Ant Build OutOfMemory issue

If 'javac' task is used with fork option then , javac will run in his own process and memory should be directly assigned to the javac using 'memoryinitialsize' and 'memorymaximumsize':

javac   srcdir="${src}"
            destdir="${classes}"
            source="1.6"
            debug="true"
            fork="true"
            deprecation="off"
            memoryinitialsize="512m"
            memorymaximumsize="1024m"