Antlr4 Gradle Plugin

The antlr4-gradle-plugin provides an easy way to generate grammars with Antlr4 using Gradle.

Installation

Use the following snippet inside a Gradle build file:

build.gradle

buildscript {
    repositories {
        maven {
            name 'JFrog OSS snapshot repo'
            url  'https://oss.jfrog.org/oss-snapshot-local/'
        }
        jcenter()
    }

    dependencies {
        classpath 'me.champeau.gradle:antlr4-gradle-plugin:0.1'
    }
}

repositories {
   jcenter()
}

apply plugin: 'me.champeau.gradle.antlr4'

Configuration

The plugin adds a new task named antlr4. This task exposes 5 properties as part of its configuration

source	where the source grammars are. Type: File. Default: src/main/antlr4.
output	where generated sources go. Type: File. Default: $buildDir/generated-src.
listener	generate parse tree listener. Type: boolean. Default: true
visitor	generate parse tree visitor. Type: boolean. Default: true
extraArgs	extra arguments to pass to the antlr4 tool. Type: List. Default: empty. Example: extraArgs=['-Werror']

Usage

Basic generation

Generating grammars can be done by calling the antlr4 task:

gradle antlr4

Dependency on generated sources

In general, you will want your main project to depend on the generated sources for compilation. You can easily do this by adding this configuration into your build.gradle:

build.gradle

// make the Java compile task depend on the antlr4 task
compileJava.dependsOn antlr4

// add the generated source files to the list of java sources
sourceSets.main.java.srcDirs += antlr4.output

// add antlr4 to classpath
configurations {
   compile.extendsFrom antlr4
}