Linux-on-Android

How to set up a Java development environment on an Android phone

Revised installation

• Install CodeBoard (on-screen keyboard)
• Install UserLAnd from Play Store
• Launch UserLAnd and open Arch Linux (graphical interface)
• Set random placement option of TWM:
  • cp /usr/share/X11/twm/system.twmrc .twmrc
  • nano .twmrc
  • Move insertion point down to the blank line following the first set of options
  • Add line: RandomPlacement
  • Type <ctrl-x>y<enter> to save changes and exit
  • NOTE: This change eliminates the step of "placing" applications at launch
• Update package registry:
  • sudo pacman -Syu
• Install developer tools:
  • sudo pacman -S base-devel glibc
• Install man:
  • sudo pacman -S man
• Install git:
  • sudo pacman -S git
  • git config --global user.email "john.smith@email.com"
  • git config --global user.name "John Smith"
  • git config --global credential.helper store
  • git config --global fetch.prune true
  • Perform a "push" to GitHub, entering username and PAT (personal access token)
• Install archive utilities:
  • sudo pacman -S zip unzip xarchiver
• Install yay package manager:
  • NOTE: This package must be built locally, because no one appears to have published it for the aarch64 architecture.
  • https://github.com/Jguer/yay#source
• Install Visual Studio Code via yay:
  • yay -S visual-studio-code-bin
  • Create code-flags.conf file:
    • nano .config/code-flags.conf
    • Add line: --no-sandbox
    • Add line: --user-data-dir=/home/userland/.vscode-data
    • Type <ctrl-x>y<enter> to save changes and exit
    • NOTE: This is needed because UserLAnd doesn't maintain correct ownership/permissions of file:
      /opt/visual-studio-code/chrome-sandbox
• Set editor, difftool and mergetool for git:
  • git config --global core.editor nano
  • git config --global -e

[core]
  editor = code --wait
[diff]
  tool = vscode
[difftool "vscode"]
  cmd = code --wait --diff $LOCAL $REMOTE
[merge]
  tool = vscode
[mergetool "vscode"]
  cmd = code --wait $MERGED

• Install SdkMan:

  • curl -s "https://get.sdkman.io" | bash

• Install Maven:

  • sudo pacman -S maven

• Install Gradle:

  • sdk install gradle

• Install/create Maven/Gradle/GitHub artifacts:

  • ~/.m2
    • settings.xml
  • ~/.gnupg
    • secring.gpg
    • pubring.gpg
  • ~/.gradle/
    • gradle.properties

• JDK11, JDK8:

  • sudo pacman -S jdk11-openjdk
  • sudo pacman -S jdk8-openjdk

• Add exports for JDK8_HOME and JDK11_HOME to .bashrc:

  • ~/.bashrc

    export JDK8_HOME=/urs/lib/jvm/java-8-openjdk
    export JDK11_HOME=/urs/lib/jvm/java-11-openjdk
  

• Create Maven toolchains configuration:

  • ~/.m2/toolchains.xml

    <?xml version="1.0" encoding="UTF8"?>
    <toolchains>
      <!-- JDK toolchains -->
      <toolchain>
        <type>jdk</type>
        <provides>
          <version>8</version>
        </provides>
        <configuration>
          <jdkHome>/usr/lib/jvm/java-8-openjdk</jdkHome>
        </configuration>
      </toolchain>
      <toolchain>
        <type>jdk</type>
        <provides>
          <version>11</version>
        </provides>
        <configuration>
          <jdkHome>/usr/lib/jvm/java-11-openjdk</jdkHome>
        </configuration>
      </toolchain>
    </toolchains>
  

• Install wget:

  • sudo pacman -S wget

• Install Bazelisk:

  • wget https://github.com/bazelbuild/bazelisk/releases/download/v1.17.0/bazelisk-linux-arm64
  • mv bazelisk-linux-arm64 bazelisk
  • chmod +x bazelisk
  • mv bazelisk /usr/sbin/bazelisk

• Install buildifier:

  • wget https://github.com/bazelbuild/buildtools/releases/download/v6.1.2/buildifier-linux-arm64
  • mv buildifier-linux-arm64 buildifier
  • chmod +x buildifier
  • mv buildifier /usr/sbin/buildifier

• Install jed editor:

  • NOTE: This package must be built locally, because no one appears to have published it for the aarch64 architecture.
  • sudo pacman -S slang libxt
  • git clone https://github.com/jedsoft/jed.git
  • cd jed
  • ./configure --prefix=/usr/local
  • make clean
  • make
  • make xjed
  • make install

• Install Firefox and its driver:

  • sudo pacman -S firefox geckodriver

• Disable Firefox sandboxing in .bashrc:

  • ~/.bashrc

    export MOZ_FAKE_NO_SANDBOX=1
  

• Open Firefox

  • dbus-run-session -- firefox

• Clone the Selenium Foundation repository:

  • git clone https://github.com/sbabcoc/Selenium-Foundation.git

Hardware/Accessories

• LG Velvet (LM-G900TM)
  • Android 11
  • MediaTek Dimensity 1000C MT6883 2,00 GHz [Number of cores: 8]
  • Internal memory: 128 GB
  • RAM memory: 6 GB
  • 1080 x 2460
• Pixio PX160 Portable Monitor
  • 1920 x 1080
• Folding Bluethooth keyboard/trackpad
• Zippered hard-sided case for keyboard, cables, and power supply

Stuff you probably won't need

LLVM and CLang

• sudo pacman -S llvm
• pacman -S llvm-libs
• pacman -S clang
• pacman -S python-pip
• pacman -S cbindgen
• pacman -S nodejs npm

To install JDK7 with SunEC support:

• pacman -S jdk7-openjdk
• Install SubEC components from Linux-on-Android repository into JDK7

To build the SunEC JAR:

• Install Mercurial (version control client):
  • sudo -u scoba yay -S mercurial
• ... with which I downloaded the source for OpenJDK 7
• ... so that I could build a JAR from the SunEC source files
• ... which I dropped into the jre/lib/ext folder of java-7-openjdk
• I duplicated the 'libsunec.so' native library from JDK8 to JDK7, which hasn't blown up yet.

NOTE: The ability to drop an unsigned encryption library into the JRE without complaint was more than a bit surprising. Although this required file-system access, this seems like a bit of a security vulnerability to me.

To clone the geckodriver repo, you need the 'git-cinnabar' extension:

• Clone and build git-cinnabar extension:
  • git clone https://github.com/glandium/git-cinnabar.git
  • cd git-cinnabar
  • make
  • Add git-cinnabar folder to the PATH