example-toolchains.xml

<?xml version="1.0" encoding="UTF8"?>
<toolchains>
  <!-- place this file in ${user.home}/.m2/toolchains.xml -->
  <!-- adjust the paths to jdkhome -->

  <toolchain>
    <type>jdk</type>
    <provides>
      <version>1.7</version>
    </provides>
    <configuration>
      <jdkHome>/path/to/jdk/1.7</jdkHome>                                                   <!-- Linux -->
      <jdkHome>/Library/Java/JavaVirtualMachines/jdk1.7.0_80.jdk/Contents/Home</jdkHome>    <!-- MacOSX -->
      <jdkHome>C:\\java\\edition\\jdk1.7.0_80</jdkHome>                                     <!-- Windows -->
    </configuration>
  </toolchain>
  <toolchain>
    <type>jdk</type>
    <provides>
      <version>1.8</version>
    </provides>
    <configuration>
      <jdkHome>/path/to/jdk/1.8</jdkHome>                                                   <!-- Linux -->
      <jdkHome>/Library/Java/JavaVirtualMachines/jdk1.8.0_131.jdk/Contents/Home</jdkHome>   <!-- MacOSX -->
      <jdkHome>C:\\java\\edition\\jdk1.8.0_131</jdkHome>                                    <!-- Windows -->
    </configuration>
  </toolchain>
</toolchains>