Develop Reference

Why is my shared library (dll) not getting linked with the stdc++-6.dll properly?

So I was trying to build and load a dll into a Java application using the Jni interface, and basically I've used a few libraries consisting of the Win32 API.
The build seems to be fine, everything built and linked. But I'm not able to figure out how is the stdc++-6.dll is not getting dynamically (shared) linked properly, while other things do according to the dependency manager as shown.
If I try to load the dll into the java application, I get
java.lang.UnsatisfiedLinkError: C:\<path-to-dll>\libKeyboardKtx64.dll: %1 is not a valid Win32 application
I tried to do a static build (just to know not actually want a static build), but then it says
java.lang.UnsatisfiedLinkError: C:\<path-to-dll>\libKeyboardKtx64.dll: Can't find dependent libraries.
Referencing a few questions in SO, I tried debugging
JNI C++ DLL - 'UnsatisfiedLinkError: %1 is not a valid Win32 application'
JNI %1 is not a valid Win32 application
java.io.IOException: %1 is not a valid Win32 application
Neither help, because I've did everything correctly I guess, built 64-bit dll, and trying to load it in a 64-bit Java-VM and already the dependencies inspector shows all linked libraries are 64-bit as well.
I also checked this unanswered question, it also admits the problem happens when the dll tries to reference the std lib or indirectly std:: interface, I haven't used any of them, but probably the windows libraries are using them indirectly (if I pass -nostdlib compilation fails with unresolved reference of few symbols)
For the diagnosis, I'm attaching the Cmake file I used to build the dll and build output (from the CLI):
cmake_minimum_required(VERSION 3.10)
project(KeyboardKt)
set(CMAKE_CXX_STANDARD 11)
set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -s")
set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -s")
option(ARCH "architecture")
add_definitions(-D_WIN32_WINNT=0x600)
include_directories($ENV{JNI_HEADERS_DIR})
include_directories("../../generated/jni")
include_directories("../../../nativeCommon/windows")
add_library(
KeyboardKt${ARCH} SHARED
JvmKeyboardHandler.cpp
)
== Using MXE wrapper: /usr/src/mxe/usr/bin/x86_64-w64-mingw32.shared-cmake
- cmake version 3.19.2
- warnings for unused CMAKE_POLICY_DEFAULT variables can be ignored
== Using MXE toolchain: /usr/src/mxe/usr/x86_64-w64-mingw32.shared/share/cmake/mxe-conf.cmake
== Using MXE runresult: /usr/src/mxe/usr/share/cmake/modules/TryRunResults.cmake
== Adding "-DCMAKE_BUILD_TYPE=Release"
loading initial cache file /usr/src/mxe/usr/share/cmake/modules/TryRunResults.cmake
-- The C compiler identification is GNU 10.2.0
-- The CXX compiler identification is GNU 10.2.0
-- Detecting C compiler ABI info
-- Detecting C compiler ABI info - done
-- Check for working C compiler: /usr/src/mxe/usr/bin/x86_64-w64-mingw32.shared-gcc - skipped
-- Detecting C compile features
-- Detecting C compile features - done
-- Detecting CXX compiler ABI info
-- Detecting CXX compiler ABI info - done
-- Check for working CXX compiler: /usr/src/mxe/usr/bin/x86_64-w64-mingw32.shared-g++ - skipped
-- Detecting CXX compile features
-- Detecting CXX compile features - done
-- Configuring done
-- Generating done
-- Build files have been written to: /work/project/build/tmp/compile-jni-windows-x64
== Using MXE wrapper: /usr/src/mxe/usr/bin/x86_64-w64-mingw32.shared-cmake
== Skip using MXE toolchain: /usr/src/mxe/usr/x86_64-w64-mingw32.shared/share/cmake/mxe-conf.cmake
Scanning dependencies of target KeyboardKtx64
[ 50%] Building CXX object CMakeFiles/KeyboardKtx64.dir/JvmKeyboardHandler.cpp.obj
[100%] Linking CXX shared library libKeyboardKtx64.dll
[100%] Built target KeyboardKtx64

So I finally figured out the problem, special thanks to #zero9178 which helped me alot.
I actually had 32-bit version of the libstdc++-6.dll on the PATH which was installed by the official build of MinGW so adding a 64-bit from other sources seems to work.
I had only the new keyword depends on that library as I used to inspect it with the dependency walker. So instead of including the whole library (of 2MB in size), as all the C++ features are available out of the std-lib I just used the malloc and the new placement operator from the #include <new> whose definition is present in the MSVCRT.dll (bundled in windows).
So there is no conflict or need to statically link to (or bundle) such a large header just to use some of the keywords/functions from it. Now I was able to produce as small as 14Kb still able to use the C++ features and libraries. Although its not a good advice to use the new placement operator, I used it since single operator was the only one need.

CMake could not find JNI

I created a new Android Studio Project with C++ support and did not add anything to it. The project builds, compiles and runs with CMake. I then added the following two lines of code to CMakeLists.txt at the bottom of the file and I get a CMake build error.
find_package(Java COMPONENTS Development) # Line 47
find_package(JNI REQUIRED) # Line 48
And this is the error I get when building the project
-- Found Java: /usr/lib/jvm/java-10-oracle/bin/java (found version "10.0.1") found components: Development
-- Configuring incomplete, errors occurred!
CMake Error at /home/xxxxx/Android/Sdk/cmake/3.6.4111459/share/cmake-3.6/Modules/FindPackageHandleStandardArgs.cmake:148 (message):
Could NOT find JNI (missing: JAVA_AWT_LIBRARY JAVA_JVM_LIBRARY
See also "/home/xxxxx/AndroidStudioProjects/MyApplication/app/.externalNativeBuild/cmake/release/x86_64/CMakeFiles/CMakeOutput.log".
JAVA_INCLUDE_PATH2 JAVA_AWT_INCLUDE_PATH)
Call Stack (most recent call first):
/home/xxxxxx/Android/Sdk/cmake/3.6.4111459/share/cmake-3.6/Modules/FindPackageHandleStandardArgs.cmake:388 (_FPHSA_FAILURE_MESSAGE)
/home/xxxxxx/Android/Sdk/cmake/3.6.4111459/share/cmake-3.6/Modules/FindJNI.cmake:314 (FIND_PACKAGE_HANDLE_STANDARD_ARGS)
CMakeLists.txt:48 (find_package)
External native generate JSON release: JSON generation completed with problems
CMake runs when being called form the command line, but fails inside Android Studio for some reason and I am not sure why.
EDIT 1
Here is the CMakeOutput.log file
EDIT 2
This is all that is in CMakeLists.txt file. It compiles in cmd with the command cmake.
cmake_minimum_required(VERSION 3.4.1)
find_package(Java COMPONENTS Development)
find_package(JNI REQUIRED)
This is the cmd output
E:\Users\xxxxx\AndroidStudioProjects\MyApplication\app\build>cmake ..
-- Configuring done
-- Generating done
-- Build files have been written to: E:/Users/xxxxx/AndroidStudioProjects/MyApplication/app/build
When I try to add it compile it in Android Studio using gradle I get the following error on Windows 10 pro 64 bit
Microsoft Windows [Version 10.0.17134.112]
(c) 2018 Microsoft Corporation. All rights reserved.
E:\Users\xxxxx\AndroidStudioProjects\MyApplication>gradlew build --stacktrace
> Task :app:generateJsonModelDebug
External native generate JSON debug: starting JSON generation
External native generate JSON debug: using platform version 24 for ABI ARMEABI_V7A and min SDK version 24
External native generate JSON debug: noticing that build file 'E:\Users\xxxxx\AndroidStudioProjects\MyApplication\app\CMakeLists.txt' is out of date with respect to E:\Users\xxxxx\AndroidStudioProjects\MyApplication\app\.extern
alNativeBuild\cmake\debug\armeabi-v7a\android_gradle_build.json
External native generate JSON debug: rebuilding JSON E:\Users\xxxxx\AndroidStudioProjects\MyApplication\app\.externalNativeBuild\cmake\debug\armeabi-v7a\android_gradle_build.json due to:
External native generate JSON debug: - a dependent build file changed
External native generate JSON debug: keeping json folder 'E:\Users\xxxxx\AndroidStudioProjects\MyApplication\app\.externalNativeBuild\cmake\debug\armeabi-v7a' but regenerating project
External native generate JSON debug: executing cmake Executable : E:\Android\SDK\cmake\3.6.4111459\bin\cmake.exe
arguments :
-HE:\Users\xxxxx\AndroidStudioProjects\MyApplication\app
-BE:\Users\xxxxx\AndroidStudioProjects\MyApplication\app\.externalNativeBuild\cmake\debug\armeabi-v7a
-DANDROID_ABI=armeabi-v7a
-DANDROID_PLATFORM=android-24
-DCMAKE_LIBRARY_OUTPUT_DIRECTORY=E:\Users\xxxxx\AndroidStudioProjects\MyApplication\app\build\intermediates\cmake\debug\obj\armeabi-v7a
-DCMAKE_BUILD_TYPE=Debug
-DANDROID_NDK=E:\Android\SDK\ndk-bundle
-DCMAKE_CXX_FLAGS=
-DCMAKE_TOOLCHAIN_FILE=E:\Android\SDK\ndk-bundle\build\cmake\android.toolchain.cmake
-DCMAKE_MAKE_PROGRAM=E:\Android\SDK\cmake\3.6.4111459\bin\ninja.exe
-GAndroid Gradle - Ninja
jvmArgs :
CMake Error at E:/Android/SDK/cmake/3.6.4111459/share/cmake-3.6/Modules/FindPackageHandleStandardArgs.cmake:148 (message):
Could NOT find JNI (missing: JAVA_AWT_LIBRARY JAVA_JVM_LIBRARY
JAVA_INCLUDE_PATH2 JAVA_AWT_INCLUDE_PATH)
Call Stack (most recent call first):
E:/Android/SDK/cmake/3.6.4111459/share/cmake-3.6/Modules/FindPackageHandleStandardArgs.cmake:388 (_FPHSA_FAILURE_MESSAGE)
E:/Android/SDK/cmake/3.6.4111459/share/cmake-3.6/Modules/FindJNI.cmake:314 (FIND_PACKAGE_HANDLE_STANDARD_ARGS)
CMakeLists.txt:4 (find_package)
-- Configuring incomplete, errors occurred!
See also "E:/Users/xxxxx/AndroidStudioProjects/MyApplication/app/.externalNativeBuild/cmake/debug/armeabi-v7a/CMakeFiles/CMakeOutput.log".

Could NOT find JNI (missing: JAVA_AWT_LIBRARY JAVA_JVM_LIBRARY
Solved with
sudo apt-get install -y openjdk-8-jdk
sudo apt-get install -y default-jdk
export JAVA_HOME=/usr/lib/jvm/java-8-openjdk-amd64

As the CMake version bundled with Android tries to tell you, it can't find the JNI package because some parts were missing:
missing: JAVA_AWT_LIBRARY JAVA_JVM_LIBRARY JAVA_INCLUDE_PATH2 JAVA_AWT_INCLUDE_PATH
Checking the documentation for FindJNI (https://cmake.org/cmake/help/latest/module/FindJNI.html) these variables are set to the locations of libraries and headers not shipped with the Android version of JNI (to little surprise, Android does not included the AWT library for instance).
When running find_package(JNI REQUIRED), the FindJNI code checks if these variables are set and if not, issues an error.
A workaround is to set these variables yourself, before calling find_package:
# We are only interested in finding jni.h: we do not care about extended JVM
# functionality or the AWT library.
set(JAVA_AWT_LIBRARY NotNeeded)
set(JAVA_JVM_LIBRARY NotNeeded)
set(JAVA_INCLUDE_PATH2 NotNeeded)
set(JAVA_AWT_INCLUDE_PATH NotNeeded)
find_package(JNI REQUIRED)
Be aware though, that your code will only be able to use jni.h and its functionality: if it tries to access any other part of the JNI package it will fail (probably at compile time) because essentially, you have tricked CMake into thinking that the entire package was found, when in reality only a part of it exists in the Android setup.

I found a solution that works for me:
cmake_minimum_required(VERSION 3.10)
project("ktaglib")
set(JAVA_AWT_LIBRARY "$ENV{JAVA_HOME}/lib/libjawt.so")
set(JAVA_JVM_LIBRARY "$ENV{JAVA_HOME}/lib/server/libjvm.so")
set(JAVA_INCLUDE_PATH "$ENV{JAVA_HOME}/include")
set(JAVA_INCLUDE_PATH2 "$ENV{JAVA_HOME}/include/linux")
set(JAVA_AWT_INCLUDE_PATH "$ENV{JAVA_HOME}/include")
find_package(JNI REQUIRED)
You must set the environment variable JAVA_HOME="/usr/lib/jvm/java-11-openjdk-amd64" beforehand.
More info: https://github.com/dockcross/dockcross/issues/576

Same on alpine:edge docker image, fixed using:
ENV JAVA_HOME=/usr/lib/jvm/java-1.8-openjdk
RUN apk add --no-cache openjdk8
ref: https://pkgs.alpinelinux.org/contents?branch=edge&name=openjdk8&arch=x86_64&repo=community

Smart can't install...no package provides shared object file

Problem
I'm attempting to create a Bitbake recipe which will install Oracle JRE 8 onto my target OS.
I've tried to use metadata from meta-oracle-java, but had some difficulties due to one of the .inc files which are provided for general JREs has a JRE-7-specific URI.
I've changed some of the metadata from meta-oracle-java and created my own recipe to do this install.
Tests
A Build of the JRE Recipe by Itself
When building the recipe by itself:
bitbake oracle-jse-jre
The build completes without error. I've added a dependency on libav into the oracle-jse-jre recipe, so I can do the following from TMPDIR:
$ find . -name libavformat*so
./work/core2-64-poky-linux/libav/9.18-r0/sysroot-destdir/usr/lib/libavformat.so.54.20.4
./work/core2-64-poky-linux/libav/9.18-r0/sysroot-destdir/usr/lib/libavformat.so
./work/core2-64-poky-linux/libav/9.18-r0/sysroot-destdir/usr/lib/libavformat.so.54
./sysroots/genericx86-64/usr/lib/libavformat.so.54.20.4
./sysroots/genericx86-64/usr/lib/libavformat.so
./sysroots/genericx86-64/usr/lib/libavformat.so.54
Runtime Dependency Success
If I add the default package from the oracle-jse-jre recipe to RDEPENDS_${PN} of another recipe xenoros_0.1.bb, I can run bitbake xenoros and build without errors.
Core Image Failure
If I add xenoros to the IMAGE_INSTALL variable of a core-image-xenoros, the build fails with the following error:
ERROR: Unable to install packages. Command '/home/presslertj/yocto-OS/poky-jethro-build/build/tmp/sysroots/x86_64-linux/usr/bin/smart --log-level=warning --data-dir=/home/presslertj/yocto-OS/poky-jethro-build/build/tmp/work/genericx86_64-poky-linux/core-image-my-server/1.0-r0/rootfs/var/lib/smart install -y message-generation#core2_64 catkin#core2_64 python-distutils#core2_64 ldd#core2_64 xenoros#core2_64 rosgraph#core2_64 gedit#core2_64 actionlib#core2_64 python-compression#core2_64 dhcp-server#core2_64 libpthread-stubs#core2_64 tf2#core2_64 python-email#core2_64 catkin-dev#core2_64 git#core2_64 rosbash#core2_64 python-json#core2_64 python-wstool#core2_64 connman#core2_64 ros-config#core2_64 packagegroup-core-boot#genericx86_64 libsdl-1.2-0#core2_64 rosjava#core2_64 quagga#core2_64 nginx#core2_64 rospy#core2_64 apt#core2_64 libc6#core2_64 netcat#core2_64 shadow#core2_64 bash#core2_64 roscpp#core2_64 roslaunch#core2_64 run-postinsts#all python-rosinstall#core2_64 elfutils#core2_64 openssl#core2_64 font-alias#all gradle#core2_64 python-catkin-pkg#core2_64 catkin-runtime#core2_64 catkin-runtime-dev#core2_64 pciutils#core2_64 base-passwd#core2_64' returned 1:
Loading cache...
Updating cache... ######################################## [100%]
Computing transaction...error: Can't install oracle-jse-jre-1.8.0-u77r0#core2_64: no package provides libavformat.so.53(LIBAVFORMAT_53)(64bit)
ERROR: Function failed: do_rootfs
ERROR: Logfile of failure stored in: /home/presslertj/yocto-OS/poky-jethro-build/build/tmip/work/genericx86_64-poky-linux/core-image-my-server/1.0-r0/temp/log.do_rootfs.22073
ERROR: Task 7 (/home/presslertj/yocto-OS/poky-jethro-build/meta-myLayer/recipes-core/images/core-image-my-server.bb, do_rootfs) failed with exit code '1'
Looking inside TMPDIR, I can find this:
/sysroots/genericx86-64/usr/lib/libavformat.so.54
It seems there's a version mismatch, where smart expects version 53, but 54 is provided.
Reverting libav's version
Just to test what's going on, I've made a recipe which fetches version 0.8.17 of libav (which uses version 53). When using this instead of 9.18, I have the exact opposite problem, that smart expects but can't find version 54.
Questions
How does smart determine the version number for these shared object files?
What about the do_rootfs() task causes the build to fail at this specific time?
Is there a simple resolution to my specific problem?

1) It's not smart, but rather rpmbuild, that is adding dependencies derived from the ELF DT_NEEDED field (see elfutils -a).
2) The do_rootfs() task is failing because of unresolved dependencies.
3) Since you are using Poky/Yocto and rpm5, there is a simple way to mask the issue (substituting whatever dependencies are causing you heartburn)
echo "unresoved_dependency" > /etc/rpm/sysinfo/Providename
That is just a band-aid; you still need to figure out the packaging issues rather than masking the underlying problem with how you are building rpm packages.

For anyone that still encounter this error: as stated in the README file of the meta-oracle-java repo
There are some known install problems for JRE packages due to dependencies reported by RPM package manager.
Switching to DEB or IPK packaging temporarily fixes this.
ie:
PACKAGE_CLASSES = "package_deb"
or
PACKAGE_CLASSES = "package_ipk"
in your 'local.conf' file

JRuby 9.0.5.0 cannot load compiled ruby files

Our application is a RoR app, and currently uses JRuby version 1.7.22, and JRE 8_65. Our app is an on-prem solution, so we use JRuby to host our application on JVM at the target, Windows Server 2012 R2 system. We compile our ruby code, using
jruby -S jrubyc
This takes the .rb file and compiles it to a .class file. In the original .rb, it loads in the class file, like so.
load __FILE__.sub(/\.rb$/, ".class")
This all works with JRuby 1.7.22
Now, we want to update JRuby to 9.0.5.0, but are experiencing some problems when it comes to deploying our application. Basically, that line of code above inside of the .rb file is not working anymore, and we get the error when trying to run a rake db:setup
rake aborted!
LoadError: C:/appname/app/models/app_attribute.class is not compiled Ruby; use java_import to load normal classes
C:/appname/app/models/app_attribute.rb:1:in `<top>'
C:/appname/db/seeds.rb:10:in `<top>'
C:/appname/db/seeds.rb:9:in `block in (root)'
Tasks: TOP => db:setup => db:seed
(See full trace by running task with --trace)
Great. So I replace load with java_import
rake aborted!
ArgumentError: not a valid Java identifier: C:/appname/app/models/app_attribute.class
uri:classloader:/jruby/java/core_ext/object.rb:43:in `block in java_import'
uri:classloader:/jruby/java/core_ext/object.rb:34:in `java_import'
C:/appname/app/models/app_attribute.rb:1:in `<top>'
C:/appname/db/seeds.rb:10:in `<top>'
C:/appname/db/seeds.rb:9:in `block in (root)'
Tasks: TOP => db:setup => db:seed
(See full trace by running task with --trace)
Still not working, no matter what I try. I looked at this post: https://github.com/jruby/jruby/issues/3018
I tried to pass the parameter
jruby -Xaot.loadClasses=true
But I get a warning saying that aot.LoadClasses is not recognized. EVEN THOUGH I see it in the properties when I type
jruby -Xproperties
I have done A LOT of research on this, and have probably have looked at everything on the internet regarding this. Any input will be greatly appreciated. Is there something I missing? I am not fully adept in Java.
Thank you.

might be the same issue as https://github.com/jruby/jruby/issues/3651
which means you'll need to wait for 9.1 or use a snapshot http://ci.jruby.org/
since, the error is slightly different you should look into reproducing with snapshot and if it fails (might be Windows related) a step-by-step reproduction might speed-up getting the issue resolved.
jruby -Xaot.loadClasses=true
this is not needed with Warbler
But I get a warning saying that aot.LoadClasses is not recognized. EVEN THOUGH I see it in the properties when I type
hmm, could you reproduce this with an empty script and no JRUBY_OPTS ?
I have done A LOT of research on this, and have probably have looked at everything on the internet regarding this. Any input will be greatly appreciated.
you might want to try looking into the issue next time :) or considering getting some support
Is there something I missing? I am not fully adept in Java.
you shouldn't be missing anything - its not a Java issue ...

HypergraphDB Netbeans settings

I want to do something with the HypergraphDB in Java. I'm not very familiar with this language and IDE Netbeans.
I followed steps describing the HGDB installation:Link to tutorial
Now I want to write an example in Java (using NetbeansIDE).
So I created new project, added refferences to the downloaded libraries. OK, now I'm able to import packages with HGDB. The only thing I have in my main method is HyperGraph HG = new HyperGraph(dbLocation);. This code compiles. But get following runtime error:
run:
checkpoint kbytes:0
checkpoint minutes:0
java.lang.IllegalStateException: There is 1 existing transaction opened against the Environment.
Aborting open transactions ...
aborting <Transaction id="28">
at com.sleepycat.je.Environment.close(Environment.java:383)
at org.hypergraphdb.storage.bje.BJEStorageImplementation.shutdown(BJEStorageImplementation.java:178)
at org.hypergraphdb.HGStore.close(HGStore.java:355)
at org.hypergraphdb.HyperGraph.open(HyperGraph.java:392)
at org.hypergraphdb.HyperGraph.open(HyperGraph.java:213)
at org.hypergraphdb.HyperGraph.<init>(HyperGraph.java:200)
at hgdbtest.HgdbTest.main(HgdbTest.java:16)
Exception in thread "main" org.hypergraphdb.HGException: java.lang.NoSuchMethodError: org.hypergraphdb.storage.bje.LinkBinding.objectToEntry(Ljava/lang/Object;Lcom/sleepycat/je/DatabaseEntry;)V
at org.hypergraphdb.HyperGraph.open(HyperGraph.java:395)
at org.hypergraphdb.HyperGraph.open(HyperGraph.java:213)
at org.hypergraphdb.HyperGraph.<init>(HyperGraph.java:200)
at hgdbtest.HgdbTest.main(HgdbTest.java:16)
Caused by: java.lang.NoSuchMethodError: org.hypergraphdb.storage.bje.LinkBinding.objectToEntry(Ljava/lang/Object;Lcom/sleepycat/je/DatabaseEntry;)V
at org.hypergraphdb.storage.bje.BJEStorageImplementation.store(BJEStorageImplementation.java:234)
at org.hypergraphdb.HGStore.store(HGStore.java:119)
at org.hypergraphdb.HGTypeSystem.addPrimitiveTypeToStore(HGTypeSystem.java:185)
at org.hypergraphdb.HGTypeSystem.bootstrap(HGTypeSystem.java:234)
at org.hypergraphdb.HyperGraph.open(HyperGraph.java:355)
... 3 more
Java Result: 1
BUILD SUCCESSFUL (total time: 4 seconds)
I guess it's caused by the native API of the BerkeleyDB.
According to the tutorial, in project options I supply the -Djava.library.path=$HGDB_ROOT/lib/native/$PLATFORM argument on Run card as a VM Option. Instead of the system variables I use full-path to the libraries.
My OS in Windows7. I'm not sure about using slashes or backslashes or double-backslashes as a path-separator.?
So a simply question is: how have I to set up the IDE for using the HypergraphDB?
Thank you for advices!

Judging from the stack trace, you are using the latest version of HyperGraphDB. In that version, the native API is not used. Rather, it's Java only libraries. You have to include the BerkeleyDB Java Edition 5.0.34 jar in your runtime classpath. You can get it either from the Oracle http://www.oracle.com/technetwork/products/berkeleydb/downloads/index.html or from the HyperGraphDB Maven repository: http://hypergraphdb.org/maven/org/hypergraphdb/hgbdbje/1.2/hgbdbje-1.2.jar

I had the same issue. I fixed it (by accident) by fixing the order of the libraries on which you're HyperGraphDB application relies on. The library je-[version].jar has to be ABOVE (and hence to be referenced before) db-[version].jar