Java Bitcoind RPC Client is a lightweight Java bitcoin JSON-RPC client binding. It does not require any external dependencies.
It simply a repackaging of the original tool described here https://en.bitcoin.it/wiki/Bitcoin-JSON-RPC-Client with some small improvements.
The package is published in the wf.bitcoin group and you can add it to you pom.xml adding a section like this:
<dependency>
<groupId>wf.bitcoin</groupId>
<artifactId>JavaBitcoindRpcClient</artifactId>
<version>0.9.13</version>
</dependency>