on Ubuntu bionic beaver, it will fail to install because of Java 10 about ansible-role-elasticsearch HOT 2 CLOSED

---
# This avoids the java10 error: 'Unrecognized VM option 'UseParNewGC'
# for elasticsearch
# c.f. https://stackoverflow.com/questions/49623648/logstash-with-java10-get-error-unrecognized-vm-option-useparnewgc
# in a manner similar to the way elastic.elasticsearch handles it
# c.f. https://github.com/elastic/ansible-elasticsearch/blob/master/tasks/java.yml for redhat
- name: downgrade to 1.8 if available (Debian)
  block: 
  - name: Get the installed java path (for Debian)
    shell: "update-alternatives --display java | grep '^/' | awk '{print $1}' | grep java-8 | head -1"
    become: yes
    register: java_full_path
    failed_when: false
    changed_when: false
  - name: set java alternatives to 1.8
    alternatives:
      name: java
      path: "{{ java_full_path.stdout }}"
      link: /usr/bin/java
    when: java_full_path is defined
  when: ansible_os_family == 'Debian'
- name: downgrade to 1.8 if available (RedHat)
  block: 
  - name: Get the installed java path (for RedHat)
    shell: "update-alternatives --display java | grep '^/' | awk '{print $1}' | grep 1.8.0 | head -1"
    become: yes
    register: java_full_path
    failed_when: false
    changed_when: false
  - name: set java alternatives to 1.8
    alternatives:
      name: java
      path: "{{ java_full_path.stdout }}"
      link: /usr/bin/java
    when: java_full_path is defined
  when: ansible_os_family == 'RedHat'