With the suggested fix we get the following outputs:

1. No java installed, error reported

   CMake Error at /usr/share/cmake-3.16/Modules/FindPackageHandleStandardArgs.cmake:146 (message):

   Could NOT find Java (missing: Java_JAVA_EXECUTABLE Java_JAR_EXECUTABLE

   Java_JAVAC_EXECUTABLE Java_JAVAH_EXECUTABLE Java_JAVADOC_EXECUTABLE)

   (Required is at least version "1.6")

   Call Stack (most recent call first):

   /usr/share/cmake-3.16/Modules/FindPackageHandleStandardArgs.cmake:393 (_FPHSA_FAILURE_MESSAGE)

   /usr/share/cmake-3.16/Modules/FindJava.cmake:332 (find_package_handle_standard_args)

   storage/connect/CMakeLists.txt:282 (FIND_PACKAGE)

2. Install openjdk-11-jdk-headless (405MB), Java found, but not JNI:

   -- Found Java: /usr/bin/java (found suitable version "11.0.18", minimum required is "1.6")

   CMake Error at /usr/share/cmake-3.16/Modules/FindPackageHandleStandardArgs.cmake:146 (message):

   Could NOT find JNI (missing: JAVA_AWT_LIBRARY JAVA_AWT_INCLUDE_PATH)

   Call Stack (most recent call first):

   /usr/share/cmake-3.16/Modules/FindPackageHandleStandardArgs.cmake:393 (_FPHSA_FAILURE_MESSAGE)

   /usr/share/cmake-3.16/Modules/FindJNI.cmake:372 (FIND_PACKAGE_HANDLE_STANDARD_ARGS)

   storage/connect/CMakeLists.txt:283 (FIND_PACKAGE)

3. Here we need default-jdk (GUI based applications) only for building the package

   -- Found Java: /usr/bin/java (found suitable version "11.0.18", minimum required is "1.6")

   -- Found JNI: /usr/lib/jvm/default-java/lib/libjawt.so

   The following features have been enabled:

   * CONNECT_LIBXML2, Support for LIBXML2 in the CONNECT storage engine

   * CONNECT_ODBC, Support for ODBC in the CONNECT storage engine

   * CONNECT_JDBC, Support for JDBC in the CONNECT storage engine

4. Feature Summary change

   -- The following REQUIRED packages have been found:

   * Curses

   * Java (required version >= 1.6)

   * JNI

5. Appendix:
   I couldn't see the value of using user defined FindJava.cmake and FindJNI.cmake files instead of default modules, so removed it as stated in 2.1 of description of MDEV.
   • Without above files, without Java we get the error:

     -- Could NOT find LibXml2 (missing: LIBXML2_LIBRARY LIBXML2_INCLUDE_DIR)

     CMake Error at /usr/share/cmake-3.16/Modules/FindPackageHandleStandardArgs.cmake:146 (message):

     Could NOT find Java (missing: Java_JAVA_EXECUTABLE Java_JAR_EXECUTABLE

     Java_JAVAC_EXECUTABLE Java_JAVAH_EXECUTABLE Java_JAVADOC_EXECUTABLE)

     (Required is at least version "1.6")

     Call Stack (most recent call first):

     /usr/share/cmake-3.16/Modules/FindPackageHandleStandardArgs.cmake:393 (_FPHSA_FAILURE_MESSAGE)

     /usr/share/cmake-3.16/Modules/FindJava.cmake:332 (find_package_handle_standard_args)

     storage/connect/CMakeLists.txt:281 (FIND_PACKAGE)

   • With above files and no Java (additional file is checked as expected):

     CMake Error at /usr/share/cmake-3.16/Modules/FindPackageHandleStandardArgs.cmake:146 (message):

     Could NOT find JNI (missing: JAVA_AWT_LIBRARY JAVA_JVM_LIBRARY

     JAVA_INCLUDE_PATH JAVA_INCLUDE_PATH2 JAVA_AWT_INCLUDE_PATH)

     Call Stack (most recent call first):

     /usr/share/cmake-3.16/Modules/FindPackageHandleStandardArgs.cmake:393 (_FPHSA_FAILURE_MESSAGE)

     /usr/share/cmake-3.16/Modules/FindJNI.cmake:372 (FIND_PACKAGE_HANDLE_STANDARD_ARGS)

     cmake/FindJNI.cmake:12 (include)

     storage/connect/CMakeLists.txt:283 (FIND_PACKAGE)

Pushed with 1d0e3d80d84c2. Thanks for review.

this broke compilation on kvm-bintar-freebsd123-amd64, kvm-bintar-freebsd130-amd64, kvm-bintar-trusty-amd64, kvm-bintar-trusty-x86, kvm-fulltest, kvm-fulltest2, kvm-rpm-rhel8-aarch64, kvm-rpm-rocky8-aarch64, winx64-debug. Additionally it broke srpm builds on kvm-rpm-rhel8-amd64, kvm-rpm-rhel8-ppc64le, kvm-rpm-rocky84-amd64, kvm-rpm-centos74-amd64-debug, kvm-rpm-centos74-amd64, kvm-rpm-alma84-amd64.

danblack it seems default-jdk (debian/ubuntu) and java-11-openjdk-devel (rhel) is not installed on builders, example of getting the compilation error on aarch

-- Performing Test ODBC_OK - Success

CMake Error at /usr/share/cmake/Modules/FindPackageHandleStandardArgs.cmake:230 (message):

  Could NOT find Java (missing: Java_JAR_EXECUTABLE Java_JAVAC_EXECUTABLE

  Java_JAVAH_EXECUTABLE Java_JAVADOC_EXECUTABLE) (found suitable version

  "1.8.0_372", minimum required is "1.6")

Call Stack (most recent call first):

  /usr/share/cmake/Modules/FindPackageHandleStandardArgs.cmake:594 (_FPHSA_FAILURE_MESSAGE)

  /usr/share/cmake/Modules/FindJava.cmake:336 (find_package_handle_standard_args)

  storage/connect/CMakeLists.txt:280 (FIND_PACKAGE)

And not sure do we need this :

   # Add file to populate CPACK_RPM_BUILDREQUIRES

    FIND_FILE(Libjni_h jni.h PATHS ${JAVA_INCLUDE_PATH})

    IF(NOT JAVA_JVM_LIBRARY_DEP)

      MESSAGE(FATAL_ERROR "No JAVA_JVM_LIBRARY_DEP set by FIND_JAVA")

    ENDIF()

    CPACK_RPM_connect-engine_PACKAGE_REQUIRES(${JAVA_JVM_LIBRARY_DEP})

serg, Daniel is off couple of days , should I revert the patch since I don't have access to buildbot machines?

revert of fix, whatever you prefer

Hi serg

• Option 1: Ideally we need bb dependency, so if possible we can disable default value https://github.com/MariaDB/server/commit/a4ad56de34cd7fd18535d21e3fa3f9f966187b52 ( bb-10.4-anel-MDEV-31230-fix-missing-dependency-option-1)
• Option 2: just revert
• Option 3: Revert with update of feature summary: https://github.com/MariaDB/server/commit/40466199ae2d8f414ae011e442b9f287b944b90a (bb-10.4-anel-MDEV-31230-option-3-revert-and-update-featuresummary) and here is additional explaination:

  - `CONNECT_JDBC` is by default set to ON, but since missing Java/JNI dependency it

  actually was never built properly on bb.

  - Additionally, all JDBC related tests in `mtr` are disabled by author

  Olivier.

  - Commit 1d0e3d8 introduced Java/JNI to be required, but

  dependecies are not installed in bb and we broke the tree with the

  change.

  - Introducing change of default value of cached cmake variable `CONNECT_JDBC`

  from `ON`->`OFF` is not forwards compatible change, and as such I

  cannot be accepted(?).

  - This commit reverts commit 1d0e3d8

  but is updating description of missing Java/JNI dependency for cmake's

  feature summary.

• Option 4: Remove required package
  https://github.com/MariaDB/server/commit/bfdf26ba5f913fa7e8b75aed871bf13c6ec190a5 (bb-10.4-anel-MDEV-31230-option-4-remove-required)

-- The following features have been disabled:

 * CONNECT_JDBC, Support for JDBC in the CONNECT storage engine - Missing JAVA/JNI

-- The following OPTIONAL packages have not been found:

 * Java (required version >= 1.6)

 * JNI

# Rerun:

-- Could NOT find Java (missing: Java_JAR_EXECUTABLE Java_JAVAC_EXECUTABLE Java_JAVADOC_EXECUTABLE) (found suitable version "11.0.19", minimum required is "1.6")

-- Could NOT find JNI (missing: JAVA_INCLUDE_PATH JAVA_INCLUDE_PATH2 JAVA_AWT_INCLUDE_PATH) 

I would go with Option 4.

removing FindJava and FindJNI wrappers was wrong too, they have a purpose (fix a specific issue in cmake's files) and this issue wasn't fixed in cmake yet (as of 3.26.3)

and cmake was not "printing wrong information about variable CONNECT_JDBC", there is no variable CONNECT_JDBC. There is a user-configurable setting CONNECT_WITH_JDBC which convey's user intention to enable the feature. It is ON by default. And there's a feature tag CONNECT_JDBC that shows in the summary whether the feature was actually enabled.

As such there's no bug here, so reverting.

If you want CONNECT_WITH_JDBC=ON to mean "absolutely enable JDBC or abort", then you cannot have it ON by default. Then you change CONNECT_WITH_JDBC to be a 3-value variable ON/OFF/AUTO with the default to AUTO. We have many variables like that: WITH_NUMA, MYSQL_MAINTAINER_MODE, ENABLED_LOCAL_INFILE, WITH_SAFEMALLOC, TRASH_FREED_MEMORY, WITH_INNODB_xxx, WITH_ROCKSDB_xxx, PLUGIN_xxx