see this test https://github.com/wsw0108/node-java/commit/c83294c7ab961fc664e9dbf6a3a01ce98dfdfdec#diff-35c8e2e9c6da3123916ca12c589ff5c7L52 'char' from java are unicoded. http://docs.oracle.com/javase/7/docs/technotes/guides/jni/spec/types.html