Maven use Java 8 (or any other specific version) for project compilation and execution

10 Jan 2018

There are 2 ways for setting compiler `source` and `target` java versions:

1. Configuring corresponding project properties:

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

2. Configuring compile plugin:

<project>
  [...]
  <build>
    [...]
    <plugins>
      <plugin>
        <groupId>org.apache.maven.plugins</groupId>
        <artifactId>maven-compiler-plugin</artifactId>
        <version>3.7.0</version>
        <configuration>
          <source>1.8</source>
          <target>1.8</target>
        </configuration>
      </plugin>
    </plugins>
    [...]
  </build>
  [...]
</project>

Default java version for compiler plugin is 1.5
More details in documentation.