antlr3-gradle-java21-example

An example ANTLR3 project, using Gradle (Kotlin DSL) and Java 21 for modern developer experience.

Meta-Information

• Project name: antlr3-gradle-java21-example.

• Source package: org.javabujin.example.

• Gradle version: 8.10.2.

• Java version: 21.

• ANTLR version: 3.5.3.

• StringTemplate version: 3.2.1.

• The base project was generated using VSCode and the Gradle extension vscjava.vscode-gradle, version 3.16.2024102102.

Useful Commands

General Gradle Commands

• ./gradlew clean - Clean the project.
• ./gradlew build - Build the project.
• ./gradlew run - Run the project.
• ./gradlew test - Run the tests.

ANTLR Commands

• ./gradlew generateGrammarSource - Generate the ANTLR sources.
• ./gradlew generateTestGrammarSource - Generate the ANTLR test sources.
• ./gradlew generateSourceSetGrammarSource - Generate the ANTLR source set sources.

The example language

• The example language is a simple "calculator" language (based on the Arithmetic Expression example from The Definitive ANTLR 3 Reference).

Notes

• ANTLR 3 grammars are placed in the app/src/main/antlr directory.

• New rules for building and using ANTLR 3 was added to the app/build.gradle.kts file.

  • The generated sources in the build directory is copied to the app/src/main/java/${mainAntlrGeneratedSourcesPath} directory.
  • Then, the original generated sources are deleted from the build directory.
  • An additional clean up rule is added to the clean task to remove the generated sources from the app/src/main/java/${mainAntlrGeneratedSourcesPath} directory (remove the whole directory).

• StringTemplate was added to the project dependencies as using it with Java 21 somehow causes trouble (i.e. the language server recognizes experimental StringTemplate of Java 21 instead of the ANTLR3 version).

  • If you are not using StringTemplate, you can remove it from the dependencies.
  • Otherwise, you can try adding import org.antlr.stringtemplate.StringTemplate; to the header of your generated parsers (using @header).