Current main `JniEnv`

Property definitions

	# Current main `JniEnv`
	fun jni_env: JniEnv
	do
		if jni_env_cache == null then create_default_jvm
		return jni_env_cache.as(not null)
	end

lib/java/ffi_support.nit:45,2--50,4

	redef fun jni_env do return jvm.attach_current_thread

lib/android/dalvik.nit:40,2--54