# Stardog Home Lock Error & NoClassDefFoundError

**URL:** <https://community.stardog.com/t/stardog-home-lock-error-noclassdeffounderror/3297>\
**Category:** Support\
**Created:** [October 4, 2021, 4:07pm UTC](https://community.stardog.com/t/stardog-home-lock-error-noclassdeffounderror/3297 "2021-10-04T16:07:24Z")\
**Posts on this page:** 2\
**Page:** 1

<div class="post-metadata">

**Author:** ![turgutcilsal](https://avatars.discourse-cdn.com/v4/letter/t/4491bb/32.png) [@turgutcilsal](https://community.stardog.com/u/turgutcilsal)\
**Post date:** [October 4, 2021, 4:07pm UTC](https://community.stardog.com/t/stardog-home-lock-error-noclassdeffounderror/3297/1 "2021-10-04T16:07:25Z")

</div>

Hi,  
I'm trying to adopt the latest version of Stardog(7.7.2) for a Maven Project. I can build the project successfully, however, then when I try a simple Java code for starting a connection, add&drop a Database, and disconnect, I receive either one of the errors below:

> Stardog home is currently locked, cannot start kernel. Multiple instances of Stardog cannot use the same home directory.  
> Shut down the running Stardog server before starting another. The process ID for a running Stardog server is stored in the  
> stardog.pid file under STARDOG\_HOME directory. If that file does not exist, you can use standard system tools to find the process holding the lock on.

OR

> Exception in thread "main" java.lang.NoClassDefFoundError: com/google/common/util/concurrent/internal/InternalFutureFailureAccess

Can you help me regarding what would be the reason for that? All the directories work well and I can start the Server on .cmd or Stardog Studio, but just cannot do it on IntelliJ, via Java code.

My code is as follows:

> ```
> public static void main(String[] args) {
> Stardog aStardog = Stardog.builder().create();
> try {
> AdminConnection aAdminConnection = AdminConnectionConfiguration.toEmbeddedServer()
> .credentials("admin","admin").connect();
> aAdminConnection.newDatabase("new").create();
> aAdminConnection.drop("new");
> 
> } catch (Exception e){
> e.printStackTrace();
> } finally {
> aStardog.shutdown();
> }
> }
> 
> ```

The dependencies:

```
    <dependency>
        <groupId>com.complexible.stardog</groupId>
        <artifactId>server</artifactId>
        <version>7.7.2</version>
        <scope>compile</scope>
        <type>pom</type>
    </dependency>

    <dependency>
        <groupId>com.complexible.stardog.cache</groupId>
        <artifactId>stardog-cache-core</artifactId>
        <version>7.7.2</version>
        <scope>compile</scope>
    </dependency>

    <dependency>
        <groupId>com.stardog.stark.io</groupId>
        <artifactId>stardog-stark-io-api</artifactId>
        <version>7.7.2</version>
        <scope>compile</scope>
    </dependency>

    <dependency>
        <groupId>com.stardog.stark.query</groupId>
        <artifactId>stardog-stark-query-api</artifactId>
        <version>7.7.2</version>
        <scope>compile</scope>
    </dependency>

    <dependency>
        <groupId>com.stardog.stark.query.io</groupId>
        <artifactId>stardog-stark-query-io</artifactId>
        <version>7.7.2</version>
        <scope>compile</scope>
    </dependency>

    <dependency>
        <groupId>com.complexible.stardog</groupId>
        <artifactId>client-embedded</artifactId>
        <version>7.7.2</version>
        <scope>compile</scope>
    </dependency>

    <dependency>
        <groupId>com.complexible.stardog</groupId>
        <artifactId>client-http</artifactId>
        <version>7.7.2</version>
        <scope>compile</scope>
        <type>pom</type>
    </dependency>

    <dependency>
        <groupId>com.complexible.stardog.rdf4j</groupId>
        <artifactId>stardog-rdf4j</artifactId>
        <version>7.7.2</version>
        <scope>compile</scope>
    </dependency>

    <dependency>
        <groupId>org.eclipse.rdf4j</groupId>
        <artifactId>rdf4j-runtime</artifactId>
        <version>2.2.4</version>
    </dependency>

    <dependency>
        <groupId>com.complexible.stardog.jena</groupId>
        <artifactId>stardog-jena</artifactId>
        <version>7.7.2</version>
        <scope>compile</scope>
    </dependency>

</dependencies>

<repositories>
    <repository>
        <id>stardog-public</id>
        <url>https://maven.stardog.com</url>
    </repository>
</repositories>

```

Thanks in advance!

---

<div class="post-metadata">

**Author:** ![system](https://canada1.discourse-cdn.com/flex030/uploads/stardog/original/2X/e/ed66b48a616f505106a4acde3c9cee7e6da9bc67.svg) [@system](https://community.stardog.com/u/system)\
**Post date:** [October 18, 2021, 4:07pm UTC](https://community.stardog.com/t/stardog-home-lock-error-noclassdeffounderror/3297/2 "2021-10-18T16:07:31Z")

</div>

This topic was automatically closed 14 days after the last reply. New replies are no longer allowed.