Kivy Apk build with buildozer error: # Java compiler (javac) not found, please install it

I'm trying to build an apk of my kivy project. I have installed buildozer in python 2.7 Using PyCharm, then I built the .spec, but when I tried to create the apk, I got these results: i have insatalled jdk7 and 8

1. Using: buildozer Android debug

   #Check configuration tokens
   # Ensure build layout
   # Check configuration tokens
   # Preparing build
   # Check requirements for android
   # Java compiler (javac) not found, please install it.
   

2. Using:  buildozer -v Android debug

   # Check configuration tokens
   # Ensure build layout
   # Check configuration tokens
   # Read available permissions from api-versions.xml
   # Preparing build
   # Check requirements for android
   # Run 'dpkg --version'
   # Cwd None
   /bin/sh: dpkg: comando non trovato
   # Search for Git (git)
   #  -> found at /usr/bin/git
   # Search for Cython (cython)
   #  -> found at /usr/bin/cython
   # Search for Java compiler (javac)
   # Java compiler (javac) not found, please install it.
   

3. Using: buildozer Android debug deploy run

   # Check configuration tokens
   # Ensure build layout
   # Check configuration tokens
   # Preparing build
   # Check requirements for android
   # Java compiler (javac) not found, please install it.
   

How do I get this to work?

The error seems fairly explicit - install javac.

This is probably in a java related package of your distro's package manager. It probably has search functionality to find the one you want.