com.tensegrity.generic.constraint
Class EnumConstraint

java.lang.Object
  com.tensegrity.generic.constraint.AbstractConstraint
      com.tensegrity.generic.constraint.EnumConstraint

All Implemented Interfaces:

Constraint

Direct Known Subclasses:

OpenEnumConstraint

public class EnumConstraint

extends com.tensegrity.generic.constraint.AbstractConstraint

Used to check whether the value that is subject to validation is equal to one of the entries of the list of values on the right-hand-side of the operator. The entries of the list of values can be quoted strings or numbers. Interleaving both elements is allowed. The EnumConstraint validates its value by means of the potentially overridden equals() method of the value object.

Version:

$Id: EnumConstraint.java,v 1.23 2005/04/01 15:40:21 MichaelKegel Exp $

Author:

MichaelKegel

See Also:

Constraint, ConstraintParser

Field Summary

protected java.lang.String

lastError string used to trace for the last error

Method Summary

java.lang.Object[]	getAlternatives() Returns the legal alternatives of this enum constraint.
Constraint	intern() Pools this constraint analogous to the java.lang.String.intern() method.
java.lang.String	toString() Returns a string representation of this constraint.
void	trace(java.lang.StringBuffer sb) Default implementation appending the last error occured to the given StringBuffer.
boolean	validate(java.lang.Object value) Validates this contraint against a given value.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

lastError

protected java.lang.String lastError

string used to trace for the last error

Method Detail

validate

public boolean validate(java.lang.Object value)

Description copied from interface: Constraint

Validates this contraint against a given value.
Notice:The given argument may not be null.

Parameters:

value - the object to validate. It is not allowed to pass in null as an argument.

Returns:

true if this value confirms to this constraints and false if it doesn't.

getAlternatives

public java.lang.Object[] getAlternatives()

Returns the legal alternatives of this enum constraint.

Returns:

legal alternatives of the constraint.

toString

public java.lang.String toString()

Returns a string representation of this constraint.

Returns:

a string representation of this constraint.

intern

public Constraint intern()

Pools this constraint analogous to the java.lang.String.intern() method. This method is not threadsafe.

Specified by:

intern in interface Constraint

Returns:

the pooled instance of this constraint. The returned object reference is the same as the this-reference if this object has not been pooled before.

trace

public void trace(java.lang.StringBuffer sb)

Default implementation appending the last error occured to the given StringBuffer.

Specified by:

trace in interface Constraint

Parameters:

sb - the stringbuffer to append the last error to.