build.xml

<project name="WindowSelector">
  <property name="src.dir" value="src"/>
  <property name="tests.dir" value="tests"/>
  <property name="build.dir" value="build"/>
  <property name="classes.dir" value="${build.dir}/classes"/>
  <property name="jar.dir" value="${build.dir}/jar"/>
  <property name="doc.dir" value="${build.dir}/doc"/>
  <property name="lib.dir" value="lib"/>
  
  <property name="main.class" value="TestMain"/>
  
  <property name="junit.path" value="${lib.dir}/junit-4.12.jar"/>
  <property name="hamcrest.path" value="${lib.dir}/hamcrest-core-1.3.jar"/>
  <property name="class.path" value="${junit.path}:${hamcrest.path}"/>
  
  <target name="clean">
    <delete dir="${build.dir}"/>
  </target>
  <target name="build">
    <mkdir dir="${classes.dir}"/>
    <javac srcdir="${src.dir}" destdir="${classes.dir}" includeantruntime="false" encoding="utf8" classpath="${class.path}" debug="on"/>
  </target>
  <target name="jar" depends="build">
    <mkdir dir="${jar.dir}"/>
    <jar destfile="${jar.dir}/${ant.project.name}.jar" basedir="${classes.dir}">
      <manifest>
        <attribute name="Main-Class" value="${main.class}"/>
      </manifest>
    </jar>
  </target>
  <target name="run" depends="build">
    <java classname="${main.class}" classpath="${classes.dir}" fork="true"/>
  </target>
  <target name="javadoc">
    <mkdir dir="${doc.dir}"/>
    <javadoc destdir="${doc.dir}" sourcepath="${src.dir}" classpath="${class.path}" charset="UTF-8" link="https://docs.oracle.com/javase/8/docs/api/"/>
  </target>
  <target name="test" depends="build">
    <junit fork="true" printsummary="yes" showoutput="yes">
      <formatter type="plain" usefile="false"/>
      <classpath>
        <pathelement path="${junit.path}"/>
        <pathelement path="${hamcrest.path}"/>
        <pathelement location="${classes.dir}"/>
      </classpath>
      <batchtest>
        <fileset dir="${classes.dir}" includes="${tests.dir}/*.class"/>
      </batchtest>
    </junit>
  </target>
</project>