Enterprise Java

Maven, Eclipse and Java 9

Anyone that uses the M2E(maven-to-eclipse) plugin in eclipse knows the issue where you have run a build, then update maven on your project only to have it reset the JRE and throw up a wall of project errors! I noticed the issue in the post I made on running Java EE 8 with Java 9 using Open Liberty

The solution is to ensure the compiler is running the correct version you require, so


Or –


There is a further point worth noting if you are using Java 9 or later, as the version number format is different. So while Java 8 has a version of 1.8, Java 9 has a version of 9

Java 9 vs Java 8 versions

This means you need to state the version in your pom as


Or using the full version in my JavaEE8 project(https://github.com/farrelmr/javaee8/blob/master/pom.xml) this would be stated as –

 xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">

This will prevent the problem in eclipse

This post may seem obvious – but it is worth stating that the change in version number for Java 9 means you must check you are using the correct version number in maven

Published on Java Code Geeks with permission by Martin Farrell, partner at our JCG program. See the original article here: Maven, Eclipse and Java 9

Opinions expressed by Java Code Geeks contributors are their own.

Martin Farrell

Martin is a Software Developer and Consultant specializing in Java and the Spring Framework. When not coding he spends time with his wife and two children, or cycling his bike.
Notify of

This site uses Akismet to reduce spam. Learn how your comment data is processed.

Inline Feedbacks
View all comments
Back to top button