Package org.apache.cassandra.service.pager

Class SinglePartitionPager

java.lang.Object
org.apache.cassandra.service.pager.SinglePartitionPager
All Implemented Interfaces:
QueryPager
public class SinglePartitionPager extends Object
Common interface to single partition queries (by slice and by name). For use by MultiPartitionPager.

  • Field Details

  • Constructor Details

  • Method Details

    • withUpdatedLimit

      public SinglePartitionPager withUpdatedLimit(DataLimits newLimits)
      Description copied from interface: QueryPager
      Creates a new QueryPager that use the new limits.
      Parameters:
      newLimits - the new limits
      Returns:
      a new QueryPager that use the new limits

    • key

      public ByteBuffer key()

    • limits

      public DataLimits limits()

    • state

      public PagingState state()
      Description copied from interface: QueryPager
      Get the current state of the pager. The state can allow to restart the paging on another host from where we are at this point.
      Returns:
      the current paging state. Will return null if paging is at the beginning. If the pager is exhausted, the result is undefined.

    • nextPageReadQuery

      protected SinglePartitionReadQuery nextPageReadQuery(int pageSize)

    • recordLast

      protected void recordLast(DecoratedKey key, Row last)

    • isPreviouslyReturnedPartition

      protected boolean isPreviouslyReturnedPartition(DecoratedKey key)

    • executionController

      public ReadExecutionController executionController()
      Description copied from interface: QueryPager
      Starts a new read operation.

      This must be called before QueryPager.fetchPageInternal(int,org.apache.cassandra.db.ReadExecutionController) and passed to it to protect the read. The returned object must be closed on all path and it is thus strongly advised to use it in a try-with-ressource construction.

      Specified by:
      executionController in interface QueryPager
      Returns:
      a newly started order group for this QueryPager.

    • fetchPage

      public PartitionIterator fetchPage(int pageSize, ConsistencyLevel consistency, ClientState clientState, Dispatcher.RequestTime requestTime)
      Description copied from interface: QueryPager
      Fetches the next page.
      Specified by:
      fetchPage in interface QueryPager
      Parameters:
      pageSize - the maximum number of elements to return in the next page.
      consistency - the consistency level to achieve for the query.
      clientState - the ClientState for the query. In practice, this can be null unless consistency is a serial consistency.
      Returns:
      the page of result.

    • fetchPageInternal

      public PartitionIterator fetchPageInternal(int pageSize, ReadExecutionController executionController)
      Description copied from interface: QueryPager
      Fetches the next page internally (in other, this does a local query).
      Specified by:
      fetchPageInternal in interface QueryPager
      Parameters:
      pageSize - the maximum number of elements to return in the next page.
      executionController - the ReadExecutionController protecting the read.
      Returns:
      the page of result.

    • fetchPageUnfiltered

      public UnfilteredPartitionIterator fetchPageUnfiltered(TableMetadata metadata, int pageSize, ReadExecutionController executionController)

    • restoreState

      protected void restoreState(DecoratedKey lastKey, int remaining, int remainingInPartition)

    • isExhausted

      public boolean isExhausted()
      Description copied from interface: QueryPager
      Whether or not this pager is exhausted, i.e. whether or not a call to fetchPage may return more result.
      Specified by:
      isExhausted in interface QueryPager
      Returns:
      whether the pager is exhausted.

    • maxRemaining

      public int maxRemaining()
      Description copied from interface: QueryPager
      The maximum number of cells/CQL3 row that we may still have to return. In other words, that's the initial user limit minus what we've already returned (note that it's not how many we *will* return, just the upper limit on it).
      Specified by:
      maxRemaining in interface QueryPager

    • remainingInPartition

      protected int remainingInPartition()