title: How does maven know JAVA_HOME set as an environment variable inUbuntu
body: <p>When I type mvn --version in ubuntu from the terminal(ubuntu),I get the below output.</p>
  
  <pre><code>Warning: JAVA_HOME environment variable is not set.
  Apache Maven 3.0.5
  Maven home: /usr/share/maven
  Java version: 1.7.0_79, vendor: Oracle Corporation
  Java home: /usr/lib/jvm/java-7-openjdk-amd64/jre
  Default locale: en_IN, platform encoding: UTF-8
  OS name: "linux", version: "3.13.0-32-generic", arch: "amd64", family:     "unix"
  </code></pre>
  
  <p>When I did not set any JAVA_HOME environment variable , how is maven getting the java home installed path.Is it trying to find this path from the /usr/bin/java command which is installed in my system and if so why is it taking the path till jre.</p>
  
  <p>P.S : Also I could not find any java path in any maven config.</p>
  
  <p>Thanks.</p>