code: def java_home():
      """
      Get jdk directory path
      """
      from . import runtime_java
  
      jdk_dir = runtime_java.get_build_java_dir(binary_path("jdk"))
      if not jdk_dir:
          raise Exception(
              "Cannot find jdk - make sure 'jdk' is added to the DEPENDS section and exists for the current platform"
          )
      return jdk_dir
  
imports: import errno
  import functools
  import json
  import os
  import sys
  import threading
  import six
label_desc: Use image node_id 16 for calling a global function with example usage: java_home() and returns: jdk_dir