running ant JUnitTask

message from ant:


BUILD FAILED
.../build.xml:346: Problem: failed to create task or type junit
Cause: the class org.apache.tools.ant.taskdefs.optional.junit.JUnitTask was not found.
        This looks like one of Ant's optional components.

....

this is due to lack of  ant-junit.jar file.

one method is to download ant-junit.jar from here: http://www.java2s.com/Code/Jar/ABC/Downloadantjunitjar.htm
and copy it under $ANT_HOME/lib

another method is to download a newer version of ant (http://ant.apache.org/)
ant 1.8.2 comes with that jar file..

http://ant.apache.org/manual/Tasks/junit.html explains how to run junit task..