Class StatementMappingIndex

java.lang.Object
org.datanucleus.store.rdbms.query.StatementMappingIndex
public class StatementMappingIndex extends Object
Representation of a mapping in a statement (such as JDBC), and its mapping to the associated column(s) or parameters that the mapping relates to. The mapping may be for a field of a class (whether it is a real field or a surrogate), or for a parameter.
  • Provides index positions of the column(s) of this field in the result clause of the statement
  • Provides parameter position(s) if any of the column(s) are statement parameters, for input
For example, fields of a class in the result clause of a statement. 
CLASS                 FIELDNUM     MAPPING            TABLE                COLUMN POSITIONS
-----------------     --------     --------------     ----------------     ----------------
class A                                               TABLE_A              
{
   short fieldA;      1            ShortMapping       COL_FIELDA           1
   String fieldB;     2            StringMapping      COL_FIELDB_PART1     2
                                                      COL_FIELDB_PART2     3
   ...
}

  • Field Details

    • mapping

      JavaTypeMapping mapping
      Mapping being represented.

    • columnPositions

      int[] columnPositions
      Positions for the column(s) for this field in the result clause of a statement.

    • paramPositions

      List<int[]> paramPositions
      Positions where this mapping is a parameter. Each usage of the mapping has n parameter positions.

    • columnName

      String columnName
      Any name applied in the field selection (SELECT xxx AS yyy). Only applies for cases with 1 column.

  • Constructor Details

    • StatementMappingIndex

      public StatementMappingIndex(JavaTypeMapping mapping)

  • Method Details

    • getMapping

      public JavaTypeMapping getMapping()

    • setMapping

      public void setMapping(JavaTypeMapping mapping)

    • getColumnAlias

      public String getColumnAlias()
      Accessor for the column name alias (if any). Only applies to the first column for this field.
      Returns:
      The column alias.

    • setColumnAlias

      public void setColumnAlias(String alias)
      Mutator for the column name (alias). Overrides the name of the field that the mapping refers to.
      Parameters:
      alias - The name of the column (alias).

    • getColumnPositions

      public int[] getColumnPositions()
      Accessor for the column position(s).
      Returns:
      The column position(s) in the result clause of the statement.

    • setColumnPositions

      public void setColumnPositions(int[] pos)
      Mutator for the column positions in the result clause of a statement.
      Parameters:
      pos - The column position(s)

    • addParameterOccurrence

      public void addParameterOccurrence(int[] positions)
      Method to register statement position(s) that this mapping is used as a parameter. The number of positions must be the same as the mapping number of columns.
      Parameters:
      positions - The parameter positions in the statement.

    • removeParameterOccurrence

      public void removeParameterOccurrence(int[] positions)
      Method to deregister statement positions that this mapping is used as a parameter.
      Parameters:
      positions - The param positions to deregister

    • getNumberOfParameterOccurrences

      public int getNumberOfParameterOccurrences()
      Accessor for the number of times this mapping is used as a parameter.
      Returns:
      Number of times used as a parameter

    • getParameterPositionsForOccurrence

      public int[] getParameterPositionsForOccurrence(int num)
      Accessor for the parameter positions for this occurrence of use of the mapping as a parameter.
      Parameters:
      num - The occurrence of using this mapping as a parameter.
      Returns:
      The parameter positions

    • toString

      public String toString()
      Method to return a string version of this object.
      Overrides:
      toString in class Object
      Returns:
      String version