Interface IWildcardExpressionComparator

public interface IWildcardExpressionComparator
{
  // Methods
  int compareSubexpressions (WildcardExpression expr1,
        int exprnum1, WildcardExpression expr2, int exprnum2, int
        cmpresult);
  void deleteSubexpression (WildcardExpression expr, int exprnum);
  void intersectSubexpressions (WildcardExpression expr1,
        int exprnum1, WildcardExpression expr2, int exprnum2, int
        cmpresult);
}

This interface is used to compare subexpressions in WildcardExpression.compare.

Methods

compareSubexpressions

int compareSubexpressions (WildcardExpression expr1, int exprnum1,
        WildcardExpression expr2, int exprnum2, int cmpresult);

Compares two subexpressions of different expressions.

Return Value:

Returns a SetComparison result code that is valid with WildcardExpression. This can be one of the following:

• EQUAL
• DISJOINT
• SUBSET
• OVERLAP
• SUPERSET

Parameter	Description
expr1	The first expression operand.
exprnum1	The subexpression of expr1 to compare.
expr2	The second expression operand.
exprnum2	The subexpression of expr2 to compare.
cmpresult	The result of comparing the given subexpressions (a SetComparison result code). The cmpresult value must be computed before calling this function. The subexpressions are compared, and passed to this method as cmpresult. The return value of compareSubexpressions is possibly completely independent of cmpresult. The return value is the result of comparing any extra elements that clients of WildcardExpression may have associated with each subexpression.

deleteSubexpression

void deleteSubexpression (WildcardExpression expr, int exprnum);

Called by condense when redundant expressions need to be deleted.

Return Value:

No return value.

Parameter	Description
expr	The expression from which to delete the subexpression.
exprnum	The expression number, which is the original expression index, before any deletions have occurred. The new expression numbers will take effect after condense has completed.

intersectSubexpressions

void intersectSubexpressions (WildcardExpression expr1, int exprnum1,
        WildcardExpression expr2, int exprnum2, int cmpresult);

Called by WildcardExpression.intersect to find the intersection of any data associated with two subexpressions. The resulting data should be retained for the final intersected expression.

Return Value:

No return value.

Parameter	Description
expr1	The first expression operand.
exprnum1	The subexpression of expr1 to compare.
expr2	The second expression operand.
exprnum2	The subexpression of expr2 to compare.
cmpresult	The result of comparing the given subexpressions.