Setting a specific Java version to maven if you've multiple Java versions installed in the system

This is for the macOS:

By default, maven runs with the default JAVA_HOME configured in the system. If you want to set a different Java version temporarily for your maven - we need to change the JAVA_HOME in the mvn file. 

mvn shell file

#!/bin/bash

JAVA_HOME="${JAVA_HOME:-$(/usr/libexec/java_home)}" exec "/usr/local/Cellar/maven/3.5.2/libexec/bin/mvn" "$@"

Changed mvn shell file this to:

#!/bin/bash

JAVA_HOME="/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home" exec "/usr/local/Cellar/maven/3.5.2/libexec/bin/mvn" "$@"

However, if you wish to set a particular java version to the project permanently - that needs to be configured in the pom.xml file

Refer here:                   

https://maven.apache.org/plugins/maven-compiler-plugin/examples/set-compiler-source-and-target.html

For example, to set for Java 1.8

<properties>

        <maven.compiler.target>1.8</maven.compiler.target>

        <maven.compiler.source>1.8</maven.compiler.source>

 </properties>

Java 7:

<properties>

        <maven.compiler.target>1.7</maven.compiler.target>

        <maven.compiler.source>1.7</maven.compiler.source>

 </properties>

 But where can I find this mvn file in macOS?

$ which mvn

/usr/local/bin/mvn

$ cat mvn

#!/bin/bash

JAVA_HOME="/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home" exec "/usr/local/Cellar/maven/3.5.2/libexec/bin/mvn" "$@"

As you can see - mvn file is located in /usr/local/Cellar/maven/3.5.2/libexec/bin/