Class RemoteResourceMappingContext

  • Direct Known Subclasses:
    SubscriberResourceMappingContext

    public abstract class RemoteResourceMappingContext
    extends ResourceMappingContext
    A remote mapping context provides a model element with a view of the remote state of local resources as they relate to a repository operation that is in progress. A repository provider can pass an instance of this interface to a model element when obtaining a set of traversals for a model element. This allows the model element to query the remote state of a resource in order to determine if there are resources that exist remotely but do not exist locally that should be included in the traversal.

    This class may be subclassed by clients.

    Since:
    3.2
    See Also:
    ResourceMapping, ResourceMappingContext
    • Field Detail

      • FILE_CONTENTS_REQUIRED

        public static final int FILE_CONTENTS_REQUIRED
        Refresh flag constant (bit mask value 1) indicating that the mapping will be making use of the contents of the files covered by the traversals being refreshed.
        See Also:
        Constant Field Values
      • NONE

        public static final int NONE
        Refresh flag constant (bit mask value 0) indicating that no additional refresh behavior is required.
        See Also:
        Constant Field Values
    • Constructor Detail

      • RemoteResourceMappingContext

        public RemoteResourceMappingContext()
    • Method Detail

      • fetchBaseContents

        public abstract IStorage fetchBaseContents​(IFile file,
                                                   IProgressMonitor monitor)
                                            throws CoreException
        For three-way comparisons, returns an instance of IStorage in order to allow the caller to access the contents of the base resource that corresponds to the given local resource. The base of a resource is the contents of the resource before any local modifications were made. If the base file does not exist, or if this is a two-way comparison, null is returned. The provided local file handle need not exist locally. A exception is thrown if the corresponding base resource is not a file.

        This method may be long running as a server may need to be contacted to obtain the contents of the file.

        Parameters:
        file - the local file
        monitor - a progress monitor, or null if progress reporting is not desired
        Returns:
        a storage that provides access to the contents of the local resource's corresponding remote resource. If the remote file does not exist, null is returned
        Throws:
        CoreException - if the contents could not be fetched. Reasons include:
      • fetchBaseMembers

        public IResource[] fetchBaseMembers​(IContainer container,
                                            IProgressMonitor monitor)
                                     throws CoreException
        Returns the members of the base resource corresponding to the given container. The container and the returned members need not exist locally and may not include all children that exist locally. An empty list is returned if the base resource is empty or does not exist. An exception is thrown if the base resource is not capable of having members. This method returns null if the base members cannot be computed, in which case clients should call fetchMembers(IContainer, IProgressMonitor) which returns the combined members for the base and remote.

        This method may be long running as a server may need to be contacted to obtain the members of the base resource.

        This default implementation always returns null, but subclasses may override.

        Parameters:
        container - the local container
        monitor - a progress monitor, or null if progress reporting is not desired
        Returns:
        the members of the base resource corresponding to the given container
        Throws:
        CoreException - if the members could not be fetched. Reasons include:
        Since:
        3.3
      • fetchMembers

        public abstract IResource[] fetchMembers​(IContainer container,
                                                 IProgressMonitor monitor)
                                          throws CoreException
        Returns the combined members of the base and remote resources corresponding to the given container. The container need not exist locally and the result may include entries that do not exist locally and may not include all local children. An empty list is returned if the remote resource which corresponds to the container is empty or if the remote does not exist. An exception is thrown if the corresponding remote is not capable of having members.

        This method may be long running as a server may need to be contacted to obtain the members of the container's corresponding remote resource.

        Parameters:
        container - the local container
        monitor - a progress monitor, or null if progress reporting is not desired
        Returns:
        returns the combined members of the base and remote resources corresponding to the given container.
        Throws:
        CoreException - if the members could not be fetched. Reasons include:
      • fetchRemoteContents

        public abstract IStorage fetchRemoteContents​(IFile file,
                                                     IProgressMonitor monitor)
                                              throws CoreException
        Returns an instance of IStorage in order to allow the caller to access the contents of the remote that corresponds to the given local resource. If the remote file does not exist, null is returned. The provided local file handle need not exist locally. A exception is thrown if the corresponding remote resource is not a file.

        This method may be long running as a server may need to be contacted to obtain the contents of the file.

        Parameters:
        file - the local file
        monitor - a progress monitor, or null if progress reporting is not desired
        Returns:
        a storage that provides access to the contents of the local resource's corresponding remote resource. If the remote file does not exist, null is returned
        Throws:
        CoreException - if the contents could not be fetched. Reasons include:
      • fetchRemoteMembers

        public IResource[] fetchRemoteMembers​(IContainer container,
                                              IProgressMonitor monitor)
                                       throws CoreException
        Returns the members of the remote resource corresponding to the given container. The container and the returned members need not exist locally and may not include all children that exist locally. An empty list is returned if the remote resource is empty or does not exist. An exception is thrown if the remote resource is not capable of having members. This method returns null if the remote members cannot be computed, in which case clients should call fetchMembers(IContainer, IProgressMonitor) which returns the combined members for the base and remote.

        This method may be long running as a server may need to be contacted to obtain the members of the remote resource.

        This default implementation always returns null, but subclasses may override.

        Parameters:
        container - the local container
        monitor - a progress monitor, or null if progress reporting is not desired
        Returns:
        the members of the remote resource corresponding to the given container
        Throws:
        CoreException - if the members could not be fetched. Reasons include:
        Since:
        3.3
      • getProjects

        public abstract IProject[] getProjects()
        Return the list of projects that apply to this context. In other words, the context is only capable of querying the remote state for projects that are contained in the returned list.
        Returns:
        the list of projects that apply to this context
      • hasLocalChange

        public abstract boolean hasLocalChange​(IResource resource,
                                               IProgressMonitor monitor)
                                        throws CoreException
        For three-way comparisons, this method indicates whether local modifications have been made to the given resource. For two-way comparisons, calling this method has the same effect as calling hasRemoteChange(IResource, IProgressMonitor).
        Parameters:
        resource - the resource being tested
        monitor - a progress monitor
        Returns:
        whether the resource contains local modifications
        Throws:
        CoreException - if the contents could not be compared. Reasons include:
      • hasRemoteChange

        public abstract boolean hasRemoteChange​(IResource resource,
                                                IProgressMonitor monitor)
                                         throws CoreException
        For two-way comparisons, return whether the contents of the corresponding remote differs from the content of the local file in the context of the current operation. By this we mean that this method will return true if the remote contents differ from the local contents.

        For three-way comparisons, return whether the contents of the corresponding remote differ from the contents of the base. In other words, this method returns true if the corresponding remote has changed since the last time the local resource was updated with the remote contents.

        For two-way comparisons, return true if the remote contents differ from the local contents. In this case, this method is equivalent to hasLocalChange(IResource, IProgressMonitor)

        This can be used by clients to determine if they need to fetch the remote contents in order to determine if the resources that constitute the model element are different in the remote location. If the local file exists and the remote file does not, or the remote file exists and the local does not then the contents will be said to differ (i.e. true is returned). Also, implementors will most likely use a timestamp based comparison to determine if the contents differ. This may lead to a situation where true is returned but the actual contents do not differ. Clients must be prepared handle this situation.

        Parameters:
        resource - the local resource
        monitor - a progress monitor, or null if progress reporting is not desired
        Returns:
        whether the contents of the corresponding remote differ from the base.
        Throws:
        CoreException - if the contents could not be compared. Reasons include:
      • isThreeWay

        public abstract boolean isThreeWay()
        Return true if the context is associated with an operation that is using a three-way comparison and false if it is using a two-way comparison.
        Returns:
        whether the context is a three-way or two-way