org.grouplens.grapht.reflect

Class Qualifiers

java.lang.Object

org.grouplens.grapht.reflect.Qualifiers

public final class Qualifiers
extends Object

Utilities related to Qualifier implementations.

Author:

GroupLens Research

Method Summary

Modifier and Type	Method and Description
static boolean	isQualifier(Class<? extends Annotation> type) Return true or false whether or not the annotation type represents a Qualifier
static QualifierMatcher	match(Annotation annot)
static QualifierMatcher	match(Class<? extends Annotation> annotType)
static QualifierMatcher	matchAny()
static QualifierMatcher	matchDefault() The default qualifier matcher.
static QualifierMatcher	matchNone()
static Class<? extends Annotation>	resolveAliases(Class<? extends Annotation> type) Resolve qualifier aliases, returning the target qualifier.

Methods inherited from class java.lang.Object

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

Method Detail

isQualifier

public static boolean isQualifier(Class<? extends Annotation> type)

Return true or false whether or not the annotation type represents a Qualifier

Parameters:

type - The annotation type

Returns:

True if the annotation is a Qualifier or parameter

Throws:

NullPointerException - if the type is null

resolveAliases

@Nonnull
public static Class<? extends Annotation> resolveAliases(@Nonnull
                                                                   Class<? extends Annotation> type)

Resolve qualifier aliases, returning the target qualifier. Aliases are resolved recursively.

Parameters:

type - The annotation type.

Returns:

The annotation type for which this type is an alias, or type if it is not an alias.

Throws:

IllegalArgumentException - if there is a problem with the type, such as a circular alias reference.

matchDefault

public static QualifierMatcher matchDefault()

The default qualifier matcher. This is currently the any matcher.

Returns:

A QualifierMatcher that matches using the default policy.

matchAny

public static QualifierMatcher matchAny()

Returns:

A QualifierMatcher that matches any qualifier

matchNone

public static QualifierMatcher matchNone()

Returns:

A QualifierMatcher that matches only the null qualifier

match

public static QualifierMatcher match(Class<? extends Annotation> annotType)

Parameters:

annotType - Annotation type class to match; null to match only the lack of a qualifier.

Returns:

A QualifierMatcher that matches any annotation of the given class type.

match

public static QualifierMatcher match(Annotation annot)

Parameters:

annot - Annotation instance to match, or null to match only the lack of a qualifier.

Returns:

A QualifierMatcher that matches annotations equaling annot