Class ArrayFilter

All Implemented Interfaces:
ExternalizableLite, PortableObject, Filter, EntryFilter, IndexAwareFilter, QueryRecorderFilter, Serializable
Direct Known Subclasses:
AllFilter, AnyFilter, XorFilter

Filter which is a logical operator of a filter array.
Author:
cp/gg 2002.11.01
See Also:
  • Field Details

    • m_aFilter

      protected Filter[] m_aFilter
      The Filter array.
    • m_fPreserveOrder

      protected boolean m_fPreserveOrder
      Flag indicating whether or not the filter order should be preserved.
      Since:
      Coherence 12.2.1
  • Constructor Details

    • ArrayFilter

      public ArrayFilter()
      Default constructor (necessary for the ExternalizableLite interface).
    • ArrayFilter

      public ArrayFilter(Filter[] aFilter)
      Construct a logical filter that applies a binary operator to a filter array. The result is defined as:
      aFilter[0] <op> aFilter[1] ... <op> aFilter[n]
      Parameters:
      aFilter - the filter array
  • Method Details

    • evaluateEntry

      public boolean evaluateEntry(Map.Entry entry)
      Apply the test to a Map Entry.
      Specified by:
      evaluateEntry in interface EntryFilter
      Parameters:
      entry - the Map Entry to evaluate; never null
      Returns:
      true if the test passes, false otherwise
    • applyIndex

      public Filter applyIndex(Map mapIndexes, Set setKeys)
      Filter remaining keys using a Map of available indexes.

      The filter is responsible for removing all keys from the passed set of keys that the applicable indexes can prove should be filtered. If the filter does not fully evaluate the remaining keys using just the index information, it must return a filter (which may be an EntryFilter) that can complete the task using an iterating implementation. If, on the other hand, the filter does fully evaluate the remaining keys using just the index information, then it should return null to indicate that no further filtering is necessary.

      Specified by:
      applyIndex in interface IndexAwareFilter
      Parameters:
      mapIndexes - the available MapIndex objects keyed by the related ValueExtractor; read-only
      setKeys - the mutable set of keys that remain to be filtered
      Returns:
      a Filter object (which may be an EntryFilter) that can be used to process the remaining keys, or null if no additional filter processing is necessary
    • explain

      public void explain(QueryContext ctx, QueryRecord.PartialResult.ExplainStep step, Set setKeys)
      Record the projected query execution cost by this filter.

      This method is expected to record the order of execution and estimated cost of applying corresponding indexes in the given step without actually applying any indexes or evaluating entries.

      Specified by:
      explain in interface QueryRecorderFilter
      Parameters:
      ctx - the query context
      step - the step used to record the estimated execution cost
      setKeys - the set of keys that would be filtered
    • trace

      public Filter trace(QueryContext ctx, QueryRecord.PartialResult.TraceStep step, Set setKeys)
      Filter the given keys using available indexes and record the cost of execution on the given step of the QueryRecord.

      This method should record the size of the given key set before and after applying corresponding indexes using QueryRecord.PartialResult.RecordableStep.recordPreFilterKeys(int) and QueryRecord.PartialResult.TraceStep.recordPostFilterKeys(int) as well as the corresponding execution time using the QueryRecord.PartialResult.TraceStep.recordDuration(long) method.

      This method is only called if the filter is an IndexAwareFilter and its implementations should explicitly call applyIndex() to actually perform the query. Additionally, this method should return the filter object (if any) returned by the applyIndex() call.

      Specified by:
      trace in interface QueryRecorderFilter
      Parameters:
      ctx - the query context
      step - the step used to record the execution cost
      setKeys - the mutable set of keys that remain to be filtered
      Returns:
      the filter returned from IndexAwareFilter.applyIndex(Map, Set)
    • trace

      public boolean trace(QueryContext ctx, QueryRecord.PartialResult.TraceStep step, Map.Entry entry)
      Evaluate the specified entry against this filter and record the evaluation cost on the given step of the QueryRecord.

      This method should record the corresponding latencies using QueryRecord.PartialResult.TraceStep.recordDuration(long).

      Implementations are responsible for explicitly calling evaluateEntry() method to perform the actual entry evaluation. Additionally, this method should return the result of the evaluateEntry call.

      Specified by:
      trace in interface QueryRecorderFilter
      Parameters:
      ctx - the context
      step - the step used to record the evaluation cost
      entry - the entry to evaluate
      Returns:
      the result returned from EntryFilter.evaluateEntry(Map.Entry)
    • applyIndex

      protected abstract Filter applyIndex(Map mapIndexes, Set setKeys, QueryContext ctx, QueryRecord.PartialResult.TraceStep step)
      Apply the specified IndexAwareFilter to the specified keySet. Record the actual cost of execution for each of the participating filters if a query context is provided.
      Parameters:
      mapIndexes - the available MapIndex objects keyed by the related ValueExtractor; read-only
      setKeys - the set of keys that would be filtered
      ctx - the query ctx; may be null
      step - the step used to record the execution cost
      Returns:
      a Filter object that can be used to process the remaining keys, or null if no additional filter processing is necessary
    • evaluateEntry

      protected abstract boolean evaluateEntry(Map.Entry entry, QueryContext ctx, QueryRecord.PartialResult.TraceStep step)
      Check if the given entry passes the filter's evaluation. Record the actual cost of execution for each of the participating filters if a query context is provided.
      Parameters:
      entry - a key value pair to filter
      ctx - the query ctx; may be null
      step - the step used to record the execution cost
      Returns:
      true if the entry passes the filter, false otherwise
    • getFilters

      public Filter[] getFilters()
      Obtain the Filter array.
      Returns:
      the Filter array
    • honorOrder

      public void honorOrder()
      Ensure that the order of underlying filters is preserved by the applyIndex(java.util.Map, java.util.Set) and evaluateEntry(java.util.Map.Entry) implementations.
    • optimizeFilterOrder

      protected void optimizeFilterOrder(Map mapIndexes, Set setKeys)
      Sort all the participating filters according to their effectiveness.
      Parameters:
      mapIndexes - the available MapIndex objects keyed by the related ValueExtractor; read-only
      setKeys - the set of keys that will be filtered; read-only
    • applyFilter

      protected Filter applyFilter(Filter filter, int iFilter, Map mapIndexes, Set setKeys, QueryContext ctx, QueryRecord.PartialResult.TraceStep step)
      Apply the specified IndexAwareFilter to the specified keySet. Record the actual cost of execution if a query context is provided.
      Parameters:
      filter - the IndexAwareFilter to apply an index to
      iFilter - the index of the given filter in this filter's array of indexes
      mapIndexes - the available MapIndex objects keyed by the related ValueExtractor; read-only
      setKeys - the mutable set of keys that remain to be filtered
      ctx - the query ctx; may be null
      step - the step used to record the execution cost
      Returns:
      a Filter object that can be used to process the remaining keys, or null if no additional filter processing is necessary
    • evaluateFilter

      protected boolean evaluateFilter(Filter filter, Map.Entry entry, QueryContext ctx, QueryRecord.PartialResult.TraceStep step)
      Check if the given entry passes the given filter's evaluation. Record the actual cost of execution if a query context is provided.
      Parameters:
      filter - the Filter to use to evaluate the entry
      entry - a key value pair to filter
      ctx - the query ctx; may be null
      step - the step used to record the execution cost
      Returns:
      true if the entry passes the filter, false otherwise
    • equals

      public boolean equals(Object o)
      Compare the ArrayFilter with another object to determine equality. Two ArrayFilter objects are considered equal iff they belong to exactly the same class and their filter arrays are equal.
      Overrides:
      equals in class Object
      Returns:
      true iff this ArrayFilter and the passed object are equivalent ArrayFilters
    • hashCode

      public int hashCode()
      Determine a hash value for the ArrayFilter object according to the general Object.hashCode() contract.
      Overrides:
      hashCode in class Object
      Returns:
      an integer hash value for this ArrayFilter object
    • toString

      public String toString()
      Return a human-readable description for this Filter.
      Overrides:
      toString in class Object
      Returns:
      a String description of the Filter
    • readExternal

      public void readExternal(DataInput in) throws IOException
      Restore the contents of this object by loading the object's state from the passed DataInput object.
      Specified by:
      readExternal in interface ExternalizableLite
      Parameters:
      in - the DataInput stream to read data from in order to restore the state of this object
      Throws:
      IOException - if an I/O exception occurs
    • writeExternal

      public void writeExternal(DataOutput out) throws IOException
      Save the contents of this object by storing the object's state into the passed DataOutput object.
      Specified by:
      writeExternal in interface ExternalizableLite
      Parameters:
      out - the DataOutput stream to write the state of this object to
      Throws:
      IOException - if an I/O exception occurs
    • readExternal

      public void readExternal(PofReader in) throws IOException
      Restore the contents of a user type instance by reading its state using the specified PofReader object.
      Specified by:
      readExternal in interface PortableObject
      Parameters:
      in - the PofReader from which to read the object's state
      Throws:
      IOException - if an I/O error occurs
    • writeExternal

      public void writeExternal(PofWriter out) throws IOException
      Save the contents of a POF user type instance by writing its state using the specified PofWriter object.
      Specified by:
      writeExternal in interface PortableObject
      Parameters:
      out - the PofWriter to which to write the object's state
      Throws:
      IOException - if an I/O error occurs