Setting up a remote repository

Setting up the server part of the JCR-RMI layer is quite straightforward. After instantiating a local JCR repository you need to wrap it into a remote adapter and create an RMI binding for the repository. A variation of the following code is usually all that is needed in addition to the standard RMI setup (starting rmiregistry, etc.):

Repository repository = ...; // The local repository
String name = ...; // The RMI URL for the repository
    
RemoteAdapterFactory factory = new ServerAdapterFactory();
RemoteRepository remote = factory.getRemoteRepository(repository);
Naming.bind(name, remote);  // Make the RMI binding using java.rmi.Naming

Accessing a remote repository

The ClientRepositoryFactory class provides a convenient mechanism for looking up a remote JCR-RMI repository. The factory can be used either directly or as a JNDI object factory.

The following example shows how to use the ClientRepositoryFactory directly:

String name = ...; // The RMI URL of the repository
    
ClientRepositoryFactory factory = new ClientRepositoryFactory();
Repository repository = factory.getRepository(name);

The ClientRepositoryFactory can also be used via JNDI. The following example settings and code demonstrate how to configure and use the transparent JCR-RMI layer in a Tomcat 5.5 web application:

context.xml:

<Resource name="jcr/Repository" auth="Container"
    type="javax.jcr.Repository"
    factory="org.apache.jackrabbit.rmi.client.ClientRepositoryFactory"
    url="..."/>

web.xml:

<resource-env-ref>
  <description>The external content repository</description>
  <resource-env-ref-name>jcr/Repository</resource-env-ref-name>
  <resource-env-ref-type>javac.jcr.Repository</resource-env-ref-type>
</resource-env-ref>

…SomeServlet.java:

Context initial = new InitialContext();
Context context = (Context) initial.lookup("java:comp/env");
Repository repository = (Repository) context.lookup("jcr/Repository");

Note that in the example above only the context.xml configuration file contains a direct references to the JCR-RMI layer. All other parts of the web application can be implemented using the standard JCR interfaces.