build.xml

<project name="MyProject" default="all" basedir=".">
	<dirname property="basedir" file="${ant.file}"/>

	<!-- Global Libraries -->

	<path id="library.antlr-4.2-complete">
		<pathelement location="/usr/local/lib/antlr-4.2-complete.jar"/>
	</path>

	<path id="library.st-4.0.7">
		<pathelement location="/usr/local/lib/ST-4.0.7.jar"/>
	</path>

	<!-- set global properties for this build -->
	<property name="srcroot" location="${basedir}/src"/>
	<property name="src" location="${basedir}/src/java"/>
	<property name="grammars" location="${basedir}/src/grammar"/>
	<property name="gen" location="${basedir}/src/gen"/>
	<property name="build" location="${basedir}/out/production/tool"/> <!-- mimic what intellij uses -->

	<path id="classpath">
		<path refid="library.antlr-4.2-complete"/>
		<path refid="library.st-4.0.7"/>
	</path>

	<target name="init">
		<!-- Create the build directory structure used by compile -->
		<mkdir dir="${build}"/>
	</target>

	<target name="antlr4-init">
		<!-- ANTLR generates X.java or XParser.java or XLexer.java from X.g4
		     so we use a touch file to indicate when we've just build all
		     grammars.  File is wiped out during clean target.
		-->
		<property name="antlr4.touch" value="${build}/antlr4.touch" />
	</target>


	<macrodef name="antlr4">
		<attribute name="file"/>
		<attribute name="dest"/>
		<element name="args" optional="true"/>

		<sequential>
			<echo message="Run antlr 4 on @{file}"/>
			<local name="package"/>
			<local name="path.antlr4.local"/>
			<local name="sources.antlr4.local"/>

			<property name="package" value="mantra"/>
			<java classname="org.antlr.v4.Tool" fork="true" failonerror="true">
				<arg value="-o"/>
				<arg value="${gen}/${package}"/>
				<arg value="-package"/>
				<arg value="${package}"/>
				<args/>
				<arg line="@{file}"/>
				<classpath>
					<path refid="classpath"/>
					<pathelement location="${java.class.path}"/>
				</classpath>
			</java>
		</sequential>
	</macrodef>

	<target name="chk-parsers-up-to-date" depends="antlr4-init">
		<!-- if any .g4 or .tokens file is newer than the touch file (i.e.,
		     last time we built the parsers, indicate we need a rebuild
		-->
		<uptodate property="parsers-up-to-date" targetfile="${antlr4.touch}" >
			<srcfiles dir="${grammars}">
				<include name="**/*.g4"/>
				<include name="**/*.tokens"/> <!-- we might create a .tokens file by hand -->
			</srcfiles>
		</uptodate>
	</target>

	<!-- how to run antlr4 on a dir of grammars -->
	<target name="antlr4" depends="init, chk-parsers-up-to-date" unless="parsers-up-to-date">
		<echo message="Generating Parsers for ANTLR 4 grammars"/>
		<antlr4 file="${grammars}/mantra/Mantra.g4" dest="${build}">
			<args>
				<arg value="-listener"/>
			</args>
		</antlr4>
		<touch file="${antlr4.touch}" mkdirs="true"/>
	</target>

	<target name="compile" depends="init, antlr4" description="Compile module tool; production classes">
		<javac destdir="${build}" includeantruntime="false" debug="true">
			<classpath refid="classpath"/>
			<src path="${src}"/>
			<src path="${gen}"/>
		</javac>

	    <copy todir="${build}"> <!-- copy any non-java resource files to build dir -->
	      <fileset dir="${basedir}/resources">
	        <exclude name="**/?*.java"/>
	        <type type="file"/>
	      </fileset>
	    </copy>
	  </target>

	<target name="clean" description="clean up" >
		<delete dir="${build}"/>
		<delete dir="${gen}"/>
	</target>

	<target name="all" depends="init, antlr4, compile" description="do everything" >

	</target>

</project>