[FLINK-7032] Intellij is constantly changing language level of sub projects back to 1.6

• Type: Improvement
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 1.3.2, 1.4.0
• Component/s: Build System
• Assignee: Piotr Nowojski
• Reporter: Piotr Nowojski
• Created: 28/Jun/17 18:29
• Updated: 04/Jul/17 07:43
• Resolved: 04/Jul/17 07:35

Description

Every time I do maven reimport projects, Intellij is switching back to 1.6 language level. I tracked down this issue to misconfiguration in our pom.xml file. It correctly configure maven-compiler-plugin:

			<plugin>
				<!-- just define the Java version to be used for compiling and plugins -->
				<groupId>org.apache.maven.plugins</groupId>
				<artifactId>maven-compiler-plugin</artifactId>
				<version>3.1</version><!--$NO-MVN-MAN-VER$-->
				<configuration>
					<source>${java.version}</source>
					<target>${java.version}</target>
					<!-- The output of Xlint is not shown by default, but we activate it for the QA bot
					to be able to get more warnings -->
					<compilerArgument>-Xlint:all</compilerArgument>
				</configuration>
			</plugin>

where ${java.version} is set to 1.7 in the properties, but it forgets to overwrite the following properties from apache-18.pom:

  <properties>
    <maven.compiler.source>1.6</maven.compiler.source>
    <maven.compiler.target>1.6</maven.compiler.target>
  </properties>

It seems like compiling from console using maven ignores those values, but they are confusing Intellij.

Issue Links

• links to: GitHub Pull Request #4213