DbService Class

Description

A class to provide the main services of the graph database by loading the configurations and exposing access to the Beans provided by spring-data-neo4j's factory.

It wraps the configuration class to consolidate the service in one class.

Package

persistence

Constructor

None defined in the class.

Static Members

private static final ApplicationContext ctx

Provides Bean-factory methods for accessing application components.

Attributes

None

Links

None

Protocol

This is a service class, hence all protocol is static.

Static Methods

protected static Neo4jTemplate getNeo4jTemplate()

Post condition: return a mediator object to access Neo4j services.

protected static GraphDatabaseService getGraphDb()

Post condition: return the singleton graphDb instance - exposing access lower than OGM.

protected static <T> T getRepository(Class<T> clazz)

Post condition: return A repository implementation for T -an instance. Loading a bean for a repository implementation in a generic fashion.

Inner Classes

DbConfig

A class for setting up spring-data-neo4j configurations for OGM.

Members

private static final String storeDirectory

Location of the embedded data store.

Protocol

GraphDatabaseService graphDatabaseService()

Provides an implementation of GraphDatabaseService as a Bean definition - required by Neo4jConfiguration.

Examples

Using a repository

private static final BookingRepository bookingRepo = 
                    DbService.getRepository(BookingRepository.class);

public static Booking perisitBooking(Booking aBooking)
{
    return bookingRepo.save(aBooking);
}

Using Neo4jTemplate

private static final Neo4jTemplate neo4jMediator = DbService.getNeo4jTemplate();

public static void persistEntity(EntityToSave anEntity)
{
    Transaction tx = DbService.getGraphDb().beginTx();
    try {
        neo4jMediator.save(anEntity);
        tx.success();
    } finally {
        tx.finish();
    }
}

Using lower level than OGM

public static void printAllNodes() 
{
    String out;
    for (Node n : GlobalGraphOperations.at(DbService.getGraphDb()).getAllNodes()) {
        if (n.hasProperty("__type__")) {
            out = "" + n.getId();
            for(String key: n.getPropertyKeys()) {
               out += "\t" + key + ": " + n.getProperty(key);
            }
            System.out.println(out);
        }
    }

}

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