GMavenPlus bytecode error

July 29, 2022

What's inside this article ⌄

GMavenPlus unrecognized bytecode
GMavenPlus target version error
Fix GMavenPlus bytecode error
GMavenPlus compilation target

When you try to compile Groovy with Java and use gmavenplus plugin for that purpose, you may face with this errors:

Unrecognized target bytecode.
Unrecognized target bytecode '8'.
[ERROR] Failed to execute goal org.codehaus.gmavenplus:gmavenplus-plugin:1.6:compileTests (default) on project test: Execution default of goal org.codehaus.gmavenplus:gmavenplus-plugin:1.6:compileTests failed: Unrecognized target bytecode. -> [Help 1]

To solve this problem, you need to replace the 8 to 1.8 in your maven-compiler-plugin:

<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>

If you don’t have maven-compiler-plugin – add it to your project pom.xml, as shown above.