Example Xcode project using J2OBJC and RealmSwift (not working - see realm/realm-swift#4286)
Download J2OBJC to any folder you like:
J2OBJC_ROOT=~/j2objcDist
mkdir -p $J2OBJC_ROOT; pushd $J2OBJC_ROOT
curl -L https://github.com/google/j2objc/releases/download/1.2/j2objc-1.2.zip > j2objc-1.2.zip
unzip j2objc-1.2.zip; popd
Now, set the User-Defined Setting "J2OBJC_HOME" to the used folder.
After setting up, you should be good to go. Run the provided test "testSubmoduleLib17".