2.7

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void

cass_future_free

( future )

Frees a future instance. A future can be freed anytime.

Parameters:

Name	Type	Details
future

CassError

cass_future_set_callback

( future, callback, data )

Sets a callback that is called when a future is set

Parameters:

Name	Type	Details
in future
in callback
in data

Returns:

Type	Details
CassError	CASS_OK if successful, otherwise an error occurred

cass_bool_t

cass_future_ready

( future )

Gets the set status of the future.

Parameters:

Name	Type	Details
in future

Returns:

Type	Details
cass_bool_t	true if set

void

cass_future_wait

( future )

Wait for the future to be set with either a result or error.

Important: Do not wait in a future callback. Waiting in a future callback will cause a deadlock.

Parameters:

Name	Type	Details
in future

cass_bool_t

cass_future_wait_timed

( future, timeout_us )

Wait for the future to be set or timeout.

Parameters:

Name	Type	Details
in future
in timeout_us	wait time in microseconds

Returns:

Type	Details
cass_bool_t	false if returned due to timeout

const CassResult *

cass_future_get_result

( future )

Gets the result of a successful future. If the future is not ready this method will wait for the future to be set.

Parameters:

Name	Type	Details
in future

Returns:

Type	Details
const CassResult *	CassResult instance if successful, otherwise NULL for error. The return instance must be freed using CassResult::cass_result_free .

See Also:

• CassSession::cass_session_execute and CassSession::cass_session_execute_batch

const CassErrorResult *

cass_future_get_error_result

( future )

Gets the error result from a future that failed as a result of a server error. If the future is not ready this method will wait for the future to be set.

Parameters:

Name	Type	Details
in future

Returns:

Type	Details
const CassErrorResult *	CassErrorResult instance if the request failed with a server error, otherwise NULL if the request was successful or the failure was not caused by a server error. The return instance must be freed using CassErrorResult::cass_error_result_free .

See Also:

• CassSession::cass_session_execute and CassSession::cass_session_execute_batch

const CassPrepared *

cass_future_get_prepared

( future )

Gets the result of a successful future. If the future is not ready this method will wait for the future to be set. The first successful call consumes the future, all subsequent calls will return NULL.

Parameters:

Name	Type	Details
in future

Returns:

Type	Details
const CassPrepared *	CassPrepared instance if successful, otherwise NULL for error. The return instance must be freed using CassPrepared::cass_prepared_free .

See Also:

• CassSession::cass_session_prepare

CassError

cass_future_error_code

( future )

Gets the error code from future. If the future is not ready this method will wait for the future to be set.

Parameters:

Name	Type	Details
in future

Returns:

Type	Details
CassError	CASS_OK if successful, otherwise an error occurred.

See Also:

• cass_error_desc

void

cass_future_error_message

( future, message, message_length )

Gets the error message from future. If the future is not ready this method will wait for the future to be set.

Parameters:

Name	Type	Details
in future
out message	Empty string returned if successful, otherwise a message describing the error is returned.
out message_length

size_t

cass_future_custom_payload_item_count

( future )

Gets a the number of custom payload items from a response future. If the future is not ready this method will wait for the future to be set.

Requires Cassandra: 2.2+

Parameters:

Name	Type	Details
in future

Returns:

Type	Details
size_t	the number of custom payload items.

CassError

cass_future_custom_payload_item

( future, index, name, name_length, value, value_size )

Gets a custom payload item from a response future at the specified index. If the future is not ready this method will wait for the future to be set.

Requires Cassandra: 2.2+

Parameters:

Name	Type	Details
in future
in index
out name
out name_length
out value
out value_size

Returns:

Type	Details
CassError	CASS_OK if successful, otherwise an error occurred.