Enable Assertions and other JVM 5.0 features supported by IDEA

IntelliJ IDEA supports JVM 5.0 and its new features. These are not enabled by default if the JVM running is less than 1.5. To enable them, you can use the following command:

mvn idea:idea -DjdkLevel=1.5

or in your pom.xml:

<project>
  [...]
  <build>
    [...]
    <plugins>
      [...]
      <plugin>
        <groupId>org.apache.maven.plugins</groupId>
        <artifactId>maven-idea-plugin</artifactId>
        <version>2.2.1</version>
        <configuration>
          <jdkLevel>1.5</jdkLevel>
        </configuration>
      </plugin>
      [...]
    </plugins>
    [...]
  </build>
  [...]
</project>