Validate the word size (bitness) of JDK

[rmartin16]

Describe the bug

Building an Android app is not compatible with a 32bit JDK and Gradle outputs a bit of a cryptic error when such a JDK is used with Briefcase.

[helloworld] Building Android APK...
>>> Android emulator is already installed.

>>> Running Command:
>>>     'C:\Users\user\github\beeware\briefcase\tmp\helloworld\build\helloworld\android\gradle\gradlew.bat' --console plain assembleDebug
>>> Working Directory:
>>>     C:\Users\user\github\beeware\briefcase\tmp\helloworld\build\helloworld\android\gradle
>>> Environment Overrides:
>>>     ANDROID_HOME=C:\Users\user\AppData\Local\BeeWare\briefcase\Cache\tools\android_sdk
>>>     ANDROID_SDK_ROOT=C:\Users\user\AppData\Local\BeeWare\briefcase\Cache\tools\android_sdk
>>>     JAVA_HOME=C:\Users\user\Desktop\jdk-17.0.8.1+1 32bit
Starting a Gradle Daemon, 1 incompatible and 1 stopped Daemons could not be reused, use --status for details

FAILURE: Build failed with an exception.

* What went wrong:
Unable to start the daemon process.
This problem might be caused by incorrect configuration of the daemon.
For example, an unrecognized jvm option is used.
Please refer to the User Manual chapter on the daemon at https://docs.gradle.org/8.0/userguide/gradle_daemon.html
Process command line: C:\Users\user\Desktop\jdk-17.0.8.1+1 32bit\bin\java.exe --add-opens=java.base/java.util=ALL-UNNAMED --add-opens=java.base/java.lang=ALL-UNNAMED --add-opens=java.base/java.lang.invoke=ALL-UNNAMED --add-opens=java.prefs/java.util.prefs=ALL-UNNAMED --add-opens=java.base/java.nio.charset=ALL-UNNAMED --add-opens=java.base/java.net=ALL-UNNAMED --add-opens=java.base/java.util.concurrent.atomic=ALL-UNNAMED -Xmx2048m -Dfile.encoding=UTF-8 -Duser.country=US -Duser.language=en -Duser.variant -cp C:\Users\user\.gradle\wrapper\dists\gradle-8.0-all\a2o1xoguejy6msdh0lk99lxza\gradle-8.0\lib\gradle-launcher-8.0.jar org.gradle.launcher.daemon.bootstrap.GradleDaemon 8.0
Please read the following process output to find out more:
-----------------------
Error occurred during initialization of VM
Could not reserve enough space for 2097152KB object heap

Steps to reproduce

1. Download and extract https://github.com/adoptium/temurin17-binaries/releases/download/jdk-17.0.8.1%2B1/OpenJDK17U-testimage_x86-32_windows_hotspot_17.0.8.1_1.zip
2. Set JAVA_HOME to the extracted directory
3. Run briefcase build android

Expected behavior

Briefcase enforces that the bitness of the JDK must match the bitness of the OS.

Of note, I learned in #1360 that bitness checks are deceptively difficult in the general case....so, beware...

Determining the bitness of the JDK may also be non-trivial given users can use any ole JDK. The java -XshowSettings:properties -version command includes with but it isn't entirely clear if arbitrary builds of JDK include the same information....and format it consistently...

64bit `java -XshowSettings:properties -version` output

❯ java -XshowSettings:properties
Property settings:
    file.encoding = UTF-8
    file.separator = /
    java.class.path = 
    java.class.version = 61.0
    java.home = /usr/lib/jvm/java-17-amazon-corretto
    java.io.tmpdir = /tmp
    java.library.path = /usr/java/packages/lib
        /usr/lib64
        /lib64
        /lib
        /usr/lib
    java.runtime.name = OpenJDK Runtime Environment
    java.runtime.version = 17.0.7+7-LTS
    java.specification.name = Java Platform API Specification
    java.specification.vendor = Oracle Corporation
    java.specification.version = 17
    java.vendor = Amazon.com Inc.
    java.vendor.url = https://aws.amazon.com/corretto/
    java.vendor.url.bug = https://github.com/corretto/corretto-17/issues/
    java.vendor.version = Corretto-17.0.7.7.1
    java.version = 17.0.7
    java.version.date = 2023-04-18
    java.vm.compressedOopsMode = Zero based
    java.vm.info = mixed mode, sharing
    java.vm.name = OpenJDK 64-Bit Server VM
    java.vm.specification.name = Java Virtual Machine Specification
    java.vm.specification.vendor = Oracle Corporation
    java.vm.specification.version = 17
    java.vm.vendor = Amazon.com Inc.
    java.vm.version = 17.0.7+7-LTS
    jdk.debug = release
    line.separator = \n 
    native.encoding = UTF-8
    os.arch = amd64
    os.name = Linux
    os.version = 6.4.6-76060406-generic
    path.separator = :
    sun.arch.data.model = 64
    sun.boot.library.path = /usr/lib/jvm/java-17-amazon-corretto/lib
    sun.cpu.endian = little
    sun.io.unicode.encoding = UnicodeLittle
    sun.java.launcher = SUN_STANDARD
    sun.jnu.encoding = UTF-8
    sun.management.compiler = HotSpot 64-Bit Tiered Compilers
    sun.stderr.encoding = UTF-8
    sun.stdout.encoding = UTF-8
    user.country = US
    user.dir = /home/russell
    user.home = /home/russell
    user.language = en
    user.name = russell

openjdk version "17.0.7" 2023-04-18 LTS
OpenJDK Runtime Environment Corretto-17.0.7.7.1 (build 17.0.7+7-LTS)
OpenJDK 64-Bit Server VM Corretto-17.0.7.7.1 (build 17.0.7+7-LTS, mixed mode, sharing)

32bit `java -XshowSettings:properties -version` output

❯ ~/zulu17.44.53-ca-fx-jdk17.0.8.1-linux_i686/bin/java -XshowSettings:properties -version
Property settings:
    file.encoding = UTF-8
    file.separator = /
    java.class.path = 
    java.class.version = 61.0
    java.home = /home/russell/zulu17.44.53-ca-fx-jdk17.0.8.1-linux_i686
    java.io.tmpdir = /tmp
    java.library.path = /usr/java/packages/lib
        /lib
        /usr/lib
    java.runtime.name = OpenJDK Runtime Environment
    java.runtime.version = 17.0.8.1+1-LTS
    java.specification.name = Java Platform API Specification
    java.specification.vendor = Oracle Corporation
    java.specification.version = 17
    java.vendor = Azul Systems, Inc.
    java.vendor.url = http://www.azul.com/
    java.vendor.url.bug = http://www.azul.com/support/
    java.vendor.version = Zulu17.44+53-CA
    java.version = 17.0.8.1
    java.version.date = 2023-08-24
    java.vm.info = mixed mode, sharing
    java.vm.name = OpenJDK Server VM
    java.vm.specification.name = Java Virtual Machine Specification
    java.vm.specification.vendor = Oracle Corporation
    java.vm.specification.version = 17
    java.vm.vendor = Azul Systems, Inc.
    java.vm.version = 17.0.8.1+1-LTS
    jdk.debug = release
    line.separator = \n 
    native.encoding = UTF-8
    os.arch = i386
    os.name = Linux
    os.version = 6.4.6-76060406-generic
    path.separator = :
    sun.arch.data.model = 32
    sun.boot.library.path = /home/russell/zulu17.44.53-ca-fx-jdk17.0.8.1-linux_i686/lib
    sun.cpu.endian = little
    sun.io.unicode.encoding = UnicodeLittle
    sun.java.launcher = SUN_STANDARD
    sun.jnu.encoding = UTF-8
    sun.management.compiler = HotSpot Tiered Compilers
    sun.stderr.encoding = UTF-8
    sun.stdout.encoding = UTF-8
    user.country = US
    user.dir = /home/russell
    user.home = /home/russell
    user.language = en
    user.name = russell

openjdk version "17.0.8.1" 2023-08-24 LTS
OpenJDK Runtime Environment Zulu17.44+53-CA (build 17.0.8.1+1-LTS)
OpenJDK Server VM Zulu17.44+53-CA (build 17.0.8.1+1-LTS, mixed mode, sharing)

Screenshots

No response

Environment

• Operating System: Windows 11
• Python version: 3.11.3
• Software versions:
  • Briefcase: 0.3.16.dev225+g44f1045a.d20230923

Logs

Windows build log with 32bit JDK
briefcase.2023_09_23-11_43_47.build.log

Additional context

Of note, I was able to use a 32bit JDK on Linux....although, there's probably no need to allow this.

Linux build log with 32bit JDK
briefcase.2023_09_23-11_54_16.build.log

[mhsmith]

Could not reserve enough space for 2097152KB object heap

This will be because of the -Xmx setting in gradle.properties. The current version of that file in the template is identical to the one generated by the Android Studio new project wizard, and I think they probably increased it to 2048 MB around the same time that Android Studio stopped supporting 32-bit build machines.

[rmartin16]

Could not reserve enough space for 2097152KB object heap

This will be because of the -Xmx setting in gradle.properties. The current version of that file in the template is identical to the one generated by the Android Studio new project wizard, and I think they probably increased it to 2048 MB around the same time that Android Studio stopped supporting 32-bit build machines.

Right. Are you suggesting, though, that we shouldn't enforce such a bitness check?

FWIW, when I change this to 1024m, the build succeeds on Windows for a 32bit JDK.

[mhsmith]

Reducing the limit would be a bad idea becuase all testing of both the Android and Chaquopy Gradle plugins will be done at the default limit. So I agree the bitness check is the way to go.

[rmartin16]

Reducing the limit would be a bad idea becuase all testing of both the Android and Chaquopy Gradle plugins will be done at the default limit. So I agree the bitness check is the way to go.

All right; that definitely makes sense. Given a 32bit JDK is technically feasible, it might be reasonable then to just implement a warning for the user instead of a hard stop error.