Building Ion Fusion

Prerequisites:

• Install a Java runtime, version 17 or later. We recommend Amazon Corretto.
  • This project builds for Java 8, but its Gradle tooling requires 17.
• Install Git.
• Ensure that java and git are on your shell's PATH.

Building from source should be straightforward:

git clone https://github.com/ion-fusion/fusion-java.git
cd fusion-java
./gradlew build

After a successful build, you'll have a basic SDK under sdk/build/install/ion-fusion-sdk. The notable artifacts within that directory are:

• bin/fusion is the fusion CLI
• docs/fusion.html is the documentation for the Ion Fusion language
• docs/javadoc/index.html is the documentation embedding Ion Fusion in your Java application
• lib holds the jars needed for embedding

To experiment with the CLI, add the bin to your path:

PATH=$PATH:$PWD/sdk/build/install/ion-fusion-sdk/bin
fusion help

That should give you an overview of the CLI's subcommands.

About JAVA_HOME

In general, we recommend that you avoid setting JAVA_HOME in your shell while working with this project (or, frankly, any time). Since different projects have different JDK requirements, it's quite likely that any setting will be wrong somewhere.

This project compiles with and runs on a relatively old JDK version, while requiring a relatively new JDK version for its Gradle build tooling. Gradle's startup process will use the JDK from JAVA_HOME if that is set, otherwise the java command on your PATH. We recommend that the java on PATH be as new as possible.

In some contexts, JAVA_HOME and/or the java on PATH might be injected by your tools. For example, recent releases of IntelliJ IDEs will do this by default for its built-in terminal, setting JAVA_HOME to the project's runtime JDK, not the one required to build. You should disable this in Settings | Tools | Terminal | Add project JDK to PATH to avoid interference.

What's Next?

With the fusion CLI ready to go, you can follow the CLI tutorial and run some code!