Class Subscriber
- Direct Known Subclasses:
ResourceVariantTreeSubscriber
When queried for the SyncInfo
corresponding to a local resource using
getSyncInfo(IResource)
, the subscriber should not contact the server.
Server round trips should only occur within the refresh
method of the subscriber. Consequently,
the implementation of a subscriber must cache enough state information for a remote resource to calculate the
synchronization state without contacting the server. During a refresh, the latest remote resource state
information should be fetched and cached. For
a subscriber that supports three-way compare, the refresh should also fetch the latest base state unless this is
available by some other means (e.g. for some repository tools, the base state is persisted on disk with the
local resources).
After a refresh, the subscriber must notify any listeners of local resources whose corresponding remote resource
or base resource changed. The subscriber does not need to notify listeners when the state changes due to a local
modification since local changes are available through the IResource
delta mechanism. However,
the subscriber must
cache enough information (e.g. the local timestamp of when the file was in-sync with its corresponding remote
resource)
to determine if the file represents an outgoing change so that SyncInfo
obtained
after a delta will indicate that the file has an outgoing change. The subscriber must also notify listeners
when roots are added
or removed. For example, a subscriber for a repository provider would fire a root added event when a project
was shared
with a repository. No event is required when a root is deleted as this is available through the
IResource
delta mechanism. It is up to clients to re-query the subscriber
when the state of a resource changes locally by listening to IResource
deltas.
The remote and base states can also include the state for resources that do not exist locally (i.e outgoing deletions or incoming additions). When queried for the members of a local resource, the subscriber should include any children for which a remote exists even if the local does not.
- Since:
- 3.0
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Constructor Summary
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Method Summary
Modifier and TypeMethodDescriptionvoid
accept
(IResource[] resources, int depth, IDiffVisitor visitor) Visit any out-of-sync resources in the given resources visited to the given depth.void
accept
(ResourceTraversal[] traversals, IDiffVisitor visitor) Visit any out-of-sync resources covered by the given traversals.void
addListener
(ISubscriberChangeListener listener) Adds a listener to this team subscriber.void
collectOutOfSync
(IResource[] resources, int depth, SyncInfoSet set, IProgressMonitor monitor) Adds all out-of-sync resources (getKind() !
protected void
fireTeamResourceChange
(ISubscriberChangeEvent[] deltas) Fires a team resource change event to all registered listeners.Returns synchronization info, in the form of anIDiff
for the given resource, ornull
if there is no synchronization info because the subscriber does not apply to this resource or the resource is in-sync.abstract String
getName()
Return the name of this subscription, in a format that is suitable for display to an end user.abstract IResourceVariantComparator
Returns the comparison criteria that will be used by the sync info created by this subscriber.int
getState
(ResourceMapping mapping, int stateMask, IProgressMonitor monitor) Return the synchronization state of the given resource mapping.abstract SyncInfo
getSyncInfo
(IResource resource) Returns synchronization info for the given resource, ornull
if there is no synchronization info because the subscriber does not apply to this resource.abstract boolean
isSupervised
(IResource resource) Returnstrue
if this resource is supervised by this subscriber.abstract IResource[]
Returns all non-transient member resources of the given resource.abstract void
refresh
(IResource[] resources, int depth, IProgressMonitor monitor) Refreshes the resource hierarchy from the given resources and their children (to the specified depth) from the corresponding resources in the remote location.void
refresh
(ResourceTraversal[] traversals, IProgressMonitor monitor) Refresh the subscriber for the given traversals.void
removeListener
(ISubscriberChangeListener listener) Removes a listener previously registered with this team subscriber.abstract IResource[]
roots()
Returns the list of root resources this subscriber considers for synchronization.
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Constructor Details
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Subscriber
public Subscriber()
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Method Details
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getName
Return the name of this subscription, in a format that is suitable for display to an end user.- Returns:
- String representing the name of this subscription.
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isSupervised
Returnstrue
if this resource is supervised by this subscriber. A supervised resource is one for which this subscriber maintains the synchronization state. Supervised resources are the only resources returned whenmembers(IResource)
was invoked with the parent of the resource. Returnsfalse
in all other cases.- Parameters:
resource
- the resource being tested- Returns:
true
if this resource is supervised, andfalse
otherwise- Throws:
TeamException
- if an error occurs
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members
Returns all non-transient member resources of the given resource. The result will include entries for resources that exist either in the workspace or are implicated in an incoming change. Returns an empty list if the given resource exists neither in the workspace nor in the corresponding subscriber location, or if the given resource is transient.This is a fast operation; the repository is not contacted.
- Parameters:
resource
- the resource- Returns:
- a list of member resources
- Throws:
TeamException
- if an error occurs
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roots
Returns the list of root resources this subscriber considers for synchronization. A client should call this method first then can safely callmembers
to navigate the resources managed by this subscriber.- Returns:
- a list of resources
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getSyncInfo
Returns synchronization info for the given resource, ornull
if there is no synchronization info because the subscriber does not apply to this resource.Note that sync info may be returned for non-existing or for resources which have no corresponding remote resource.
This method will be quick. If synchronization calculation requires content from the server it must be cached when the subscriber is refreshed. A client should call refresh before calling this method to ensure that the latest information is available for computing the sync state.
The sync-info node returned by this method does not fully describe all types of changes. A more descriptive change can be obtained from the
getDiff(IResource)
method.- Parameters:
resource
- the resource of interest- Returns:
- sync info
- Throws:
TeamException
- if an error occurs- See Also:
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getResourceComparator
Returns the comparison criteria that will be used by the sync info created by this subscriber.- Returns:
- the comparator to use when computing sync states for this subscriber.
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refresh
public abstract void refresh(IResource[] resources, int depth, IProgressMonitor monitor) throws TeamException Refreshes the resource hierarchy from the given resources and their children (to the specified depth) from the corresponding resources in the remote location. Resources are ignored in the following cases:- if they do not exist either in the workspace or in the corresponding remote location
- if the given resource is not supervised by this subscriber
- if the given resource is a closed project (they are ineligible for synchronization)
Typical synchronization operations use the statuses computed by this method as the basis for determining what to do. It is possible for the actual sync status of the resource to have changed since the current local sync status was refreshed. Operations typically skip resources with stale sync information. The chances of stale information being used can be reduced by running this method (where feasible) before doing other operations. Note that this will of course affect performance.
The depth parameter controls whether refreshing is performed on just the given resource (depth=
DEPTH_ZERO
), the resource and its children (depth=DEPTH_ONE
), or recursively to the resource and all its descendents (depth=DEPTH_INFINITE
). Use depthDEPTH_ONE
, rather than depthDEPTH_ZERO
, to ensure that new members of a project or folder are detected.This method might change resources; any changes will be reported in a subsequent subscriber resource change event indicating changes to server sync status.
This method contacts the server and is therefore long-running; progress and cancellation are provided by the given progress monitor.
- Parameters:
resources
- the resourcesdepth
- valid values areDEPTH_ZERO
,DEPTH_ONE
, orDEPTH_INFINITE
monitor
- progress monitor, ornull
if progress reporting and cancellation are not desired- Throws:
TeamException
- if this method fails. Reasons include:- The server could not be contacted.
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addListener
Adds a listener to this team subscriber. Has no effect if an identical listener is already registered.Team resource change listeners are informed about state changes that affect the resources supervised by this subscriber.
- Parameters:
listener
- a team resource change listener
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removeListener
Removes a listener previously registered with this team subscriber. Has no effect if an identical listener is not registered.- Parameters:
listener
- a team resource change listener
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collectOutOfSync
public void collectOutOfSync(IResource[] resources, int depth, SyncInfoSet set, IProgressMonitor monitor) Adds all out-of-sync resources (getKind() != SyncInfo.IN_SYNC
) that occur under the given resources to the specified depth. The purpose of this method is to provide subscribers a means of optimizing the determination of all out-of-sync descendants of a set of resources.If any of the directly provided resources are not supervised by the subscriber, then they should be removed from the set. If errors occur while determining the sync info for the resources, they should be added to the set using
SyncInfoSet.addError
.- Parameters:
resources
- the root of the resource subtrees from which out-of-sync sync info should be collecteddepth
- the depth to which sync info should be collected (one ofIResource.DEPTH_ZERO
,IResource.DEPTH_ONE
, orIResource.DEPTH_INFINITE
)set
- the sync info set to which out-of-sync resources should be added (or removed). Any errors should be added to the set as well.monitor
- a progress monitor
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fireTeamResourceChange
Fires a team resource change event to all registered listeners. Only listeners registered at the time this method is called are notified. Listener notification makes use of anISafeRunnable
to ensure that client exceptions do not affect the notification to other clients. -
getDiff
Returns synchronization info, in the form of anIDiff
for the given resource, ornull
if there is no synchronization info because the subscriber does not apply to this resource or the resource is in-sync.Note that a diff may be returned for non-existing or for resources which have no corresponding remote resource.
This method will be quick. If synchronization calculation requires content from the server it must be cached when the subscriber is refreshed. A client should call refresh before calling this method to ensure that the latest information is available for computing the diff.
The diff node returned by this method describes the changes associated with the given resource in more detail than the sync-info returned by calling
getSyncInfo(IResource)
.- Parameters:
resource
- the resource of interest- Returns:
- the diff for the resource or
null
- Throws:
CoreException
- if an error occursTeamException
- if errors occur- Since:
- 3.2
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accept
Visit any out-of-sync resources covered by the given traversals. Any resources covered by the traversals are ignored in the following cases:- if they do not exist either in the workspace or in the corresponding remote location
- if the given resource is not supervised by this subscriber
- if the given resource is a closed project (they are ineligible for synchronization)
- Parameters:
traversals
- the traversals to be visitedvisitor
- the visitor- Throws:
CoreException
- if an error occursTeamException
- if errors occur- Since:
- 3.2
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accept
Visit any out-of-sync resources in the given resources visited to the given depth. Resources are ignored in the following cases:- if they do not exist either in the workspace or in the corresponding remote location
- if the given resource is not supervised by this subscriber
- if the given resource is a closed project (they are ineligible for synchronization)
- Parameters:
resources
- the root of the resource subtrees from which out-of-sync sync info should be visiteddepth
- the depth to which sync info should be collected (one ofIResource.DEPTH_ZERO
,IResource.DEPTH_ONE
, orIResource.DEPTH_INFINITE
)visitor
- the visitor- Throws:
CoreException
- if errors occur- Since:
- 3.2
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refresh
Refresh the subscriber for the given traversals. By default this method callsrefresh(IResource[], int, IProgressMonitor)
for each traversal. Any resources covered by the traversals are ignored in the following cases:- if they do not exist either in the workspace or in the corresponding remote location
- if the given resource is not supervised by this subscriber
- if the given resource is a closed project (they are ineligible for synchronization)
Subclasses may override.
- Parameters:
traversals
- the traversals to be refreshedmonitor
- a progress monitor- Throws:
TeamException
- if errors occur- Since:
- 3.2
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getState
public int getState(ResourceMapping mapping, int stateMask, IProgressMonitor monitor) throws CoreException Return the synchronization state of the given resource mapping. Only return the portion of the synchronization state that matches the providedstateMask
. The synchronization state flags that are guaranteed to be interpreted by this method are:- The kind flags
IDiff.ADD
,IDiff.REMOVE
andIDiff.CHANGE
. If none of these flags are included then all are assumed. - The direction flags
IThreeWayDiff.INCOMING
andIThreeWayDiff.OUTGOING
if the subscriber is a three-way subscriber. If neither are provided, both are assumed.
An element will only include
IDiff.ADD
in the returned state if all resources covered by the traversals mappings are added. Similarly,IDiff.REMOVE
will only be included if all the resources covered by the traversals are deleted. OtherwiseIDiff.CHANGE
will be returned.- Parameters:
mapping
- the resource mapping whose synchronization state is to be determinedstateMask
- the mask that identifies the state flags of interestedmonitor
- a progress monitor- Returns:
- the synchronization state of the given resource mapping
- Throws:
CoreException
- if an error occurs- Since:
- 3.2
- See Also:
- The kind flags
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