org.eigenbase.sql.type
Class FamilyOperandTypeChecker

java.lang.Object
  extended by org.eigenbase.sql.type.FamilyOperandTypeChecker
All Implemented Interfaces:
SqlOperandTypeChecker, SqlSingleOperandTypeChecker

public class FamilyOperandTypeChecker
extends Object
implements SqlSingleOperandTypeChecker

Operand type-checking strategy which checks operands for inclusion in type families.

Version:
$Id: //open/dev/farrago/src/org/eigenbase/sql/type/FamilyOperandTypeChecker.java#8 $
Author:
John V. Sichi

Field Summary
protected  SqlTypeFamily[] families
           
 
Constructor Summary
FamilyOperandTypeChecker(SqlTypeFamily... families)
           
 
Method Summary
 boolean checkOperandTypes(SqlCallBinding callBinding, boolean throwOnFailure)
          Checks the types of all operands to an operator call.
 boolean checkSingleOperandType(SqlCallBinding callBinding, SqlNode node, int iFormalOperand, boolean throwOnFailure)
          Checks the type of a single operand against a particular ordinal position within a formal operator signature.
 String getAllowedSignatures(SqlOperator op, String opName)
          Returns a string describing the allowed formal signatures of a call, e.g.
 SqlTypeFamily[] getFamilies()
           
 SqlOperandCountRange getOperandCountRange()
           
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Field Detail

families

protected SqlTypeFamily[] families
Constructor Detail

FamilyOperandTypeChecker

public FamilyOperandTypeChecker(SqlTypeFamily... families)
Method Detail

checkSingleOperandType

public boolean checkSingleOperandType(SqlCallBinding callBinding,
                                      SqlNode node,
                                      int iFormalOperand,
                                      boolean throwOnFailure)
Description copied from interface: SqlSingleOperandTypeChecker
Checks the type of a single operand against a particular ordinal position within a formal operator signature. Note that the actual ordinal position of the operand being checked may be different from the position of the formal operand.

For example, when validating the actual call

C(X, Y, Z)
the strategy for validating the operand Z might involve checking its type against the formal signature OP(W). In this case, iFormalOperand would be zero, even though the position of Z within call C is two.

Specified by:
checkSingleOperandType in interface SqlSingleOperandTypeChecker
Parameters:
callBinding - description of the call being checked; this is only provided for context when throwing an exception; the implementation should NOT examine the operands of the call as part of the check
node - the actual operand to be checked
iFormalOperand - the 0-based formal operand ordinal
throwOnFailure - whether to throw an exception if check fails (otherwise returns false in that case)
Returns:
whether check succeeded

checkOperandTypes

public boolean checkOperandTypes(SqlCallBinding callBinding,
                                 boolean throwOnFailure)
Description copied from interface: SqlOperandTypeChecker
Checks the types of all operands to an operator call.

Specified by:
checkOperandTypes in interface SqlOperandTypeChecker
Parameters:
callBinding - description of the call to be checked
throwOnFailure - whether to throw an exception if check fails (otherwise returns false in that case)
Returns:
whether check succeeded

getOperandCountRange

public SqlOperandCountRange getOperandCountRange()
Specified by:
getOperandCountRange in interface SqlOperandTypeChecker
Returns:
range of operand counts allowed in a call

getAllowedSignatures

public String getAllowedSignatures(SqlOperator op,
                                   String opName)
Description copied from interface: SqlOperandTypeChecker
Returns a string describing the allowed formal signatures of a call, e.g. "SUBSTR(VARCHAR, INTEGER, INTEGER)".

Specified by:
getAllowedSignatures in interface SqlOperandTypeChecker
Parameters:
op - the operator being checked
opName - name to use for the operator in case of aliasing
Returns:
generated string

getFamilies

public SqlTypeFamily[] getFamilies()