Package org.hobbit.storage.client

Class StorageServiceClient

java.lang.Object

org.hobbit.storage.client.StorageServiceClient

All Implemented Interfaces:

Closeable, AutoCloseable

public class StorageServiceClient
extends Object
implements Closeable

Simple client of the storage service implementing a synchronized communication.

Author:

Michael Röder (roeder@informatik.uni-leipzig.de)

Field Summary

Fields

Modifier and Type	Field	Description
private static long	DEFAULT_MAX_WAITING_TIME	The default maximum amount of time in millisecond the client is waiting for a response = ms.
private static org.slf4j.Logger	LOGGER
private RabbitRpcClient	rpcClient	RPC client that is used for the communication.

Constructor Summary

Constructors

Constructor	Description
StorageServiceClient(RabbitRpcClient rpcClient)	Constructor creating a StorageServiceClient using the given RabbitRpcClient.

Method Summary

Modifier and Type	Method	Description
void	close()
static StorageServiceClient	create(com.rabbitmq.client.Connection connection)	Creates a StorageServiceClient using the given RabbitMQ Connection.
boolean	sendAskQuery(String query)	Sends the given ASK query to the storage service and returns a boolean value or throws an Exception if an error occurs, the service needs too much time to respond or the response couldn't be parsed.
org.apache.jena.rdf.model.Model	sendConstructQuery(String query)	Sends the given CONSTRUCT query to the storage service and returns a Model value or null if an error occurs, the service needs too much time to respond or the response couldn't be parsed.
org.apache.jena.rdf.model.Model	sendDescribeQuery(String query)	Sends the given DESCRIBE query to the storage service and returns a Model value or null if an error occurs, the service needs too much time to respond or the response couldn't be parsed.
boolean	sendInsertQuery(org.apache.jena.rdf.model.Model model, String graphURI)	Inserts the given model into the storage and returns true if the query is successful or false if an error occurs or the service needs too much time to respond.
org.apache.jena.query.ResultSet	sendSelectQuery(String query)	Sends the given SELECT query to the storage service and returns a ResultSet value or null if an error occurs, the service needs too much time to respond or the response couldn't be parsed.
boolean	sendUpdateQuery(String query)	Sends the given UPDATE query to the storage service and returns true if the query is successful or false if an error occurs or the service needs too much time to respond.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

LOGGER

private static final org.slf4j.Logger LOGGER

DEFAULT_MAX_WAITING_TIME

private static final long DEFAULT_MAX_WAITING_TIME

The default maximum amount of time in millisecond the client is waiting for a response = ms.

See Also:

Constant Field Values

rpcClient

private RabbitRpcClient rpcClient

RPC client that is used for the communication.

Constructor Detail

StorageServiceClient

public StorageServiceClient(RabbitRpcClient rpcClient)

Constructor creating a StorageServiceClient using the given RabbitRpcClient.

Parameters:

rpcClient - RPC client that is used for the communication

Method Detail

create

public static StorageServiceClient create(com.rabbitmq.client.Connection connection)
                                   throws IOException

Creates a StorageServiceClient using the given RabbitMQ Connection.

Parameters:

connection - RabbitMQ connection used for the communication

Returns:

a StorageServiceClient instance

Throws:

IOException - if a problem occurs during the creation of the queues or the consumer.

sendAskQuery

public boolean sendAskQuery(String query)
                     throws Exception

Sends the given ASK query to the storage service and returns a boolean value or throws an Exception if an error occurs, the service needs too much time to respond or the response couldn't be parsed.

Parameters:

query - ASK query

Returns:

result for the query or false if an error occurs

Throws:

Exception - if no response has been received or the response couldn't be parsed.

sendConstructQuery

public org.apache.jena.rdf.model.Model sendConstructQuery(String query)

Sends the given CONSTRUCT query to the storage service and returns a Model value or null if an error occurs, the service needs too much time to respond or the response couldn't be parsed.

Parameters:

query - CONSTRUCT query

Returns:

result for the query or null

sendDescribeQuery

public org.apache.jena.rdf.model.Model sendDescribeQuery(String query)

Sends the given DESCRIBE query to the storage service and returns a Model value or null if an error occurs, the service needs too much time to respond or the response couldn't be parsed.

Parameters:

query - DESCRIBE query

Returns:

result for the query or null

sendSelectQuery

public org.apache.jena.query.ResultSet sendSelectQuery(String query)

Sends the given SELECT query to the storage service and returns a ResultSet value or null if an error occurs, the service needs too much time to respond or the response couldn't be parsed.

Parameters:

query - SELECT query

Returns:

result for the query or null

sendUpdateQuery

public boolean sendUpdateQuery(String query)

Sends the given UPDATE query to the storage service and returns true if the query is successful or false if an error occurs or the service needs too much time to respond.

Parameters:

query - UPDATE query

Returns:

flag indicating whether the query has been executed successfully or not

sendInsertQuery

public boolean sendInsertQuery(org.apache.jena.rdf.model.Model model,
                               String graphURI)

Inserts the given model into the storage and returns true if the query is successful or false if an error occurs or the service needs too much time to respond.

Parameters:

model - RDF model containing triples that should be inserted

graphURI - URI of the graph in which the model should be inserted

Returns:

flag indicating whether the query has been executed successfully or not

close

public void close()
           throws IOException

Closes the internal rpcClient instance.

Specified by:

close in interface AutoCloseable

Specified by:

close in interface Closeable

Throws:

IOException