@Override
    public boolean isBundleGemfileDefined() throws JRubyInvalidRuntimeException {
        return getInitialized().isBundleGemfileDefined();
    }
Indirects onto JRuby with initializing ScriptingContainer lazily.
embulk-core/src/main/java/org/embulk/jruby/LazyScriptingContainerDelegate.java