hazelcast::client::rb::read_result_set Class Reference

Public Member Functions
	read_result_set (int32_t read_count, std::vector< serialization::pimpl::data > &&data_items, serialization::pimpl::SerializationService &serialization_service, boost::optional< std::vector< int64_t >> &item_seqs, int64_t next_seq)
int32_t	read_count () const
	Returns the number of items that have been read before filtering. More...
const std::vector< typed_data > &	get_items () const
int64_t	get_sequence (int32_t index) const
	Return the sequence number for the item at the given index. More...
int64_t	get_next_sequence_to_read_from () const
	Returns the sequence of the item following the last read item. More...

Static Public Attributes
static const int64_t	SEQUENCE_UNAVAILABLE = -1
	Value returned from methods returning a sequence number when the information is not available (e.g. More...

Detailed Description

Definition at line 28 of file read_result_set.h.

Member Function Documentation

get_next_sequence_to_read_from()

int64_t hazelcast::client::rb::read_result_set::get_next_sequence_to_read_from ( ) const

inline

Returns the sequence of the item following the last read item.

This sequence can then be used to read items following the ones returned by this result set. Usually this sequence is equal to the sequence used to retrieve this result set incremented by the readCount(). In cases when the reader tolerates lost items, this is not the case. For instance, if the reader requests an item with a stale sequence (one which has already been overwritten), the read will jump to the oldest sequence and read from there. Similarly, if the reader requests an item in the future (e.g. because the partition was lost and the reader was unaware of this), the read method will jump back to the newest available sequence. Because of these jumps and only in the case when the reader is loss tolerant, the next sequence must be retrieved using this method. A return value of {@value SEQUENCE_UNAVAILABLE} means that the information is not available.

Returns

the sequence of the item following the last item in the result set

Since

3.10

Definition at line 107 of file read_result_set.h.

                                                               {
                    return next_seq_;
                }

get_sequence()

int64_t hazelcast::client::rb::read_result_set::get_sequence ( int32_t  index ) const

inline

Return the sequence number for the item at the given index.

Parameters

index

the index

Returns

the sequence number for the ringbuffer item

Exceptions

illegal_argument

if index out of bounds.

Since

3.9

Definition at line 75 of file read_result_set.h.

                                                          {
                    if (index >= (int32_t) item_seqs_->size() || index < 0) {
                        BOOST_THROW_EXCEPTION((exception::exception_builder<exception::illegal_argument>(
                                "read_result_set::getSequence") << "Index " << index
                                                              << " is out of bounds. Sequences size is:"
                                                              << item_seqs_->size()).build());
                    }
 
                    return (*item_seqs_)[index];
                }

read_count()

int32_t hazelcast::client::rb::read_result_set::read_count ( ) const

inline

Returns the number of items that have been read before filtering.

If no filter is set, then the

readCount 

will be equal to size. But if a filter is applied, it could be that items are read, but are filtered out. So if you are trying to make another read based on the read_result_set then you should increment the sequence by

readCount 

and not by size(). Otherwise you will be re-reading the same filtered messages.

Returns

the number of items read (including the filtered ones).

Definition at line 59 of file read_result_set.h.

                                           {
                    return items_read_count_;
                }

Member Data Documentation

SEQUENCE_UNAVAILABLE

const int64_t hazelcast::client::rb::read_result_set::SEQUENCE_UNAVAILABLE = -1

static

Value returned from methods returning a sequence number when the information is not available (e.g.

because of rolling upgrade and some members not returning the sequence).

Definition at line 35 of file read_result_set.h.

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The documentation for this class was generated from the following file:

• hazelcast/include/hazelcast/client/ringbuffer/read_result_set.h