How do I update the Maven configuration in Eclipse Luna?

Question

I am using Java 8 for my JRE in Eclipse Luna with with the m2e Maven plugin. I see this warning as soon as I create a Maven project: Build path specifies execution environment J2SE-1.5. There are no JREs installed in the workspace that are strictly compatible with this environment. I see lots of older advice on this site on how to deal with this error, but nothing related to Java 8. I also that Oracle says J2SE was deprecated in 2008. The most promising answer I have found thus far comes from @Pascal Thivent here:

Warning - Build path specifies execution environment J2SE-1.4

But these instructions no longer seem to be relevant for Luna:

Eclipse project Properties > Maven > Update Project Configuration

I only see "Lifecycle mapping" under Maven.

enter image description here

Can someone please explain (1) what this error means (2) if it is still a worry, given that J2SE-1.5 seems to have been deprecated (3) how to best fix it in Luna?

I think you should update the POM first and then the m2e configuration for that project. (Probably something like this for Maven: http://maven.apache.org/enforcer/enforcer-rules/requireJavaVersion.html) — Gábor Bakos, Jan 05 '15 at 21:47
Its because you don't a JRE 5 installed in Eclipse: `Prefereces > Java > Installed JREs` — Mike R, Jan 05 '15 at 21:48
`Update Project Configuration` is in context menu of project in project panel under `maven` menu — msangel, Jan 05 '15 at 21:50
@JigarJoshi but I need JRE 8 for some of the jars in my project — bernie2436, Jan 05 '15 at 22:04
ok then change your pom.xml to have compiler plugin to use 1.8 as source and target and change your installed JRE to point to JDk 1.8 — jmj, Jan 05 '15 at 22:05
@JigarJoshi is this what I need to set in my pom.xml? http://maven.apache.org/plugins/maven-compiler-plugin/examples/set-compiler-source-and-target.html — bernie2436, Jan 05 '15 at 22:09

score 2 · Accepted Answer · edited Jan 05 '15 at 22:17

This error is because the project pom file is instructing maven to compile against java 1.5.
It is best to compile and test to a current java version. In your case java 8.

I am unsure how to fix it inside the eclipse IDE, but the project pom file can be edited to include the compile version as follows:

<plugin>  
  <groupId>org.apache.maven.plugins</groupId>    
  <artifactId>maven-compiler-plugin</artifactId>    
  <version>3.1</version>    
  <configuration>    
    <source>1.8</source>    
    <target>1.8</target>    
  </configuration>    
</plugin>

How do I update the Maven configuration in Eclipse Luna?

1 Answers1