# Could not find implementation class for plugin error when using plugin "java-gradle-plugin"

**URL:** <https://discuss.gradle.org/t/could-not-find-implementation-class-for-plugin-error-when-using-plugin-java-gradle-plugin/34042>\
**Category:** Help/Discuss\
**Created:** [November 28, 2019, 1:35am UTC](https://discuss.gradle.org/t/could-not-find-implementation-class-for-plugin-error-when-using-plugin-java-gradle-plugin/34042 "2019-11-28T01:35:33Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![ZillaG](https://avatars.discourse-cdn.com/v4/letter/z/ed655f/32.png) [@ZillaG](https://discuss.gradle.org/u/ZillaG)\
**Post date:** [November 28, 2019, 1:35am UTC](https://discuss.gradle.org/t/could-not-find-implementation-class-for-plugin-error-when-using-plugin-java-gradle-plugin/34042/1 "2019-11-28T01:35:33Z")

</div>

Gradle 4.10.2

I’ve read [this post](https://discuss.gradle.org/t/could-not-find-implementation-class-for-plugin-error-when-using-gradle-4-1/24279) but I may have a different issue, but I’m not sure.

This is my first time writing a plugin so I’m just following [Writing Gradle Plugins](https://guides.gradle.org/writing-gradle-plugins/) tutorial, and [Gradle Plugin Development Plugin](https://docs.gradle.org/4.10.3/userguide/java_gradle_plugin.html).

Here’s my plugin’s `build.gradle` file

```
apply plugin: 'java'
apply plugin: 'java-gradle-plugin'

gradlePlugin {
    plugins {
        simplePlugin {
            id = 'org.example.greeting-plugin'
            implementationClass = 'org.example.greeting.GreetingPlugin'
        }
    }
}

```

However when I get this when I build

```
$ ./gradlew clean build

**> Task :jar**

:jar: A valid plugin descriptor was found for org.example.greeting-plugin.properties but the implementation class org.example.greeting.GreetingPlugin was not found in the jar.

**BUILD SUCCESSFUL** in 0s

```

How can I fix it?

---

<div class="post-metadata">

**Author:** ![ZillaG](https://avatars.discourse-cdn.com/v4/letter/z/ed655f/32.png) [@ZillaG](https://discuss.gradle.org/u/ZillaG)\
**Post date:** [December 4, 2019, 12:07am UTC](https://discuss.gradle.org/t/could-not-find-implementation-class-for-plugin-error-when-using-plugin-java-gradle-plugin/34042/2 "2019-12-04T00:07:36Z")

</div>

The tutorial has the source code in the `/top-level/buildSrc/src...` tree. Once I moved it to the `/top-level/src/...` tree, it worked.