If the value property of this instance is not already set,
this method dynamically finds the method with the specified
methodName on this target with these arguments and calls it.
The result of the method invocation is first copied
into the value property of this expression and then returned
as the result of
getValue
. If the value property
was already set, either by a call to
setValue
or a previous call to
getValue
then the value
property is returned without either looking up or calling the method.
The value property of an Expression
is set to
a unique private (non-null
) value by default and
this value is used as an internal indication that the method
has not yet been called. A return value of null
replaces this default value in the same way that any other value
would, ensuring that expressions are never evaluated more than once.
See the excecute
method for details on how
methods are chosen using the dynamic types of the target
and arguments.
Returns:
The result of applying this method to these arguments.
See Also:
Statement.execute()
,
Expression.setValue(java.lang.Object)
,