Bach.java - Java Shell Builder

Use Java source (in jshell) to build your modular Java project.

    ___      ___      ___      ___
   /\  \    /\  \    /\  \    /\__\
  /::\  \  /::\  \  /::\  \  /:/__/_
 /::\:\__\/::\:\__\/:/\:\__\/::\/\__\
 \:\::/  /\/\::/  /\:\ \/__/\/\::/  /
  \::/  /   /:/  /  \:\__\    /:/  /
   \/__/    \/__/    \/__/    \/__/.java

No need to be a maven to be able to use a build tool - forax/pro

Fast-forward to install-jdk.sh section.

Execute Bach.java on-the-fly

This section will help you get started with Bach.jsh used as a remote load-file of jshell.

0. Install JDK 11 or later

Make sure you have JDK 11 or later installed and configured. jshell should be executable from any directory and print its version via:

<path/> jshell --version
jshell 11.0.2

1. Source Bach.jsh into JShell

Open a command shell and change into the directory containing your modular Java project.

<path/> jshell https://bit.ly/bach-jsh

That's all you need to build a modular Java project.

Note: the shortened https://bit.ly/bach-jsh expands to https://raw.githubusercontent.com/sormuras/bach/master/src/bach/Bach.jsh

For immediate results, such as fail-fast on errors, use:

jshell --execution=local https://bit.ly/bach-jsh

For more information what Bach.java is doing at runtime, use:

jshell --execution=local -J-Debug=true https://bit.ly/bach-jsh

For more details consult the output of jshell --help.

Bootstrap Bach.java

This section will help you get started with Bach.java used as single file source code Java program.

0. Install JDK 11 or later

Make sure you have JDK 11 or later installed and configured. jshell should be executable from any directory and print its version via:

<path/> jshell --version
jshell 11.0.2

1. Create demo directory

Create an empty directory and change into it. On Windows, you may open a command prompt and enter mkdir demo & cd demo. On Linux and Mac OS, it could read mkdir demo && cd demo.

<path/demo/> | // blinking cursor

2. Download Bach.java

Either download a copy of Bach.java from GitHub manually or let jshell do it for you:

<path/demo/> jshell https://bit.ly/boot-bach

Note: the shortened https://bit.ly/boot-bach expands to https://raw.githubusercontent.com/sormuras/bach/master/boot.jsh

<path/demo/>
.
├── bach                 // Linux/Mac OS launch script | 
├── bach.bat             // Windows batch file         |    Just convenient short-cuts for:
└── .bach                //                             \__   java .bach/master/Bach.java  
    └── master           //
        └── Bach.java    // Java Shell Builder

3. Scaffold, build and launch demo project

Remember to prepend ./ before each bach command when running on Linux or Mac OS.

<path/demo/> bach scaffold
<path/demo/> bach build
<path/demo/> bach launch

Available Actions

java Bach.java help prints

Usage of Bach.java (master):  java Bach.java [<action>...]

Available default actions are:
 build        Build modular Java project in base directory.
 clean        Delete all generated assets - but keep caches intact.
 erase        Delete all generated assets - and also delete caches.
 help         Print this help screen on standard out... F1, F1, F1!
 launch       Start project's main program.
 tool         Run named tool consuming all remaining arguments:
                tool <name> <args...>
                tool java --show-version Program.java
 scaffold     Create modular Java sample project in base directory.

Directory Layout

Project with one more more modules.

demo
  + src
    + com.greetings
    + org.astro
    + ...

Project with one more more modules and test modules.

demo
  + src
    + com.greetings
    + org.astro
    + ...
  + test
    + com.greetings
    + org.astro
    + ...
    + integration
    + ...

install-jdk.sh

install-jdk.sh main purpose is to install the latest-and-greatest available OpenJDK release from jdk.java.net. It supports GA releases and builds provided by Oracle as well.

Options of install-jdk.sh

-h|--help                 Displays this help
-d|--dry-run              Activates dry-run mode
-s|--silent               Displays no output
-e|--emit-java-home       Print value of "JAVA_HOME" to stdout (ignores silent mode)
-v|--verbose              Displays verbose output

-f|--feature 9|10|...|ea  JDK feature release number, defaults to "ea"
-l|--license GPL|BCL      License defaults to "GPL"
-o|--os linux-x64|osx-x64 Operating system identifier (works best with GPL license)
-u|--url "https://..."    Use custom JDK archive (provided as .tar.gz file)
-w|--workspace PATH       Working directory defaults to user's ${HOME}
-t|--target PATH          Target directory, defaults to first component of the tarball
-c|--cacerts              Link system CA certificates (currently only Debian/Ubuntu is supported)

How to set JAVA_HOME with install-jdk.sh

• Source install-jdk.sh into current shell to install latest OpenJDK and let it update JAVA_HOME and PATH environment variables:

  • source ./install-jdk.sh Caveat: if an error happens during script execution the calling shell will terminate

• Provide target directory path to use as JAVA_HOME:

  • JAVA_HOME=~/jdk && ./install-jdk.sh --target $JAVA_HOME && PATH=$JAVA_HOME/bin:$PATH

• Run install-jdk.sh in a sub-shell to install latest OpenJDK and emit the installation path to stdout:

  • JAVA_HOME=$(./install-jdk.sh --silent --emit-java-home)
  • JAVA_HOME=$(./install-jdk.sh --emit-java-home | tail --lines 1)

be free - have fun