how to change java version in pom.xml

<project>
...
 <properties>
    <maven.compiler.source>1.8</maven.compiler.source>
    <maven.compiler.target>1.8</maven.compiler.target>
  </properties>
...
</project>

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