Package org.springframework.expression

Interface OperatorOverloader

All Known Implementing Classes:

StandardOperatorOverloader

public interface OperatorOverloader

By default, the mathematical operators defined in Operation support simple types like numbers. By providing an implementation of OperatorOverloader, a user of the expression language can support these operations on other types.

Since:

3.0

Author:

Andy Clement

Method Summary

Modifier and Type	Method	Description
Object	operate(Operation operation, @Nullable Object leftOperand, @Nullable Object rightOperand)	Perform the specified operation on the two operands, returning a result.
boolean	overridesOperation(Operation operation, @Nullable Object leftOperand, @Nullable Object rightOperand)	Return true if this operator overloader supports the specified operation on the two operands and should be invoked to handle it.

Method Details

overridesOperation

boolean overridesOperation(Operation operation,
 @Nullable Object leftOperand,
 @Nullable Object rightOperand)
                    throws EvaluationException

Return true if this operator overloader supports the specified operation on the two operands and should be invoked to handle it.

Parameters:

operation - the operation to be performed

leftOperand - the left operand

rightOperand - the right operand

Returns:

true if this OperatorOverloader supports the specified operation between the two operands

Throws:

EvaluationException - if there is a problem performing the operation

operate

Object operate(Operation operation,
 @Nullable Object leftOperand,
 @Nullable Object rightOperand)
        throws EvaluationException

Perform the specified operation on the two operands, returning a result.

See Operation for supported operations.

Parameters:

operation - the operation to be performed

leftOperand - the left operand

rightOperand - the right operand

Returns:

the result of performing the operation on the two operands

Throws:

EvaluationException - if there is a problem performing the operation