Trouble getting Sonarqube to work with Jenkins. Throws "could not find 'java' executable in JAVA_HOME or PATH"

Question

Hi I am trying to get Sonarqube to work with Jenkins. I have jenkins running as a docker image and Sonarqube server running as two separate docker images on my host machine. I am using the SonarScanner plugin for Jenkins to scan my project. However, when I try to run the my pipeline the "/var/jenkins_home/tools/hudson.plugins.sonar.SonarRunnerInstallation/test/bin/sonar-scanner" bash script returns the error could not find 'java' executable in JAVA_HOME or PATH.

This is strange because I can successfully echo JAVA_HOME within my Jenkins container. However, when I try to echo within the bash script, it returns nothing. I also tried manually setting the JAVA_HOME variable within the script but found the script cant execute java. I also followed the advice from this post:

Jenkins pipeline for react could not find 'java' executable in JAVA_HOME or PATH

but it still does not work. Here is my Jenkins pipeline script

pipeline {
    agent {
        docker {
            image 'node:6-alpine'
            args '-p 3000:3000'
        }
    }
    environment { 
        CI = 'true'
        scannerHome = tool 'test'
    }
    stages {
        stage('Build') {
            steps {
                sh 'npm install'
            }
        }
        stage('SonarQube analysis') {
            agent{ docker { image 'openjdk' }  }
            steps{
                withSonarQubeEnv('sonar') { 
                    sh "${scannerHome}/bin/sonar-scanner"
                }
            }
        }
        stage('Test') {
            steps {
                sh './jenkins/scripts/test.sh'
            }
        }
        stage('Deliver') { 
            steps {
                sh './jenkins/scripts/deliver.sh' 
                input message: 'Finished using the web site? (Click "Proceed" to continue)' 
                sh './jenkins/scripts/kill.sh' 
            }
        }
    }
}