com.datastax.driver.core

Class AbstractSession

java.lang.Object

com.datastax.driver.core.AbstractSession

All Implemented Interfaces:

ContinuousPagingSession, Session, Closeable, AutoCloseable

public abstract class AbstractSession
extends Object
implements Session, ContinuousPagingSession

Abstract implementation of the Session interface.

This is primarly intended to make mocking easier.

Nested Class Summary

Nested classes/interfaces inherited from interface com.datastax.driver.core.Session

Session.State

Constructor Summary

Constructors

Constructor and Description
AbstractSession()

Method Summary

Modifier and Type	Method and Description
void	checkNotInEventLoop() Checks that the current thread is not one of the Netty I/O threads used by the driver.
void	close() Initiates a shutdown of this session instance and blocks until that shutdown completes.
ResultSet	execute(Statement statement) Executes the provided query.
ResultSet	execute(String query) Executes the provided query.
ResultSet	execute(String query, Map<String,Object> values) Executes the provided query using the provided named values.
ResultSet	execute(String query, Object... values) Executes the provided query using the provided values.
ResultSetFuture	executeAsync(String query) Executes the provided query asynchronously.
ResultSetFuture	executeAsync(String query, Map<String,Object> values) Executes the provided query asynchronously using the provided values.
ResultSetFuture	executeAsync(String query, Object... values) Executes the provided query asynchronously using the provided values.
protected Cluster	getConcreteCluster() Return the concrete Cluster instance driving the Session.
PreparedStatement	prepare(RegularStatement statement) Prepares the provided query.
PreparedStatement	prepare(String query) Prepares the provided query string.
ListenableFuture<PreparedStatement>	prepareAsync(RegularStatement statement) Prepares the provided query asynchronously.
ListenableFuture<PreparedStatement>	prepareAsync(String query) Prepares the provided query string asynchronously.
protected abstract ListenableFuture<PreparedStatement>	prepareAsync(String query, String keyspace, Map<String,ByteBuffer> customPayload) Prepares the provided query string asynchronously, sending along the provided custom payload, if any.

Methods inherited from class java.lang.Object

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

Methods inherited from interface com.datastax.driver.core.ContinuousPagingSession

executeContinuously, executeContinuouslyAsync

Methods inherited from interface com.datastax.driver.core.Session

closeAsync, executeAsync, getCluster, getLoggedKeyspace, getState, init, initAsync, isClosed

Constructor Detail

AbstractSession

public AbstractSession()

Method Detail

execute

public ResultSet execute(String query)

Executes the provided query.

This is a convenience method for execute(new SimpleStatement(query)).

Specified by:

execute in interface Session

Parameters:

query - the CQL query to execute.

Returns:

the result of the query. That result will never be null but can be empty (and will be for any non SELECT query).

execute

public ResultSet execute(String query,
                         Object... values)

Executes the provided query using the provided values.

This is a convenience method for execute(new SimpleStatement(query, values)).

Specified by:

execute in interface Session

Parameters:

query - the CQL query to execute.

values - values required for the execution of query. See SimpleStatement.SimpleStatement(String, Object...) for more details.

Returns:

the result of the query. That result will never be null but can be empty (and will be for any non SELECT query).

execute

public ResultSet execute(String query,
                         Map<String,Object> values)

Executes the provided query using the provided named values.

This is a convenience method for execute(new SimpleStatement(query, values)).

Specified by:

execute in interface Session

Parameters:

query - the CQL query to execute.

values - values required for the execution of query. See SimpleStatement.SimpleStatement(String, Map) for more details.

Returns:

the result of the query. That result will never be null but can be empty (and will be for any non SELECT query).

execute

public ResultSet execute(Statement statement)

Executes the provided query.

This method blocks until at least some result has been received from the database. However, for SELECT queries, it does not guarantee that the result has been received in full. But it does guarantee that some response has been received from the database, and in particular guarantees that if the request is invalid, an exception will be thrown by this method.

Specified by:

execute in interface Session

Parameters:

statement - the CQL query to execute (that can be any Statement).

Returns:

the result of the query. That result will never be null but can be empty (and will be for any non SELECT query).

executeAsync

public ResultSetFuture executeAsync(String query)

Executes the provided query asynchronously.

This is a convenience method for executeAsync(new SimpleStatement(query)).

Specified by:

executeAsync in interface Session

Parameters:

query - the CQL query to execute.

Returns:

a future on the result of the query.

executeAsync

public ResultSetFuture executeAsync(String query,
                                    Map<String,Object> values)

Executes the provided query asynchronously using the provided values.

This is a convenience method for executeAsync(new SimpleStatement(query, values)).

Specified by:

executeAsync in interface Session

Parameters:

query - the CQL query to execute.

values - values required for the execution of query. See SimpleStatement.SimpleStatement(String, Map) for more details.

Returns:

a future on the result of the query.

executeAsync

public ResultSetFuture executeAsync(String query,
                                    Object... values)

Executes the provided query asynchronously using the provided values.

This is a convenience method for executeAsync(new SimpleStatement(query, values)).

Specified by:

executeAsync in interface Session

Parameters:

query - the CQL query to execute.

values - values required for the execution of query. See SimpleStatement.SimpleStatement(String, Object...) for more details.

Returns:

a future on the result of the query.

prepare

public PreparedStatement prepare(String query)

Prepares the provided query string.

Specified by:

prepare in interface Session

Parameters:

query - the CQL query string to prepare

Returns:

the prepared statement corresponding to query.

prepare

public PreparedStatement prepare(RegularStatement statement)

Prepares the provided query.

This method behaves like Session.prepare(String), but the resulting PreparedStatement will inherit some of the properties set on statement: routing key, consistency level, serial consistency level, tracing flag, retry policy, outgoing payload, and idempotence. Concretely, this means that in the following code:

 RegularStatement toPrepare = new SimpleStatement("SELECT * FROM test WHERE k=?").setConsistencyLevel(ConsistencyLevel.QUORUM);
 PreparedStatement prepared = session.prepare(toPrepare);
 session.execute(prepared.bind("someValue"));
 

the final execution will be performed with Quorum consistency.

Please note that if the same CQL statement is prepared more than once, all calls to this method will return the same PreparedStatement object but the method will still apply the properties of the prepared Statement to this object.

Specified by:

prepare in interface Session

Parameters:

statement - the statement to prepare

Returns:

the prepared statement corresponding to statement.

prepareAsync

public ListenableFuture<PreparedStatement> prepareAsync(String query)

Prepares the provided query string asynchronously.

This method is equivalent to Session.prepare(String) except that it does not block but return a future instead. Any error during preparation will be thrown when accessing the future, not by this method itself.

Specified by:

prepareAsync in interface Session

Parameters:

query - the CQL query string to prepare

Returns:

a future on the prepared statement corresponding to query.

prepareAsync

public ListenableFuture<PreparedStatement> prepareAsync(RegularStatement statement)

Prepares the provided query asynchronously. This method behaves like Session.prepareAsync(String), but note that the resulting PreparedStatement will inherit the query properties set on statement. Concretely, this means that in the following code:

 RegularStatement toPrepare = new SimpleStatement("SELECT * FROM test WHERE k=?").setConsistencyLevel(ConsistencyLevel.QUORUM);
 PreparedStatement prepared = session.prepare(toPrepare);
 session.execute(prepared.bind("someValue"));
 

the final execution will be performed with Quorum consistency.

Please note that if the same CQL statement is prepared more than once, all calls to this method will return the same PreparedStatement object but the method will still apply the properties of the prepared Statement to this object.

Specified by:

prepareAsync in interface Session

Parameters:

statement - the statement to prepare

Returns:

a future on the prepared statement corresponding to statement.

See Also:

Session.prepare(RegularStatement)

prepareAsync

protected abstract ListenableFuture<PreparedStatement> prepareAsync(String query,
                                                                    String keyspace,
                                                                    Map<String,ByteBuffer> customPayload)

Prepares the provided query string asynchronously, sending along the provided custom payload, if any.

Parameters:

query - the CQL query string to prepare

keyspace - the keyspace to prepare this query with

customPayload - the custom payload to send along the query, or null if no payload is to be sent

Returns:

a future on the prepared statement corresponding to query.

close

public void close()

Initiates a shutdown of this session instance and blocks until that shutdown completes.

This method is a shortcut for closeAsync().get().

Note that this method does not close the corresponding Cluster instance (which holds additional resources, in particular internal executors that must be shut down in order for the client program to terminate). If you want to do so, use Cluster.close(), but note that it will close all sessions created from that cluster.

Specified by:

close in interface Session

Specified by:

close in interface Closeable

Specified by:

close in interface AutoCloseable

getConcreteCluster

protected Cluster getConcreteCluster()

Return the concrete Cluster instance driving the Session. This is useful to override in cases where the Session implementation is backed by DelegatingCluster.

Returns:

the concrete cluster instance backing this session.

checkNotInEventLoop

public void checkNotInEventLoop()

Checks that the current thread is not one of the Netty I/O threads used by the driver.

This method is called from all the synchronous methods of this class to prevent deadlock issues.

User code extending this class can also call this method at any time to check if any code making blocking calls is being wrongly executed on a Netty I/O thread.

Note that the check performed by this method has a small overhead; if that is an issue, checks can be disabled by setting the System property com.datastax.driver.CHECK_IO_DEADLOCKS to false.

Throws:

IllegalStateException - if the current thread is one of the Netty I/O thread used by the driver.