Is there a good way to get JAVA_HOME real path with Ansible?

Use Ansible to install Java as

- name: Install Java
  yum:
  ┆ name:
  ┆ ┆ - java-1.8.0-openjdk
  ┆ state: present

Then set JAVA_HOME environment variable in ~/.bash_profile

- name: Update .bash_profile
  copy:
  ┆ src: bash_profile
  ┆ dest: /home/user/.bash_profile
  ┆ owner: user

bash_profile as

...
export JAVA_HOME=/usr/lib/jvm/java-1.8.0-openjdk-1.8.0.232.b09-0.el7_7.x86_64/jre

But after a long time, when run the playbook to install Java again, its version maybe upgraded.
So the real path maybe change to other folder. Can't use Java correctly.

From this article, we can find this method can get Java's path

update-alternatives --config java
Selection    Command
-----------------------------------------------
*+ 1           java-1.8.0-openjdk.x86_64 (/usr/lib/jvm/java-1.8.0-openjdk-1.8.0.191.b12-1.el7_6.x86_64/jre/bin/java)</code?

Is it possible to find it from Ansible playbook?

You may use the following task to fetch the JAVA_HOME at runtime.

- name: "Fetch JAVA_HOME"
  shell: dirname $(dirname $(readlink -f $(which javac)))
  register: java_home

Below URL provided more way of finding JAVA_HOME:

Eg:

java -XshowSettings:properties -version 2>&1 |grep -oP 'java.home =\s\K.*'

More read: Original artical