com.helger.commons.scope.singleton

Class AbstractSessionSingleton

java.lang.Object

com.helger.commons.scope.singleton.AbstractSingleton

com.helger.commons.scope.singleton.AbstractSessionSingleton

All Implemented Interfaces:

IScopeDestructionAware, Serializable

Direct Known Subclasses:

AbstractSessionSingletonTreeWithUniqueID

@MustImplementEqualsAndHashcode
public abstract class AbstractSessionSingleton
extends AbstractSingleton
implements Serializable

This is the base class for singleton objects that reside in the session non-web scope.

Author:

Philip Helger

See Also:

EScope.SESSION, Serialized Form

Field Summary

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

m_aRWLock

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	AbstractSessionSingleton()

Method Summary

Modifier and Type	Method and Description
static List<AbstractSessionSingleton>	getAllSessionSingletons() Get all instantiated singleton objects registered in the current session scope.
static <T extends AbstractSessionSingleton> T	getSessionSingleton(Class<T> aClass) Get the singleton object in the current session scope, using the passed class.
static <T extends AbstractSessionSingleton> T	getSessionSingletonIfInstantiated(Class<T> aClass) Get the singleton object if it is already instantiated inside the current session scope or null if it is not instantiated.
static boolean	isSessionSingletonInstantiated(Class<? extends AbstractSessionSingleton> aClass) Check if a singleton is already instantiated inside the current session 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

AbstractSessionSingleton

protected AbstractSessionSingleton()

Method Detail

getSessionSingleton

@Nonnull
public static final <T extends AbstractSessionSingleton> T getSessionSingleton(@Nonnull
                                                                                         Class<T> aClass)

Get the singleton object in the current session 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.

getSessionSingletonIfInstantiated

@Nullable
public static final <T extends AbstractSessionSingleton> T getSessionSingletonIfInstantiated(@Nonnull
                                                                                                        Class<T> aClass)

Get the singleton object if it is already instantiated inside the current session 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.

isSessionSingletonInstantiated

public static final boolean isSessionSingletonInstantiated(@Nonnull
                                                           Class<? extends AbstractSessionSingleton> aClass)

Check if a singleton is already instantiated inside the current session 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.

getAllSessionSingletons

@Nonnull
 @ReturnsMutableCopy
public static final List<AbstractSessionSingleton> getAllSessionSingletons()

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

Returns:

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