Package com.yahoo.jdisc

Interface SharedResource

All Known Subinterfaces:

ClientProvider, Container, DelegatedRequestHandler, RequestHandler, ServerProvider

All Known Implementing Classes:

AbstractClientProvider, AbstractRequestHandler, AbstractResource, AbstractServerProvider, ActiveContainer, NonWorkingClientProvider, NonWorkingRequestHandler, NonWorkingServerProvider, NoopSharedResource, Request, ResourcePool, ThreadedRequestHandler

public interface SharedResource

This interface defines a reference counted resource. This is the parent interface of RequestHandler, ClientProvider and ServerProvider, and is used by jDISC to appropriately signal resources as they become candidates for deallocation. As a ContainerBuilder is activated, all its components are retained by that Container. Once a DeactivatedContainer terminates, all of that Container's components are released. This resource tracking allows an Application to implement a significantly simpler scheme for managing its resources than would otherwise be possible.

Objects are created with an initial reference count of 1, representing the reference held by the object creator.

You should not really think about the management of resources in terms of reference counting, instead think of it in terms of resource ownership. You retain a resource to prevent it from being destroyed while you are using it, and you release a resource once you are done using it.

Author:

Simon Thoresen Hult

Nested Class Summary

Nested Classes

Modifier and Type	Interface	Description
static class	SharedResource.Debug

Field Summary

Fields

Modifier and Type	Field	Description
static SharedResource.Debug	DEBUG
static String	SYSTEM_PROPERTY_NAME_DEBUG

Method Summary

Modifier and Type	Method	Description
default ResourceReference	refer()	Creates a reference to this resource.
default ResourceReference	refer(Object context)	Creates a reference to this resource.
void	release()	Releases the "main" reference to this resource (the implicit reference due to creation of the object).

Field Detail

SYSTEM_PROPERTY_NAME_DEBUG

static final String SYSTEM_PROPERTY_NAME_DEBUG

See Also:

Constant Field Values

DEBUG

static final SharedResource.Debug DEBUG

Method Detail

refer

default ResourceReference refer()

Creates a reference to this resource. You call this method to prevent an object from being destroyed until you have finished using it.

You MUST keep the returned ResourceReference object and release the reference by calling ResourceReference.close() on it. A reference created by this method can NOT be released by calling release().

See Also:

ResourceReference.close()

refer

default ResourceReference refer(Object context)

Creates a reference to this resource. You call this method to prevent an object from being destroyed until you have finished using it. You can attach a context that will live as long as the reference.

Parameters:

context - A context to be associated with the reference. It should give some clue as to who referenced it.

You MUST keep the returned ResourceReference object and release the reference by calling ResourceReference.close() on it. A reference created by this method can NOT be released by calling release().

See Also:

ResourceReference.close()

release

void release()

Releases the "main" reference to this resource (the implicit reference due to creation of the object).

References obtained by calling refer() must be released by calling ResourceReference.close() on the ResourceReference returned from refer(), NOT by calling this method. You call this method once you are done using an object that you have previously caused instantiation of.

See Also:

ResourceReference