Package org.h2.result

Class SortOrder

java.lang.Object
org.h2.result.SortOrder
All Implemented Interfaces:
Comparator<Value[]>
public final class SortOrder extends Object implements Comparator<Value[]>
A sort order represents an ORDER BY clause in a query.

  • Field Details

    • ASCENDING

      public static final int ASCENDING
      This bit mask means the values should be sorted in ascending order.
      See Also:

    • DESCENDING

      public static final int DESCENDING
      This bit mask means the values should be sorted in descending order.
      See Also:

    • NULLS_FIRST

      public static final int NULLS_FIRST
      This bit mask means NULLs should be sorted before other data, no matter if ascending or descending order is used.
      See Also:

    • NULLS_LAST

      public static final int NULLS_LAST
      This bit mask means NULLs should be sorted after other data, no matter if ascending or descending order is used.
      See Also:

  • Constructor Details

    • SortOrder

      public SortOrder(SessionLocal session, int[] queryColumnIndexes)
      Construct a new sort order object with default sort directions.
      Parameters:
      session - the session
      queryColumnIndexes - the column index list

    • SortOrder

      public SortOrder(SessionLocal session, int[] queryColumnIndexes, int[] sortType, ArrayList<QueryOrderBy> orderList)
      Construct a new sort order object.
      Parameters:
      session - the session
      queryColumnIndexes - the column index list
      sortType - the sort order bit masks
      orderList - the original query order list (if this is a query)

  • Method Details

    • getSQL

      public StringBuilder getSQL(StringBuilder builder, Expression[] list, int visible, int sqlFlags)
      Create the SQL snippet that describes this sort order. This is the SQL snippet that usually appears after the ORDER BY clause.
      Parameters:
      builder - string builder to append to
      list - the expression list
      visible - the number of columns in the select list
      sqlFlags - formatting flags
      Returns:
      the specified string builder

    • typeToString

      public static void typeToString(StringBuilder builder, int type)
      Appends type information (DESC, NULLS FIRST, NULLS LAST) to the specified statement builder.
      Parameters:
      builder - string builder
      type - sort type

    • compare

      public int compare(Value[] a, Value[] b)
      Compare two expression lists.
      Specified by:
      compare in interface Comparator<Value[]>
      Parameters:
      a - the first expression list
      b - the second expression list
      Returns:
      the result of the comparison

    • compare

      public int compare(Value[] a, Value[] b, int count)
      Compare two expression lists.
      Parameters:
      a - the first expression list
      b - the second expression list
      count - number of columns to compare
      Returns:
      the result of the comparison

    • sort

      public void sort(ArrayList<Value[]> rows)
      Sort a list of rows.
      Parameters:
      rows - the list of rows

    • sort

      public void sort(ArrayList<Value[]> rows, int fromInclusive, int toExclusive)
      Sort a list of rows using offset and limit.
      Parameters:
      rows - the list of rows
      fromInclusive - the start index, inclusive
      toExclusive - the end index, exclusive

    • getQueryColumnIndexes

      public int[] getQueryColumnIndexes()
      Get the column index list. This is the column indexes of the order by expressions within the query.

      For the query "select name, id from test order by id, name" this is {1, 0} as the first order by expression (the column "id") is the second column of the query, and the second order by expression ("name") is the first column of the query.

      Returns:
      the list

    • getColumn

      public Column getColumn(int index, TableFilter filter)
      Get the column for the given table filter, if the sort column is for this filter.
      Parameters:
      index - the column index (0, 1,..)
      filter - the table filter
      Returns:
      the column, or null

    • getSortTypes

      public int[] getSortTypes()
      Get the sort order bit masks.
      Returns:
      the list

    • getOrderList

      public ArrayList<QueryOrderBy> getOrderList()
      Returns the original query order list.
      Returns:
      the original query order list

    • getSortTypesWithNullOrdering

      public int[] getSortTypesWithNullOrdering()
      Returns sort order bit masks with NULLS_FIRST or NULLS_LAST explicitly set.
      Returns:
      bit masks with either NULLS_FIRST or NULLS_LAST explicitly set.

    • addNullOrdering

      public static int[] addNullOrdering(Database database, int[] sortTypes)
      Add explicit NULLS_FIRST or NULLS_LAST where they aren't already specified.
      Parameters:
      database - the database
      sortTypes - bit masks
      Returns:
      the specified array with possibly modified bit masks

    • inverse

      public static int inverse(int sortTypeWithNull)

    • getRowValueComparator

      public Comparator<Value> getRowValueComparator()
      Returns comparator for row values.
      Returns:
      comparator for row values.