This week's book giveaway is in the OCAJP 8 forum. We're giving away four copies of OCA Java SE 8 Programmer I Study Guide and have Edward Finegan & Robert Liguori on-line! See this thread for details.
It would appear that you have errors in your source code, but those errors are not being displayed. Try not forking the java compiler (let the JVM running the Ant build script do the compiling), that should result in the errors being listed.