Package com.helger.commons.cache

Class AnnotationUsageCache

java.lang.Object

com.helger.commons.cache.AnnotationUsageCache

@NotThreadSafe
public class AnnotationUsageCache
extends Object

A simple cache for the usage of a certain annotation class at other classes.
Note: cannot use Cache because it would need a Class<?> as a key and this would be a hard wired reference.
Since 10.1.3 the class is no longer read-write-locked, as the performance overhead is too big for reading only, compared to the penalty of double annotation determination.

Author:

Philip Helger

Constructor Summary

Constructors

Constructor	Description
AnnotationUsageCache(Class<? extends Annotation> aAnnotationClass)	Constructor

Method Summary

Modifier and Type	Method	Description
void	clearCache()	Remove all entries from the cache.
Class<? extends Annotation>	getAnnotationClass()
boolean	hasAnnotation(Class<?> aClass)	Check if the provided class has the annotation from the constructor or not.
boolean	hasAnnotation(Object aObject)	Check if the class of the passed object has the annotation provided in the constructor.
void	setAnnotation(Class<?> aClass, boolean bHasAnnotation)	In case the knowledge was gathered on the outside, remember the wisdom in this class.
String	toString()

Methods inherited from class java.lang.Object

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

Constructor Detail

AnnotationUsageCache

public AnnotationUsageCache(@Nonnull
                            Class<? extends Annotation> aAnnotationClass)

Constructor

Parameters:

aAnnotationClass - The annotation class to store the existence of. It must have the RetentionPolicy.RUNTIME to be usable within this class!

Method Detail

getAnnotationClass

@Nonnull
public final Class<? extends Annotation> getAnnotationClass()

Returns:

The annotation class passed in the constructor. Never null.

hasAnnotation

public boolean hasAnnotation(@Nonnull
                             Object aObject)

Check if the class of the passed object has the annotation provided in the constructor.

Parameters:

aObject - The object. To be checked. May not be null.

Returns:

true if the owning class has the annotation, false if not.

See Also:

hasAnnotation(Class)

hasAnnotation

public boolean hasAnnotation(@Nonnull
                             Class<?> aClass)

Check if the provided class has the annotation from the constructor or not. If the value is not yet in the cache, it will be determined.

Parameters:

aClass - The class to check. May not be null.

Returns:

true if the provided class has the annotation, false if not.

setAnnotation

public void setAnnotation(@Nonnull
                          Class<?> aClass,
                          boolean bHasAnnotation)

In case the knowledge was gathered on the outside, remember the wisdom in this class.

Parameters:

aClass - The class that it is about.

bHasAnnotation - true to indicate the presence, false to

clearCache

public void clearCache()

Remove all entries from the cache. That is mainly of interested for testing purposes, to provide a clean state.

toString

public String toString()

Overrides:

toString in class Object