Class RefMap

java.lang.Object
java.util.AbstractMap<String,Ref>
org.eclipse.jgit.util.RefMap
All Implemented Interfaces:
Map<String,Ref>

public class RefMap extends AbstractMap<String,Ref>
Specialized Map to present a RefDatabase namespace.

Although not declared as a SortedMap, iterators from this map's projections always return references in RefComparator ordering. The map's internal representation is a sorted array of Ref objects, which means lookup and replacement is O(log N), while insertion and removal can be as expensive as O(N + log N) while the list expands or contracts. Since this is not a general map implementation, all entries must be keyed by the reference name.

This class is really intended as a helper for RefDatabase, which needs to perform a merge-join of three sorted RefLists in order to present the unified namespace of the packed-refs file, the loose refs/ directory tree, and the resolved form of any symbolic references.

  • Field Details

    • prefix

      final String prefix
      Prefix denoting the reference subspace this map contains.

      All reference names in this map must start with this prefix. If the prefix is not the empty string, it must end with a '/'.

    • packed

      RefList<Ref> packed
      Immutable collection of the packed references at construction time.
    • loose

      RefList<Ref> loose
      Immutable collection of the loose references at construction time.

      If an entry appears here and in packed, this entry must take precedence, as its more current. Symbolic references in this collection are typically unresolved, so they only tell us who their target is, but not the current value of the target.

    • resolved

      RefList<Ref> resolved
      Immutable collection of resolved symbolic references.

      This collection contains only the symbolic references we were able to resolve at map construction time. Other loose references must be read from loose. Every entry in this list must be matched by an entry in loose, otherwise it might be omitted by the map.

    • size

      int size
    • sizeIsValid

      boolean sizeIsValid
    • entrySet

      private Set<Map.Entry<String,Ref>> entrySet
  • Constructor Details

    • RefMap

      public RefMap()
      Construct an empty map with a small initial capacity.
    • RefMap

      public RefMap(String prefix, RefList<? extends Ref> packed, RefList<? extends Ref> loose, RefList<? extends Ref> resolved)
      Construct a map to merge 3 collections together.
      Parameters:
      prefix - prefix used to slice the lists down. Only references whose names start with this prefix will appear to reside in the map. Must not be null, use "" (the empty string) to select all list items.
      packed - items from the packed reference list, this is the last list searched.
      loose - items from the loose reference list, this list overrides packed if a name appears in both.
      resolved - resolved symbolic references. This list overrides the prior list loose, if an item appears in both. Items in this list must also appear in loose.
  • Method Details