Guice Integration

The folliwing is just a simple example on how you can inject Hector keyspaces through Google Guice

HectorModule example

This example assume there is a app.properties file in the path

public class HectorModule extends AbstractModule {

    private static final Logger log = LoggerFactory.getLogger(DAOModule.class);

    private static final String PROP_CASSANDRA_HOST_PORT = "CASSANDRA_HOST_PORT";

    private static final String DEFAULT_CASSANDRA_HOST_PORT = "127.0.0.1:9160";
    private static final String KEYSPACE = "RIQ";
    private static final String CLUSTER_NAME = "Test Cluster";

    private String propertyFileSuffix;
    private Properties properties;

    // private static Properties props;

    public HectorModule() {}

    @Override
    protected void configure() {

        // load properties
        properties = ConfigLoader.loadProperties(propertyFileSuffix);

        // bind so we can retrieve them elsewhere
        Names.bindProperties(binder(), properties);
    }

    @Singleton
    @Provides
    Properties provideProperties() {
        return properties;
    }


    @Singleton
    @Provides
    Keyspace provideKeyspace() {
        CassandraHostConfigurator chc = null;
        // Create the cluster
        if (properties.getProperty(PROP_CASSANDRA_HOST_PORT) != null || !properties.getProperty(PROP_CASSANDRA_HOST_PORT).equals("")) {
            chc = new CassandraHostConfigurator(properties.getProperty(PROP_CASSANDRA_HOST_PORT));
        } else {
            log.error("Unable to load cassandra host/port from properties; defaulting to " + DEFAULT_CASSANDRA_HOST_PORT);
            chc = new CassandraHostConfigurator(DEFAULT_CASSANDRA_HOST_PORT);
        }

        chc.setAutoDiscoverHosts(true);
        chc.setRetryDownedHosts(true);

        Cluster cluster = HFactory.getOrCreateCluster(CLUSTER_NAME, chc);

        // Create the long-life Keyspace object
        Keyspace keyspace = HFactory.createKeyspace(KEYSPACE, cluster);

        ConfigurableConsistencyLevel cp = new ConfigurableConsistencyLevel();
        cp.setDefaultReadConsistencyLevel(HConsistencyLevel.QUORUM);
        cp.setDefaultWriteConsistencyLevel(HConsistencyLevel.QUORUM);
        keyspace.setConsistencyLevelPolicy(cp);

        return keyspace;
    }

}

And you would typically have a DAO like this

public class MyDAO extends MyIFaceDAO {

    protected final Keyspace keyspace;

    @Inject
    public MyDAO(Keyspace keyspace) {
        this.keyspace = keyspace;
    }
}