Interface IResourceMappingMerger

  • All Known Implementing Classes:
    AbstractResourceMappingMerger, ResourceMappingMerger

    public interface IResourceMappingMerger
    The purpose of this interface is to provide support for model level auto-merging. It is helpful in the cases where a file may contain multiple model elements or a model element consists of multiple files. It can also be used for cases where there is a one-to-one mapping between model elements and files, although IStorageMerger can also be used in that case. Clients should group resource mappings by model provider and then attempt to obtain a merger from the model provider using the adaptable mechanism as follows:
          Object o = mapping.getModelProvider().getAdapter(IResourceMappingMerger.class);
          if (o instanceof IResourceMappingMerger.class) {
             IResourceMappingMerger merger = (IResourceMappingMerger)o;
             ...
          }
     
    Since:
    3.2
    See Also:
    ResourceMappingMerger, IStorageMerger, ResourceMapping, ModelProvider, IMergeContext
    Restriction:
    This interface is not intended to be implemented by clients. Client should subclass ResourceMappingMerger instead.
    • Method Detail

      • merge

        IStatus merge​(IMergeContext mergeContext,
                      IProgressMonitor monitor)
               throws CoreException
        Attempt to automatically merge the mappings of the merge context(MergeContext#getMappings()). The merge context provides access to the out-of-sync resources (MergeContext#getSyncInfoTree()) associated with the mappings to be merged. The set of provided mappings may come from multiple model providers. A particular implementation of this interface should only merge the mappings associated with their model provider. Also, the set of resources may contain additional resources that are not part of the mappings being merged. Implementors of this interface should use the mappings to determine which resources to merge and what additional semantics can be used to attempt the merge.

        The type of merge to be performed depends on what is returned by the MergeContext#getType() method. If the type is MergeContext.TWO_WAY the merge will replace the local contents with the remote contents, ignoring any local changes. For THREE_WAY, the base is used to attempt to merge remote changes with local changes.

        If merging was not possible for one or more of the mappings to which this merge applies, these mappings should be returned in an MergeStatus whose code is MergeStatus.CONFLICTS and which provides access to the mappings which could not be merged. Note that it is up to the model to decide whether it wants to break one of the provided resource mappings into several sub-mappings and attempt auto-merging at that level.

        Parameters:
        mergeContext - a context that provides access to the resources involved in the merge. The context must not be null.
        monitor - a progress monitor
        Returns:
        a status indicating the results of the operation. A code of MergeStatus.CONFLICTS indicates that some or all of the resource mappings could not be merged. The mappings that were not merged are available using MergeStatus#getConflictingMappings()
        Throws:
        CoreException - if errors occurred
      • getMergeRule

        ISchedulingRule getMergeRule​(IMergeContext context)
        Return the scheduling rule that is required to merge all the changes that apply to this merger in the given context. When calling merge(IMergeContext, IProgressMonitor), clients must ensure that they either have obtained a rule that covers the rule returned by this method or they must not hold any rule.
        Parameters:
        context - the context that contains the changes to be merged
        Returns:
        the scheduling rule required by this merger to merge all the changes in the given context belonging to the merger's model provider.
      • validateMerge

        IStatus validateMerge​(IMergeContext mergeContext,
                              IProgressMonitor monitor)
        Validate an auto-merge for the given context. This method must be invoked for all mergers involved in the merge before the auto-merge is attempted. The purpose of the validation is to indicate whether there are conditions in the merge context that make an auto-merge undesirable. The purpose is not to indicate that conflicts exist (this is done by the merge method) but instead to indicate that the nature of one of more incoming changes is such that performing an auto-merge may be undesirable.

        Clients should validate before performing the merge and, if any of the returned status are not OK, should prompt the user to make them aware of the potential side effects. The user may still decide to attempt an auto-merge, in which case the client may still invoke the merge method.

        Parameters:
        mergeContext - a context that provides access to the resources involved in the merge. The context must not be null.
        monitor - a progress monitor
        Returns:
        a status indicating any potential side effects of performing an auto-merge.