com.helger.commons.scope.singleton

Class AbstractRequestSingleton

java.lang.Object

com.helger.commons.scope.singleton.AbstractSingleton

com.helger.commons.scope.singleton.AbstractRequestSingleton

All Implemented Interfaces:

IScopeDestructionAware

Direct Known Subclasses:

AbstractRequestSingletonTreeWithUniqueID

public abstract class AbstractRequestSingleton
extends AbstractSingleton

This is the base class for singleton objects that reside in the request scope. This class can be used for web scopes and non-web scopes as it handled in the same object.

Author:

Philip Helger

See Also:

EScope.REQUEST

Field Summary

Fields inherited from class com.helger.commons.scope.singleton.AbstractSingleton

m_aRWLock

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	AbstractRequestSingleton()

Method Summary

Modifier and Type	Method and Description
static ICommonsList<AbstractRequestSingleton>	getAllRequestSingletons() Get all instantiated singleton objects registered in the current request scope.
static <T extends AbstractRequestSingleton> T	getRequestSingleton(Class<T> aClass) Get the singleton object in the current request scope, using the passed class.
static <T extends AbstractRequestSingleton> T	getRequestSingletonIfInstantiated(Class<T> aClass) Get the singleton object if it is already instantiated inside the current request scope or null if it is not instantiated.
static boolean	isRequestSingletonInstantiated(Class<? extends AbstractRequestSingleton> aClass) Check if a singleton is already instantiated inside the current request scope

Methods inherited from class com.helger.commons.scope.singleton.AbstractSingleton

getAllSingletons, getSingleton, getSingletonIfInstantiated, getSingletonScopeKey, isDestroyed, isInDestruction, isInInstantiation, isInPreDestruction, isInstantiated, isSingletonInstantiated, isUsableObject, onAfterInstantiation, onBeforeDestroy, onBeforeScopeDestruction, onDestroy, onScopeDestruction, readAbstractSingletonFields, setDestroyed, setInDestruction, setInInstantiation, setInPreDestruction, setInstantiated, toString, writeAbstractSingletonFields

Methods inherited from class java.lang.Object

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

Constructor Detail

AbstractRequestSingleton

protected AbstractRequestSingleton()

Method Detail

getRequestSingleton

@Nonnull
public static final <T extends AbstractRequestSingleton> T getRequestSingleton(@Nonnull
                                                                                         Class<T> aClass)

Get the singleton object in the current request scope, using the passed class. If the singleton is not yet instantiated, a new instance is created.

Type Parameters:

T - The type to be returned

Parameters:

aClass - The class to be used. May not be null. The class must be public as needs to have a public no-argument constructor.

Returns:

The singleton object and never null.

getRequestSingletonIfInstantiated

@Nullable
public static final <T extends AbstractRequestSingleton> T getRequestSingletonIfInstantiated(@Nonnull
                                                                                                        Class<T> aClass)

Get the singleton object if it is already instantiated inside the current request scope or null if it is not instantiated.

Type Parameters:

T - The type to be returned

Parameters:

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

Returns:

The singleton for the specified class is already instantiated, null otherwise.

isRequestSingletonInstantiated

public static final boolean isRequestSingletonInstantiated(@Nonnull
                                                           Class<? extends AbstractRequestSingleton> aClass)

Check if a singleton is already instantiated inside the current request scope

Parameters:

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

Returns:

true if the singleton for the specified class is already instantiated, false otherwise.

getAllRequestSingletons

@Nonnull
 @ReturnsMutableCopy
public static final ICommonsList<AbstractRequestSingleton> getAllRequestSingletons()

Get all instantiated singleton objects registered in the current request scope.

Returns:

A non-null list with all instances of this class in the current request scope.