# Command line (java -jar)

## Java version (important)

You need to make sure that you have Java 11 or 17 and that, if you have several versions installed, JAVA\_HOME correctly points to Java 11 or 17.

RumbleDB works with both Java 11 and Java 17. You can check the Java version that is configured on your machine with:

```
java -version
```

If you do not have Java, you can download version 11 or 17 from [AdoptOpenJDK](https://adoptopenjdk.net/).

Do make sure it is not Java 8, which will not work.

## Download RumbleDB

RumbleDB is just a download and no installation is required.

In order to run RumbleDB, you simply need to download rumbledb-2.1.0-standalone.jar from the [download page](https://github.com/RumbleDB/rumble/releases) and put it in a directory of your choice, for example, right besides your data.

Make sure to use the corresponding jar name accordingly in all our instructions in lieu of rumbledb.jar.

You can test that it works with:

```
java -jar rumbledb-2.1.0-standalone.jar run -q '1+1'
```

or launch a JSONiq shell with:

```
java -jar rumbledb-2.1.0-standalone.jar repl
```

If you run out of memory, you can set allocate more memory to Java with an additional Java parameter, e.g., -Xmx10g

The RumbleDB shell appears:

```
    ____                  __    __     ____  ____ 
   / __ \__  ______ ___  / /_  / /__  / __ \/ __ )
  / /_/ / / / / __ `__ \/ __ \/ / _ \/ / / / __  |  The distributed JSONiq engine
 / _, _/ /_/ / / / / / / /_/ / /  __/ /_/ / /_/ /   2.1.0 "Cedrus Libani" beta
/_/ |_|\__,_/_/ /_/ /_/_.___/_/\___/_____/_____/  


Master: local[*]
Item Display Limit: 200
Output Path: -
Log Path: -
Query Path : -

rumble$
```

You can now start typing simple queries like the following few examples. Press *three times* the return key to execute a query.

```
"Hello, World"
```

or

```
 1 + 1
 
```

or

```
 (3 * 4) div 5
 
```

Javadoc

If you plan to add the jar to your Java environment to use RumbleDB in your Java programs, the JavaDoc documentation can be found [here](https://rumbledb.org/docs/latest/api/). The entry point is the class org.rumbledb.api.Rumble.


---

# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://docs.rumbledb.org/getting-started/command-line-java-jar.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.