org.nakedobjects.applib.spec
Class AbstractSpecification<T>

java.lang.Object
  org.nakedobjects.applib.spec.AbstractSpecification<T>

All Implemented Interfaces:

Specification

public abstract class AbstractSpecification<T>
extends java.lang.Object
implements Specification

Adapter to make it easy to write Specifications.

Provides two main features:

• first, is type-safe (with invalid type being either ignored or constituting a failure), and
• second, checks for nulls (with a null either being ignore or again constituting a failure)

Implementation note: inspired by (borrowed code from) Hamcrest's TypeSafeMatcher.

Nested Class Summary

static class	AbstractSpecification.Nullability
static class	AbstractSpecification.TypeChecking

Constructor Summary

protected	AbstractSpecification()
protected	AbstractSpecification(AbstractSpecification.Nullability nullability, AbstractSpecification.TypeChecking typeChecking)

Method Summary

java.lang.String	satisfies(java.lang.Object obj) Checks not null and is correct type, and delegates to satisfiesSafely(Object).
abstract java.lang.String	satisfiesSafely(T obj) If null then satisfied, otherwise is reason why the specification is not satisfied.

Methods inherited from class java.lang.Object

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

Constructor Detail

AbstractSpecification

protected AbstractSpecification()

AbstractSpecification

protected AbstractSpecification(AbstractSpecification.Nullability nullability,
                                AbstractSpecification.TypeChecking typeChecking)

Method Detail

satisfies

public final java.lang.String satisfies(java.lang.Object obj)

Checks not null and is correct type, and delegates to satisfiesSafely(Object).

Specified by:

satisfies in interface Specification

satisfiesSafely

public abstract java.lang.String satisfiesSafely(T obj)

If null then satisfied, otherwise is reason why the specification is not satisfied.

Subclasses should implement this. The item will already have been checked for the specific type and will never be null.