Class UTFQualifier

java.lang.Object
org.apache.derby.impl.store.access.UTFQualifier
All Implemented Interfaces:
Qualifier
public class UTFQualifier extends Object implements Qualifier

  • Field Details

    • value

      private UTF value

    • columnId

      private int columnId

  • Constructor Details

    • UTFQualifier

      public UTFQualifier(int columnId, String value)

  • Method Details

    • getColumnId

      public int getColumnId()
      Get the id of the column to be qualified.
      Specified by:
      getColumnId in interface Qualifier

    • getOrderable

      public DataValueDescriptor getOrderable()
      Get the value that the column is to be compared to.
      Specified by:
      getOrderable in interface Qualifier

    • getOperator

      public int getOperator()
      Get the operator to use in the comparison.
      Specified by:
      getOperator in interface Qualifier
      See Also:

    • negateCompareResult

      public boolean negateCompareResult()
      Determine if the result from the compare operation is to be negated.

      If true then only rows which fail the compare operation will qualify.

      Specified by:
      negateCompareResult in interface Qualifier
      See Also:

    • getOrderedNulls

      public boolean getOrderedNulls()
      Description copied from interface: Qualifier
      Get the getOrderedNulls argument to use in the comparison.
      Specified by:
      getOrderedNulls in interface Qualifier
      See Also:

    • getUnknownRV

      public boolean getUnknownRV()
      Get the getOrderedNulls argument to use in the comparison.
      Specified by:
      getUnknownRV in interface Qualifier
      See Also:

    • clearOrderableCache

      public void clearOrderableCache()
      Clear the DataValueDescriptor cache, if one exists. (The DataValueDescriptor can be 1 of 3 types: o VARIANT - cannot be cached as its value can vary within a scan o SCAN_INVARIANT - can be cached within a scan as its value will not change within a scan o QUERY_INVARIANT- can be cached across the life of the query as its value will never change o CONSTANT - can be cached across executions
      Specified by:
      clearOrderableCache in interface Qualifier
      See Also:

    • reinitialize

      public void reinitialize()
      This method reinitializes all the state of the Qualifier. It is used to distinguish between resetting something that is query invariant and something that is constant over every execution of a query. Basically, clearOrderableCache() will only clear out its cache if it is a VARIANT or SCAN_INVARIANT value. However, each time a query is executed, the QUERY_INVARIANT qualifiers need to be reset.
      Specified by:
      reinitialize in interface Qualifier