
    # named RESOURCES argument.  In that case, the old behavior of potentially
    # misplacing the within the Jar will behave as previously (incorrectly)
    set(_JAVA_SOURCE_FILES ${_add_jar_SOURCES} ${_add_jar_UNPARSED_ARGUMENTS})

    if (NOT DEFINED _add_jar_OUTPUT_DIR)
        set(_add_jar_OUTPUT_DIR ${CMAKE_CURRENT_BINARY_DIR})
    else()
        get_filename_component(_add_jar_OUTPUT_DIR ${_add_jar_OUTPUT_DIR} ABSOLUTE)
    endif()
    # ensure output directory exists
    file (MAKE_DIRECTORY "${_add_jar_OUTPUT_DIR}")

    if (_add_jar_ENTRY_POINT)
        set(_ENTRY_POINT_OPTION e)
        set(_ENTRY_POINT_VALUE ${_add_jar_ENTRY_POINT})
    endif ()

    if (_add_jar_MANIFEST)
        set(_MANIFEST_OPTION m)
        get_filename_component (_MANIFEST_VALUE "${_add_jar_MANIFEST}" ABSOLUTE)
    endif ()

    unset (_GENERATE_NATIVE_HEADERS)
    if (_add_jar_GENERATE_NATIVE_HEADERS)
      # Raise an error if JDK version is less than 1.8 because javac -h is not supported
      # by earlier versions.
      if (Java_VERSION VERSION_LESS 1.8)
        message (FATAL_ERROR "ADD_JAR: GENERATE_NATIVE_HEADERS is not supported with this version of Java.")
      endif()

      unset (_GENERATE_NATIVE_HEADERS_OUTPUT_DESC)

      cmake_parse_arguments (_add_jar_GENERATE_NATIVE_HEADERS "" "" "DESTINATION" ${_add_jar_GENERATE_NATIVE_HEADERS})
      if (NOT _add_jar_GENERATE_NATIVE_HEADERS_UNPARSED_ARGUMENTS)
        message (FATAL_ERROR "ADD_JAR: GENERATE_NATIVE_HEADERS: missing required argument.")
      endif()
      list (LENGTH _add_jar_GENERATE_NATIVE_HEADERS_UNPARSED_ARGUMENTS length)
      if (length GREATER 1)
        list (REMOVE_AT _add_jar_GENERATE_NATIVE_HEADERS_UNPARSED_ARGUMENTS 0)
        message (FATAL_ERROR "ADD_JAR: GENERATE_NATIVE_HEADERS: ${_add_jar_GENERATE_NATIVE_HEADERS_UNPARSED_ARGUMENTS}: unexpected argument(s).")
      endif()
      if (NOT _add_jar_GENERATE_NATIVE_HEADERS_DESTINATION)
        set (_add_jar_GENERATE_NATIVE_HEADERS_DESTINATION "${CMAKE_CURRENT_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/${_TARGET_NAME}.dir/native_headers")
      else()
        list (LENGTH _add_jar_GENERATE_NATIVE_HEADERS_DESTINATION length)
        if (NOT length EQUAL 1)
          cmake_parse_arguments (_add_jar_GENERATE_NATIVE_HEADERS_DESTINATION "" "BUILD;INSTALL" "" "${_add_jar_GENERATE_NATIVE_HEADERS_DESTINATION}")
          if (_add_jar_GENERATE_NATIVE_HEADERS_DESTINATION_UNPARSED_ARGUMENTS)
            message (FATAL_ERROR "ADD_JAR: GENERATE_NATIVE_HEADERS: DESTINATION: ${_add_jar_GENERATE_NATIVE_HEADERS_DESTINATION_UNPARSED_ARGUMENTS}: unexpected argument(s).")
          endif()
          if (NOT _add_jar_GENERATE_NATIVE_HEADERS_DESTINATION_INSTALL)
            message (FATAL_ERROR "ADD_JAR: GENERATE_NATIVE_HEADERS: DESTINATION: INSTALL sub-option is required.")
          endif()
          if (NOT _add_jar_GENERATE_NATIVE_HEADERS_DESTINATION_BUILD)
            set(_add_jar_GENERATE_NATIVE_HEADERS_DESTINATION_BUILD "${CMAKE_CURRENT_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/${_TARGET_NAME}.dir/native_headers")
          endif()
          set(_add_jar_GENERATE_NATIVE_HEADERS_DESTINATION "${_add_jar_GENERATE_NATIVE_HEADERS_DESTINATION_BUILD}")
          set(_GENERATE_NATIVE_HEADERS_OUTPUT_DESC "$<BUILD_INTERFACE:${_add_jar_GENERATE_NATIVE_HEADERS_DESTINATION_BUILD}>" "$<INSTALL_INTERFACE:${_add_jar_GENERATE_NATIVE_HEADERS_DESTINATION_INSTALL}>")
        endif()
      endif()

      set (_GENERATE_NATIVE_HEADERS_TARGET ${_add_jar_GENERATE_NATIVE_HEADERS_UNPARSED_ARGUMENTS})
      set (_GENERATE_NATIVE_HEADERS_OUTPUT_DIR "${_add_jar_GENERATE_NATIVE_HEADERS_DESTINATION}")
      set (_GENERATE_NATIVE_HEADERS -h "${_GENERATE_NATIVE_HEADERS_OUTPUT_DIR}")
      if(NOT _GENERATE_NATIVE_HEADERS_OUTPUT_DESC)
        set(_GENERATE_NATIVE_HEADERS_OUTPUT_DESC "${_GENERATE_NATIVE_HEADERS_OUTPUT_DIR}")
      endif()
    endif()

    if (LIBRARY_OUTPUT_PATH)
        set(CMAKE_JAVA_LIBRARY_OUTPUT_PATH ${LIBRARY_OUTPUT_PATH})
    else ()
        set(CMAKE_JAVA_LIBRARY_OUTPUT_PATH ${_add_jar_OUTPUT_DIR})
    endif ()

    set(CMAKE_JAVA_INCLUDE_PATH
        ${CMAKE_JAVA_INCLUDE_PATH}
        ${CMAKE_CURRENT_SOURCE_DIR}
        ${CMAKE_JAVA_OBJECT_OUTPUT_PATH}
        ${CMAKE_JAVA_LIBRARY_OUTPUT_PATH}
    )

    foreach (JAVA_INCLUDE_DIR IN LISTS CMAKE_JAVA_INCLUDE_PATH)
       string(APPEND CMAKE_JAVA_INCLUDE_PATH_FINAL "${_UseJava_PATH_SEP}${JAVA_INCLUDE_DIR}")
    endforeach()

    set(CMAKE_JAVA_CLASS_OUTPUT_PATH "${CMAKE_CURRENT_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/${_TARGET_NAME}.dir")

    set(_JAVA_TARGET_OUTPUT_NAME "${_TARGET_NAME}.jar")
    if (_add_jar_OUTPUT_NAME AND _add_jar_VERSION)
        set(_JAVA_TARGET_OUTPUT_NAME "${_add_jar_OUTPUT_NAME}-${_add_jar_VERSION}.jar")
        set(_JAVA_TARGET_OUTPUT_LINK "${_add_jar_OUTPUT_NAME}.jar")
    elseif (_add_jar_VERSION)
        set(_JAVA_TARGET_OUTPUT_NAME "${_TARGET_NAME}-${_add_jar_VERSION}.jar")
        set(_JAVA_TARGET_OUTPUT_LINK "${_TARGET_NAME}.jar")
    elseif (_add_jar_OUTPUT_NAME)
        set(_JAVA_TARGET_OUTPUT_NAME "${_add_jar_OUTPUT_NAME}.jar")
    endif ()

    set(_JAVA_CLASS_FILES)
    set(_JAVA_COMPILE_FILES)
    set(_JAVA_COMPILE_FILELISTS)
    set(_JAVA_DEPENDS)
    set(_JAVA_COMPILE_DEPENDS)
    set(_JAVA_RESOURCE_FILES)
    set(_JAVA_RESOURCE_FILES_RELATIVE)
    foreach(_JAVA_SOURCE_FILE IN LISTS _JAVA_SOURCE_FILES)
        get_filename_component(_JAVA_EXT ${_JAVA_SOURCE_FILE} EXT)
        get_filename_component(_JAVA_FILE ${_JAVA_SOURCE_FILE} NAME_WE)
        get_filename_component(_JAVA_PATH ${_JAVA_SOURCE_FILE} PATH)
        get_filename_component(_JAVA_FULL ${_JAVA_SOURCE_FILE} ABSOLUTE)

        if (_JAVA_SOURCE_FILE MATCHES "^@(.+)$")
            get_filename_component(_JAVA_FULL ${CMAKE_MATCH_1} ABSOLUTE)
            list(APPEND _JAVA_COMPILE_FILELISTS ${_JAVA_FULL})

        elseif (_JAVA_EXT MATCHES ".java")
            file(RELATIVE_PATH _JAVA_REL_BINARY_PATH ${CMAKE_CURRENT_BINARY_DIR} ${_JAVA_FULL})
            file(RELATIVE_PATH _JAVA_REL_SOURCE_PATH ${CMAKE_CURRENT_SOURCE_DIR} ${_JAVA_FULL})
            string(LENGTH ${_JAVA_REL_BINARY_PATH} _BIN_LEN)
            string(LENGTH ${_JAVA_REL_SOURCE_PATH} _SRC_LEN)
            if (_BIN_LEN LESS _SRC_LEN)
                set(_JAVA_REL_PATH ${_JAVA_REL_BINARY_PATH})
            else ()
                set(_JAVA_REL_PATH ${_JAVA_REL_SOURCE_PATH})
            endif ()
            get_filename_component(_JAVA_REL_PATH ${_JAVA_REL_PATH} PATH)

            list(APPEND _JAVA_COMPILE_FILES ${_JAVA_SOURCE_FILE})
            set(_JAVA_CLASS_FILE "${CMAKE_JAVA_CLASS_OUTPUT_PATH}/${_JAVA_REL_PATH}/${_JAVA_FILE}.class")
            set(_JAVA_CLASS_FILES ${_JAVA_CLASS_FILES} ${_JAVA_CLASS_FILE})

        elseif (_JAVA_EXT MATCHES ".jar"
                OR _JAVA_EXT MATCHES ".war"
                OR _JAVA_EXT MATCHES ".ear"
                OR _JAVA_EXT MATCHES ".sar")
            # Ignored for backward compatibility

        elseif (_JAVA_EXT STREQUAL "")
            # XXX: this was not being used after setting!
            # list(APPEND CMAKE_JAVA_INCLUDE_PATH ${JAVA_JAR_TARGET_${_JAVA_SOURCE_FILE}} ${JAVA_JAR_TARGET_${_JAVA_SOURCE_FILE}_CLASSPATH})
            list(APPEND _JAVA_DEPENDS ${JAVA_JAR_TARGET_${_JAVA_SOURCE_FILE}})

        else ()
            __java_copy_file(${CMAKE_CURRENT_SOURCE_DIR}/${_JAVA_SOURCE_FILE}
                             ${CMAKE_JAVA_CLASS_OUTPUT_PATH}/${_JAVA_SOURCE_FILE}
                             "Copying ${_JAVA_SOURCE_FILE} to the build directory")
            list(APPEND _JAVA_RESOURCE_FILES ${CMAKE_JAVA_CLASS_OUTPUT_PATH}/${_JAVA_SOURCE_FILE})
            list(APPEND _JAVA_RESOURCE_FILES_RELATIVE ${_JAVA_SOURCE_FILE})
        endif ()
    endforeach()

    if(_add_jar_RESOURCES)         # Process RESOURCES if it exists
        __java_copy_resource_namespaces("${_add_jar_RESOURCES}"
                                        ${CMAKE_JAVA_CLASS_OUTPUT_PATH}
                                        _JAVA_RESOURCE_FILES
                                        _JAVA_RESOURCE_FILES_RELATIVE)
    endif()

    # Build dependency lists and arguments for JARs in the classpath
    __java_build_deplists(_JAVA_DEPENDS _JAVA_COMPILE_DEPENDS _add_jar_INCLUDE_JARS)
    foreach (resolved_cp_item IN LISTS _JAVA_COMPILE_DEPENDS)
        string(APPEND CMAKE_JAVA_INCLUDE_PATH_FINAL "${_UseJava_PATH_SEP}${resolved_cp_item}")
    endforeach ()

    if (_JAVA_COMPILE_FILES OR _JAVA_COMPILE_FILELISTS)
        set (_JAVA_SOURCES_FILELISTS)

        if (_JAVA_COMPILE_FILES)
            # Create the list of files to compile.
            set(_JAVA_SOURCES_FILE ${CMAKE_JAVA_CLASS_OUTPUT_PATH}/java_sources)
            string(REPLACE ";" "\"\n\"" _JAVA_COMPILE_STRING "\"${_JAVA_COMPILE_FILES}\"")
            file(
              CONFIGURE
              OUTPUT "${_JAVA_SOURCES_FILE}"
              CONTENT "${_JAVA_COMPILE_STRING}\n"
              @ONLY
            )
            list (APPEND _JAVA_SOURCES_FILELISTS "@${_JAVA_SOURCES_FILE}")
        endif()
        if (_JAVA_COMPILE_FILELISTS)
            foreach (_JAVA_FILELIST IN LISTS _JAVA_COMPILE_FILELISTS)
                list (APPEND _JAVA_SOURCES_FILELISTS "@${_JAVA_FILELIST}")
            endforeach()
        endif()

        cmake_language(GET_MESSAGE_LOG_LEVEL _LOG_LEVEL)
        # Compile the java files and create a list of class files
        add_custom_command(
            # NOTE: this command generates an artificial dependency file
            OUTPUT ${CMAKE_JAVA_CLASS_OUTPUT_PATH}/java_compiled_${_TARGET_NAME}
            COMMAND ${CMAKE_COMMAND}
                -DCMAKE_JAVA_CLASS_OUTPUT_PATH=${CMAKE_JAVA_CLASS_OUTPUT_PATH}
                -DCMAKE_JAR_CLASSES_PREFIX=${CMAKE_JAR_CLASSES_PREFIX}
                -P ${CMAKE_CURRENT_FUNCTION_LIST_DIR}/UseJava/ClearClassFiles.cmake
                --log-level ${_LOG_LEVEL}
            COMMAND ${Java_JAVAC_EXECUTABLE}
                ${CMAKE_JAVA_COMPILE_FLAGS}
                -classpath "${CMAKE_JAVA_INCLUDE_PATH_FINAL}"
                -d ${CMAKE_JAVA_CLASS_OUTPUT_PATH}
                ${_GENERATE_NATIVE_HEADERS}
                ${_JAVA_SOURCES_FILELISTS}
            COMMAND ${CMAKE_COMMAND} -E touch ${CMAKE_JAVA_CLASS_OUTPUT_PATH}/java_compiled_${_TARGET_NAME}
            DEPENDS ${_JAVA_COMPILE_FILES} ${_JAVA_COMPILE_FILELISTS} ${_JAVA_COMPILE_DEPENDS} ${_JAVA_SOURCES_FILE}
            WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}
            COMMENT "Building Java objects for ${_TARGET_NAME}.jar"
            VERBATIM
        )
        add_custom_command(
            OUTPUT ${CMAKE_JAVA_CLASS_OUTPUT_PATH}/java_class_filelist
            COMMAND ${CMAKE_COMMAND}
                -DCMAKE_JAVA_CLASS_OUTPUT_PATH=${CMAKE_JAVA_CLASS_OUTPUT_PATH}
                -DCMAKE_JAR_CLASSES_PREFIX=${CMAKE_JAR_CLASSES_PREFIX}
                -P ${CMAKE_CURRENT_FUNCTION_LIST_DIR}/UseJava/ClassFilelist.cmake
            DEPENDS ${CMAKE_JAVA_CLASS_OUTPUT_PATH}/java_compiled_${_TARGET_NAME}
            WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}
            VERBATIM
        )
    else ()
        # create an empty java_class_filelist
        if (NOT EXISTS ${CMAKE_JAVA_CLASS_OUTPUT_PATH}/java_class_filelist)
            file(WRITE ${CMAKE_JAVA_CLASS_OUTPUT_PATH}/java_class_filelist "")
        endif()
    endif ()

    # create the jar file
    set(_JAVA_JAR_OUTPUT_PATH
      "${_add_jar_OUTPUT_DIR}/${_JAVA_TARGET_OUTPUT_NAME}")
    if (CMAKE_JNI_TARGET)
        add_custom_command(
            OUTPUT ${_JAVA_JAR_OUTPUT_PATH}
            COMMAND ${Java_JAR_EXECUTABLE}
                -cf${_ENTRY_POINT_OPTION}${_MANIFEST_OPTION} ${_JAVA_JAR_OUTPUT_PATH} ${_ENTRY_POINT_VALUE} ${_MANIFEST_VALUE}
                ${_JAVA_RESOURCE_FILES_RELATIVE} @java_class_filelist
            COMMAND ${CMAKE_COMMAND}
                -D_JAVA_TARGET_DIR=${_add_jar_OUTPUT_DIR}
                -D_JAVA_TARGET_OUTPUT_NAME=${_JAVA_TARGET_OUTPUT_NAME}
                -D_JAVA_TARGET_OUTPUT_LINK=${_JAVA_TARGET_OUTPUT_LINK}
                -P ${_JAVA_SYMLINK_SCRIPT}
            COMMAND ${CMAKE_COMMAND}
                -D_JAVA_TARGET_DIR=${_add_jar_OUTPUT_DIR}
                -D_JAVA_TARGET_OUTPUT_NAME=${_JAVA_JAR_OUTPUT_PATH}
                -D_JAVA_TARGET_OUTPUT_LINK=${_JAVA_TARGET_OUTPUT_LINK}
                -P ${_JAVA_SYMLINK_SCRIPT}
            DEPENDS ${_JAVA_RESOURCE_FILES} ${_JAVA_DEPENDS} ${CMAKE_JAVA_CLASS_OUTPUT_PATH}/java_class_filelist
            WORKING_DIRECTORY ${CMAKE_JAVA_CLASS_OUTPUT_PATH}
            COMMENT "Creating Java archive ${_JAVA_TARGET_OUTPUT_NAME}"
            VERBATIM
        )
    else ()
        add_custom_command(
            OUTPUT ${_JAVA_JAR_OUTPUT_PATH}
            COMMAND ${Java_JAR_EXECUTABLE}
                -cf${_ENTRY_POINT_OPTION}${_MANIFEST_OPTION} ${_JAVA_JAR_OUTPUT_PATH} ${_ENTRY_POINT_VALUE} ${_MANIFEST_VALUE}
                ${_JAVA_RESOURCE_FILES_RELATIVE} @java_class_filelist
            COMMAND ${CMAKE_COMMAND}
                -D_JAVA_TARGET_DIR=${_add_jar_OUTPUT_DIR}
                -D_JAVA_TARGET_OUTPUT_NAME=${_JAVA_TARGET_OUTPUT_NAME}
                -D_JAVA_TARGET_OUTPUT_LINK=${_JAVA_TARGET_OUTPUT_LINK}
                -P ${_JAVA_SYMLINK_SCRIPT}
            WORKING_DIRECTORY ${CMAKE_JAVA_CLASS_OUTPUT_PATH}
            DEPENDS ${_JAVA_RESOURCE_FILES} ${_JAVA_DEPENDS} ${CMAKE_JAVA_CLASS_OUTPUT_PATH}/java_class_filelist
            COMMENT "Creating Java archive ${_JAVA_TARGET_OUTPUT_NAME}"
            VERBATIM
        )
    endif ()

    # Add the target and make sure we have the latest resource files.
    add_custom_target(${_TARGET_NAME} ALL DEPENDS ${_JAVA_JAR_OUTPUT_PATH})

    set_property(
        TARGET
            ${_TARGET_NAME}
        PROPERTY
            INSTALL_FILES
                ${_JAVA_JAR_OUTPUT_PATH}
    )

    if (_JAVA_TARGET_OUTPUT_LINK)
        set_property(
            TARGET
                ${_TARGET_NAME}
            PROPERTY
                INSTALL_FILES
                    ${_JAVA_JAR_OUTPUT_PATH}
                    ${_add_jar_OUTPUT_DIR}/${_JAVA_TARGET_OUTPUT_LINK}
        )

        if (CMAKE_JNI_TARGET)
            set_property(
                TARGET
                    ${_TARGET_NAME}
                PROPERTY
                    JNI_SYMLINK
                        ${_add_jar_OUTPUT_DIR}/${_JAVA_TARGET_OUTPUT_LINK}
            )
        endif ()
    endif ()

    set_property(
        TARGET
            ${_TARGET_NAME}
        PROPERTY
            JAR_FILE
                ${_JAVA_JAR_OUTPUT_PATH}
    )

    set_property(
        TARGET
            ${_TARGET_NAME}
        PROPERTY
            CLASSDIR
                ${CMAKE_JAVA_CLASS_OUTPUT_PATH}
    )

  if (_GENERATE_NATIVE_HEADERS)
    # create an INTERFACE library encapsulating include directory for generated headers
    add_library (${_GENERATE_NATIVE_HEADERS_TARGET} INTERFACE)
    target_include_directories (${_GENERATE_NATIVE_HEADERS_TARGET} INTERFACE
      "${_GENERATE_NATIVE_HEADERS_OUTPUT_DESC}"
      ${JNI_INCLUDE_DIRS})
    set_property(TARGET ${_GENERATE_NATIVE_HEADERS_TARGET} PROPERTY NATIVE_HEADERS_DIRECTORY "${_GENERATE_NATIVE_HEADERS_OUTPUT_DIR}")
    # this INTERFACE library depends on jar generation
    add_dependencies (${_GENERATE_NATIVE_HEADERS_TARGET} ${_TARGET_NAME})

    set_property (DIRECTORY APPEND PROPERTY ADDITIONAL_CLEAN_FILES
      "${_GENERATE_NATIVE_HEADERS_OUTPUT_DIR}")
  endif()
endfunction()

function(INSTALL_JAR _TARGET_NAME)
    if (ARGC EQUAL 2)
      set (_DESTINATION ${ARGV1})
    else()
      cmake_parse_arguments(_install_jar
        ""
        "DESTINATION;COMPONENT"
        ""
        ${ARGN})
      if (_install_jar_DESTINATION)
        set (_DESTINATION ${_install_jar_DESTINATION})
      else()
        message(SEND_ERROR "install_jar: ${_TARGET_NAME}: DESTINATION must be specified.")
      endif()

      if (_install_jar_COMPONENT)
        set (_COMPONENT COMPONENT ${_install_jar_COMPONENT})
      endif()
    endif()

    get_property(__FILES
        TARGET
            ${_TARGET_NAME}
        PROPERTY
            INSTALL_FILES
    )
    set_property(
        TARGET
            ${_TARGET_NAME}
        PROPERTY
            INSTALL_DESTINATION
            ${_DESTINATION}
    )

    if (__FILES)
        install(
            FILES
                ${__FILES}
            DESTINATION
                ${_DESTINATION}
            ${_COMPONENT}
        )
    else ()
        message(SEND_ERROR "install_jar: The target ${_TARGET_NAME} is not known in this scope.")
    endif ()
endfunction()

function(INSTALL_JNI_SYMLINK _TARGET_NAME)
    if (ARGC EQUAL 2)
      set (_DESTINATION ${ARGV1})
    else()
      cmake_parse_arguments(_install_jni_symlink
        ""
        "DESTINATION;COMPONENT"
        ""
        ${ARGN})
      if (_install_jni_symlink_DESTINATION)
        set (_DESTINATION ${_install_jni_symlink_DESTINATION})
      else()
        message(SEND_ERROR "install_jni_symlink: ${_TARGET_NAME}: DESTINATION must be specified.")
      endif()

      if (_install_jni_symlink_COMPONENT)
        set (_COMPONENT COMPONENT ${_install_jni_symlink_COMPONENT})
      endif()
    endif()

    get_property(__SYMLINK
        TARGET
            ${_TARGET_NAME}
        PROPERTY
            JNI_SYMLINK
    )

    if (__SYMLINK)
        install(
            FILES
                ${__SYMLINK}
            DESTINATION
                ${_DESTINATION}
            ${_COMPONENT}
        )
    else ()
        message(SEND_ERROR "install_jni_symlink: The target ${_TARGET_NAME} is not known in this scope.")
    endif ()
endfunction()

function (find_jar VARIABLE)
    set(_jar_names)
    set(_jar_files)
    set(_jar_versions)
    set(_jar_paths
        /usr/share/java/
        /usr/local/share/java/
        ${Java_JAR_PATHS})
    set(_jar_doc "NOTSET")

    set(_state "name")

    foreach (arg IN LISTS ARGN)
        if (_state STREQUAL "name")
            if (arg STREQUAL "VERSIONS")
                set(_state "versions")
            elseif (arg STREQUAL "NAMES")
                set(_state "names")
            elseif (arg STREQUAL "PATHS")
                set(_state "paths")
            elseif (arg STREQUAL "DOC")
                set(_state "doc")
            else ()
                set(_jar_names ${arg})
                if (_jar_doc STREQUAL "NOTSET")
                    set(_jar_doc "Finding ${arg} jar")
                endif ()
            endif ()
        elseif (_state STREQUAL "versions")
            if (arg STREQUAL "NAMES")
                set(_state "names")
            elseif (arg STREQUAL "PATHS")
                set(_state "paths")
            elseif (arg STREQUAL "DOC")
                set(_state "doc")
            else ()
                set(_jar_versions ${_jar_versions} ${arg})
            endif ()
        elseif (_state STREQUAL "names")
            if (arg STREQUAL "VERSIONS")
                set(_state "versions")
            elseif (arg STREQUAL "PATHS")
                set(_state "paths")
            elseif (arg STREQUAL "DOC")
                set(_state "doc")
            else ()
                set(_jar_names ${_jar_names} ${arg})
                if (_jar_doc STREQUAL "NOTSET")
                    set(_jar_doc "Finding ${arg} jar")
                endif ()
            endif ()
        elseif (_state STREQUAL "paths")
            if (arg STREQUAL "VERSIONS")
                set(_state "versions")
            elseif (arg STREQUAL "NAMES")
                set(_state "names")
            elseif (arg STREQUAL "DOC")
                set(_state "doc")
            else ()
                set(_jar_paths ${_jar_paths} ${arg})
            endif ()
        elseif (_state STREQUAL "doc")
            if (arg STREQUAL "VERSIONS")
                set(_state "versions")
            elseif (arg STREQUAL "NAMES")
                set(_state "names")
            elseif (arg STREQUAL "PATHS")
                set(_state "paths")
            else ()
                set(_jar_doc ${arg})
            endif ()
        endif ()
    endforeach ()

    if (NOT _jar_names)
        message(FATAL_ERROR "find_jar: No name to search for given")
    endif ()

    foreach (jar_name IN LISTS _jar_names)
        foreach (version IN LISTS _jar_versions)
            set(_jar_files ${_jar_files} ${jar_name}-${version}.jar)
        endforeach ()
        set(_jar_files ${_jar_files} ${jar_name}.jar)
    endforeach ()

    find_file(${VARIABLE}
        NAMES   ${_jar_files}
        PATHS   ${_jar_paths}
        DOC     ${_jar_doc}
        NO_DEFAULT_PATH)
endfunction ()

function(create_javadoc _target)
    set(_javadoc_packages)
    set(_javadoc_files)
    set(_javadoc_sourcepath)
    set(_javadoc_classpath)
    set(_javadoc_installpath "${CMAKE_INSTALL_PREFIX}/share/javadoc")
    set(_javadoc_doctitle)
    set(_javadoc_windowtitle)
    set(_javadoc_author FALSE)
    set(_javadoc_version FALSE)
    set(_javadoc_use FALSE)

    set(_state "package")

    foreach (arg IN LISTS ARGN)
        if (_state STREQUAL "package")
            if (arg STREQUAL "PACKAGES")
                set(_state "packages")
            elseif (arg STREQUAL "FILES")
                set(_state "files")
            elseif (arg STREQUAL "SOURCEPATH")
                set(_state "sourcepath")
            elseif (arg STREQUAL "CLASSPATH")
                set(_state "classpath")
            elseif (arg STREQUAL "INSTALLPATH")
                set(_state "installpath")
            elseif (arg STREQUAL "DOCTITLE")
                set(_state "doctitle")
            elseif (arg STREQUAL "WINDOWTITLE")
                set(_state "windowtitle")
            elseif (arg STREQUAL "AUTHOR")
                set(_state "author")
            elseif (arg STREQUAL "USE")
                set(_state "use")
            elseif (arg STREQUAL "VERSION")
                set(_state "version")
            else ()
                set(_javadoc_packages ${arg})
                set(_state "packages")
            endif ()
        elseif (_state STREQUAL "packages")
            if (arg STREQUAL "FILES")
                set(_state "files")
            elseif (arg STREQUAL "SOURCEPATH")
                set(_state "sourcepath")
            elseif (arg STREQUAL "CLASSPATH")
                set(_state "classpath")
            elseif (arg STREQUAL "INSTALLPATH")
                set(_state "installpath")
            elseif (arg STREQUAL "DOCTITLE")
                set(_state "doctitle")
            elseif (arg STREQUAL "WINDOWTITLE")
                set(_state "windowtitle")
            elseif (arg STREQUAL "AUTHOR")
                set(_state "author")
            elseif (arg STREQUAL "USE")
                set(_state "use")
            elseif (arg STREQUAL "VERSION")
                set(_state "version")
            else ()
                list(APPEND _javadoc_packages ${arg})
            endif ()
        elseif (_state STREQUAL "files")
            if (arg STREQUAL "PACKAGES")
                set(_state "packages")
            elseif (arg STREQUAL "SOURCEPATH")
                set(_state "sourcepath")
            elseif (arg STREQUAL "CLASSPATH")
                set(_state "classpath")
            elseif (arg STREQUAL "INSTALLPATH")
                set(_state "installpath")
            elseif (arg STREQUAL "DOCTITLE")
                set(_state "doctitle")
            elseif (arg STREQUAL "WINDOWTITLE")
                set(_state "windowtitle")
            elseif (arg STREQUAL "AUTHOR")
                set(_state "author")
            elseif (arg STREQUAL "USE")
                set(_state "use")
            elseif (arg STREQUAL "VERSION")
                set(_state "version")
            else ()
                list(APPEND _javadoc_files ${arg})
            endif ()
        elseif (_state STREQUAL "sourcepath")
            if (arg STREQUAL "PACKAGES")
                set(_state "packages")
            elseif (arg STREQUAL "FILES")
                set(_state "files")
            elseif (arg STREQUAL "CLASSPATH")
                set(_state "classpath")
            elseif (arg STREQUAL "INSTALLPATH")
                set(_state "installpath")
            elseif (arg STREQUAL "DOCTITLE")
                set(_state "doctitle")
            elseif (arg STREQUAL "WINDOWTITLE")
                set(_state "windowtitle")
            elseif (arg STREQUAL "AUTHOR")
                set(_state "author")
            elseif (arg STREQUAL "USE")
                set(_state "use")
            elseif (arg STREQUAL "VERSION")
                set(_state "version")
            else ()
                list(APPEND _javadoc_sourcepath ${arg})
            endif ()
        elseif (_state STREQUAL "classpath")
            if (arg STREQUAL "PACKAGES")
                set(_state "packages")
            elseif (arg STREQUAL "FILES")
                set(_state "files")
            elseif (arg STREQUAL "SOURCEPATH")
                set(_state "sourcepath")
            elseif (arg STREQUAL "INSTALLPATH")
                set(_state "installpath")
            elseif (arg STREQUAL "DOCTITLE")
                set(_state "doctitle")
            elseif (arg STREQUAL "WINDOWTITLE")
                set(_state "windowtitle")
            elseif (arg STREQUAL "AUTHOR")
                set(_state "author")
            elseif (arg STREQUAL "USE")
                set(_state "use")
            elseif (arg STREQUAL "VERSION")
                set(_state "version")
            else ()
                list(APPEND _javadoc_classpath ${arg})
            endif ()
        elseif (_state STREQUAL "installpath")
            if (arg STREQUAL "PACKAGES")
                set(_state "packages")
            elseif (arg STREQUAL "FILES")
                set(_state "files")
            elseif (arg STREQUAL "SOURCEPATH")
                set(_state "sourcepath")
            elseif (arg STREQUAL "DOCTITLE")
                set(_state "doctitle")
            elseif (arg STREQUAL "WINDOWTITLE")
                set(_state "windowtitle")
            elseif (arg STREQUAL "AUTHOR")
                set(_state "author")
            elseif (arg STREQUAL "USE")
                set(_state "use")
            elseif (arg STREQUAL "VERSION")
                set(_state "version")
            else ()
                set(_javadoc_installpath ${arg})
            endif ()
        elseif (_state STREQUAL "doctitle")
            if (${arg} STREQUAL "PACKAGES")
                set(_state "packages")
            elseif (arg STREQUAL "FILES")
                set(_state "files")
            elseif (arg STREQUAL "SOURCEPATH")
                set(_state "sourcepath")
            elseif (arg STREQUAL "INSTALLPATH")
                set(_state "installpath")
            elseif (arg STREQUAL "CLASSPATH")
                set(_state "classpath")
            elseif (arg STREQUAL "WINDOWTITLE")
                set(_state "windowtitle")
            elseif (arg STREQUAL "AUTHOR")
                set(_state "author")
            elseif (arg STREQUAL "USE")
                set(_state "use")
            elseif (arg STREQUAL "VERSION")
                set(_state "version")
            else ()
                set(_javadoc_doctitle ${arg})
            endif ()
        elseif (_state STREQUAL "windowtitle")
            if (${arg} STREQUAL "PACKAGES")
                set(_state "packages")
            elseif (arg STREQUAL "FILES")
                set(_state "files")
            elseif (arg STREQUAL "SOURCEPATH")
                set(_state "sourcepath")
            elseif (arg STREQUAL "CLASSPATH")
                set(_state "classpath")
            elseif (arg STREQUAL "INSTALLPATH")
                set(_state "installpath")
            elseif (arg STREQUAL "DOCTITLE")
                set(_state "doctitle")
            elseif (arg STREQUAL "AUTHOR")
                set(_state "author")
            elseif (arg STREQUAL "USE")
                set(_state "use")
            elseif (arg STREQUAL "VERSION")
                set(_state "version")
            else ()
                set(_javadoc_windowtitle ${arg})
            endif ()
        elseif (_state STREQUAL "author")
            if (arg STREQUAL "PACKAGES")
                set(_state "packages")
            elseif (arg STREQUAL "FILES")
                set(_state "files")
            elseif (arg STREQUAL "SOURCEPATH")
                set(_state "sourcepath")
            elseif (arg STREQUAL "CLASSPATH")
                set(_state "classpath")
            elseif (arg STREQUAL "INSTALLPATH")
                set(_state "installpath")
            elseif (arg STREQUAL "DOCTITLE")
                set(_state "doctitle")
            elseif (arg STREQUAL "WINDOWTITLE")
                set(_state "windowtitle")
            elseif (arg STREQUAL "AUTHOR")
                set(_state "author")
            elseif (arg STREQUAL "USE")
                set(_state "use")
            elseif (arg STREQUAL "VERSION")
                set(_state "version")
            else ()
                set(_javadoc_author ${arg})
            endif ()
        elseif (_state STREQUAL "use")
            if (arg STREQUAL "PACKAGES")
                set(_state "packages")
            elseif (arg STREQUAL "FILES")
                set(_state "files")
            elseif (arg STREQUAL "SOURCEPATH")
                set(_state "sourcepath")
            elseif (arg STREQUAL "CLASSPATH")
                set(_state "classpath")
            elseif (arg STREQUAL "INSTALLPATH")
                set(_state "installpath")
            elseif (arg STREQUAL "DOCTITLE")
                set(_state "doctitle")
            elseif (arg STREQUAL "WINDOWTITLE")
                set(_state "windowtitle")
            elseif (arg STREQUAL "AUTHOR")
                set(_state "author")
            elseif (arg STREQUAL "USE")
                set(_state "use")
            elseif (arg STREQUAL "VERSION")
                set(_state "version")
            else ()
                set(_javadoc_use ${arg})
            endif ()
        elseif (_state STREQUAL "version")
            if (arg STREQUAL "PACKAGES")
                set(_state "packages")
            elseif (arg STREQUAL "FILES")
                set(_state "files")
            elseif (arg STREQUAL "SOURCEPATH")
                set(_state "sourcepath")
            elseif (arg STREQUAL "CLASSPATH")
                set(_state "classpath")
            elseif (arg STREQUAL "INSTALLPATH")
                set(_state "installpath")
            elseif (arg STREQUAL "DOCTITLE")
                set(_state "doctitle")
            elseif (arg STREQUAL "WINDOWTITLE")
                set(_state "windowtitle")
            elseif (arg STREQUAL "AUTHOR")
                set(_state "author")
            elseif (arg STREQUAL "USE")
                set(_state "use")
            elseif (arg STREQUAL "VERSION")
                set(_state "version")
            else ()
                set(_javadoc_version ${arg})
            endif ()
        endif ()
    endforeach ()

    set(_javadoc_builddir ${CMAKE_CURRENT_BINARY_DIR}/javadoc/${_target})
    set(_javadoc_options -d ${_javadoc_builddir})

    if (_javadoc_sourcepath)
        list(JOIN _javadoc_sourcepath "${_UseJava_PATH_SEP}" _javadoc_sourcepath)
        list(APPEND _javadoc_options -sourcepath "\"${_javadoc_sourcepath}\"")
    endif ()

    if (_javadoc_classpath)
        list(JOIN _javadoc_classpath "${_UseJava_PATH_SEP}" _javadoc_classpath)
        list(APPEND _javadoc_options -classpath "\"${_javadoc_classpath}\"")
    endif ()

    if (_javadoc_doctitle)
        list(APPEND _javadoc_options -doctitle '${_javadoc_doctitle}')
    endif ()

    if (_javadoc_windowtitle)
        list(APPEND _javadoc_options -windowtitle '${_javadoc_windowtitle}')
    endif ()

    if (_javadoc_author)
        list(APPEND _javadoc_options -author)
    endif ()

    if (_javadoc_use)
        list(APPEND _javadoc_options -use)
    endif ()

    if (_javadoc_version)
        list(APPEND _javadoc_options -version)
    endif ()

    add_custom_target(${_target}_javadoc ALL
        COMMAND ${Java_JAVADOC_EXECUTABLE}
                ${_javadoc_options}
                ${_javadoc_files}
                ${_javadoc_packages}
        WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}
    )

    install(
        DIRECTORY ${_javadoc_builddir}
        DESTINATION ${_javadoc_installpath}
    )
endfunction()

function (create_javah)
  if (Java_VERSION VERSION_GREATER_EQUAL 10)
    message (FATAL_ERROR "create_javah: not supported with this Java version. Use add_jar(GENERATE_NATIVE_HEADERS) instead.")
  elseif (Java_VERSION VERSION_GREATER_EQUAL 1.8)
    message (DEPRECATION "create_javah: this command will no longer be supported starting with version 10 of JDK. Update your project by using command add_jar(GENERATE_NATIVE_HEADERS) instead.")
  endif()

    cmake_parse_arguments(_create_javah
      ""
      "TARGET;GENERATED_FILES;OUTPUT_NAME;OUTPUT_DIR"
      "CLASSES;CLASSPATH;DEPENDS"
      ${ARGN})

    # check parameters
    if (NOT _create_javah_TARGET AND NOT _create_javah_GENERATED_FILES)
      message (FATAL_ERROR "create_javah: TARGET or GENERATED_FILES must be specified.")
    endif()
    if (_create_javah_OUTPUT_NAME AND _create_javah_OUTPUT_DIR)
      message (FATAL_ERROR "create_javah: OUTPUT_NAME and OUTPUT_DIR are mutually exclusive.")
    endif()

    if (NOT _create_javah_CLASSES)
      message (FATAL_ERROR "create_javah: CLASSES is a required parameter.")
    endif()

    set (_output_files)

    # handle javah options
    set (_javah_options)

    if (_create_javah_CLASSPATH)
      # CLASSPATH can specify directories, jar files or targets created with add_jar command
      set (_classpath)
      foreach (_path IN LISTS _create_javah_CLASSPATH)
        if (TARGET ${_path})
          get_target_property (_jar_path ${_path} JAR_FILE)
          if (_jar_path)
            list (APPEND _classpath "${_jar_path}")
            list (APPEND _create_javah_DEPENDS "${_path}")
          else()
            message(SEND_ERROR "create_javah: CLASSPATH target ${_path} is not a jar.")
          endif()
        elseif (EXISTS "${_path}")
          list (APPEND _classpath "${_path}")
          if (NOT IS_DIRECTORY "${_path}")
            list (APPEND _create_javah_DEPENDS "${_path}")
          endif()
        else()
          message(SEND_ERROR "create_javah: CLASSPATH entry ${_path} does not exist.")
        endif()
      endforeach()
      string (REPLACE ";" "${_UseJava_PATH_SEP}" _classpath "${_classpath}")
      list (APPEND _javah_options -classpath "${_classpath}")
    endif()

    if (_create_javah_OUTPUT_DIR)
      list (APPEND _javah_options -d "${_create_javah_OUTPUT_DIR}")
    endif()

    if (_create_javah_OUTPUT_NAME)
      list (APPEND _javah_options -o "${_create_javah_OUTPUT_NAME}")
      set (_output_files "${_create_javah_OUTPUT_NAME}")

      get_filename_component (_create_javah_OUTPUT_DIR "${_create_javah_OUTPUT_NAME}" DIRECTORY)
      get_filename_component (_create_javah_OUTPUT_DIR "${_create_javah_OUTPUT_DIR}" ABSOLUTE)
    endif()

    if (NOT _create_javah_OUTPUT_DIR)
      set (_create_javah_OUTPUT_DIR "${CMAKE_CURRENT_BINARY_DIR}")
    endif()

    if (NOT _create_javah_OUTPUT_NAME)
      # compute output names
      foreach (_class IN LISTS _create_javah_CLASSES)
        string (REPLACE "." "_" _c_header "${_class}")
        set (_c_header  "${_create_javah_OUTPUT_DIR}/${_c_header}.h")
        list (APPEND _output_files "${_c_header}")
      endforeach()
    endif()

    # finalize custom command arguments
    if (_create_javah_DEPENDS)
      list (INSERT _create_javah_DEPENDS 0 DEPENDS)
    endif()

    add_custom_command (OUTPUT ${_output_files}
      COMMAND "${Java_JAVAH_EXECUTABLE}" ${_javah_options} -jni ${_create_javah_CLASSES}
      ${_create_javah_DEPENDS}
      WORKING_DIRECTORY ${_create_javah_OUTPUT_DIR}
      COMMENT "Building C header files from classes...")

    if (_create_javah_TARGET)
      add_custom_target (${_create_javah_TARGET} ALL DEPENDS ${_output_files})
    endif()
    if (_create_javah_GENERATED_FILES)
      set (${_create_javah_GENERATED_FILES} ${_output_files} PARENT_SCOPE)
    endif()
endfunction()

function(export_jars)
    # Parse and validate arguments
    cmake_parse_arguments(_export_jars
      ""
      "FILE;NAMESPACE"
      "TARGETS"
      ${ARGN}
    )
    if (NOT _export_jars_FILE)
      message(SEND_ERROR "export_jars: FILE must be specified.")
    endif()
    if (NOT _export_jars_TARGETS)
      message(SEND_ERROR "export_jars: TARGETS must be specified.")
    endif()
    set(_jar_NAMESPACE "${_export_jars_NAMESPACE}")

    # Set content of generated exports file
    string(REPLACE ";" " " __targets__ "${_export_jars_TARGETS}")
    set(__targetdefs__ "")
    foreach(_target IN LISTS _export_jars_TARGETS)
        get_target_property(_jarpath ${_target} JAR_FILE)
        get_filename_component(_jarpath ${_jarpath} PATH)
        __java_export_jar(__targetdefs__ ${_target} "${_jarpath}")
    endforeach()

    # Generate exports file
    configure_file(
      ${_JAVA_EXPORT_TARGETS_SCRIPT}
      ${_export_jars_FILE}
      @ONLY
    )
endfunction()

function(install_jar_exports)
    # Parse and validate arguments
    cmake_parse_arguments(_install_jar_exports
      ""
      "FILE;DESTINATION;COMPONENT;NAMESPACE"
      "TARGETS"
      ${ARGN}
    )
    if (NOT _install_jar_exports_FILE)
      message(SEND_ERROR "install_jar_exports: FILE must be specified.")
    endif()
    if (NOT _install_jar_exports_DESTINATION)
      message(SEND_ERROR "install_jar_exports: DESTINATION must be specified.")
    endif()
    if (NOT _install_jar_exports_TARGETS)
      message(SEND_ERROR "install_jar_exports: TARGETS must be specified.")
    endif()
    set(_jar_NAMESPACE "${_install_jar_exports_NAMESPACE}")

    if (_install_jar_exports_COMPONENT)
      set (_COMPONENT COMPONENT ${_install_jar_exports_COMPONENT})
    endif()

    # Determine relative path from installed export file to install prefix
    if(IS_ABSOLUTE "${_install_jar_exports_DESTINATION}")
      file(RELATIVE_PATH _relpath
        ${_install_jar_exports_DESTINATION}
        ${CMAKE_INSTALL_PREFIX}
      )
    else()
      file(RELATIVE_PATH _relpath
        ${CMAKE_INSTALL_PREFIX}/${_install_jar_exports_DESTINATION}
        ${CMAKE_INSTALL_PREFIX}
      )
    endif()

    # Set up unique location for generated exports file
    string(SHA256 _hash "${_install_jar_exports_DESTINATION}")
    set(_tmpdir ${CMAKE_CURRENT_BINARY_DIR}/CMakeFiles/JavaExports/${_hash})

    # Set content of generated exports file
    string(REPLACE ";" " " __targets__ "${_install_jar_exports_TARGETS}")
    set(__targetdefs__ "set(_prefix \${CMAKE_CURRENT_LIST_DIR}/${_relpath})\n\n")
    foreach(_target IN LISTS _install_jar_exports_TARGETS)
        get_target_property(_dir ${_target} INSTALL_DESTINATION)
        __java_export_jar(__targetdefs__ ${_target} "\${_prefix}/${_dir}")
    endforeach()
    __java_lcat(__targetdefs__ "\nunset(_prefix)")

    # Generate and install exports file
    configure_file(
      ${_JAVA_EXPORT_TARGETS_SCRIPT}
      ${_tmpdir}/${_install_jar_exports_FILE}
      @ONLY
    )
    install(FILES ${_tmpdir}/${_install_jar_exports_FILE}
            DESTINATION ${_install_jar_exports_DESTINATION}
            ${_COMPONENT})
endfunction()

endblock()