FAQ

1.Q: How do I fix OutOfMemory while building DDF ?

A: DDF uses maven to build project, you can set MAVEN memory to higher values, for example: export MAVEN_OPTS=-XX:MaxPermSize=128m

2.Q: How to fix ClassNotFound exception while using R-DDF ?

A: R-DDF use rJava to invoke DDF Java class, make sure you're using Java 1.7, R 3.x and you have installed rJava. This error happens mostly on MacOS X.

• First you need to set JAVA PATH properly, in Mac it looks something like this

JAVA_LD_LIBRARY_PATH=/Library/Java/JavaVirtualMachines/jdk1.7.0_67.jdk/Contents/Home/jre/lib/server
JAVA_LIBS='-L/Library/Java/JavaVirtualMachines/jdk1.7.0_67.jdk/Contents/Home/jre/lib/server -ljvm' 
JAVA_CPPFLAGS='-I/Library/Java/JavaVirtualMachines/jdk1.7.0_67.jdk/Contents/Home/include -I/Library/Java/JavaVirtualMachines/jdk1.7.0_67.jdk/Contents/Home/include/darwin'

• Secondly sh R CMD javareconf -e
• Then export

DYLD_LIBRARY_PATH=/Library/Java/JavaVirtualMachines/jdk1.7.0_67.jdk/Contents/Home/jre/lib/server/

3.Q: I have this error while running R CMD javareconf -e make: llvm-gcc-4.2: No such file or directory

A: This error occurs mostly on MacOSX. It happens because you can't install rJava. Please follow this instruction

4.Q: I don't have Java on my machine, how to install Java 7 on Mac ?

A: Apple and Oracle do not support Java 1.7 out of the box, you need to install manually

5.Q: I have this error JAVA_HOME is not set properly, how to fix that ?

A: You need to set JAVA_HOME properly, for example: export JAVA_HOME=/usr/libexec/java_home

6.Q: I saw this error message "You must build DDF's Java core and spark package firstly" A: You need to run bin/run-once.sh successfully.

7.Q: How can I install rJava ? A: in R, run R install.packages("rJava")

8.Q: I have this error while installing rJava "unable to load shared object '/Library/Frameworks/R.framework/Resources/modules//R_X11.so'" A: