com.helger.commons.scopes.singleton

Class GlobalSingleton

java.lang.Object

com.helger.commons.scopes.AbstractSingleton

com.helger.commons.scopes.singleton.GlobalSingleton

All Implemented Interfaces:

IScopeDestructionAware

Direct Known Subclasses:

GlobalSingletonTreeWithUniqueID, ScopedFileMonitorManager, ScopeSessionManager

public abstract class GlobalSingleton
extends AbstractSingleton

This is the base class for singleton objects that reside in the global scope. The global scope is identical for web scope and non-web scope applications.

Author:

Philip Helger

See Also:

EScope.GLOBAL

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	GlobalSingleton()

Method Summary

Methods

Modifier and Type	Method and Description
static List<GlobalSingleton>	getAllGlobalSingletons() Get all instantiated singleton objects registered in the current global scope.
static <T extends GlobalSingleton> T	getGlobalSingleton(Class<T> aClass) Get the singleton object in the current global scope, using the passed class.
static <T extends GlobalSingleton> T	getGlobalSingletonIfInstantiated(Class<T> aClass) Get the singleton object if it is already instantiated inside the current global scope or null if it is not instantiated.
static boolean	isGlobalSingletonInstantiated(Class<? extends GlobalSingleton> aClass) Check if a singleton is already instantiated inside the current global scope

Methods inherited from class com.helger.commons.scopes.AbstractSingleton

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

Methods inherited from class java.lang.Object

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

Constructor Detail

GlobalSingleton

protected GlobalSingleton()

Method Detail

getGlobalSingleton

@Nonnull
public static final <T extends GlobalSingleton> T getGlobalSingleton(@Nonnull
                                                       Class<T> aClass)

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

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.

getGlobalSingletonIfInstantiated

@Nullable
public static final <T extends GlobalSingleton> T getGlobalSingletonIfInstantiated(@Nonnull
                                                                      Class<T> aClass)

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

Parameters:

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

Returns:

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

isGlobalSingletonInstantiated

public static final boolean isGlobalSingletonInstantiated(@Nonnull
                                    Class<? extends GlobalSingleton> aClass)

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

getAllGlobalSingletons

@Nonnull
public static final List<GlobalSingleton> getAllGlobalSingletons()

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

Returns:

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