Class RefMap

  extended by java.util.AbstractMap<String,Ref>
      extended by org.eclipse.jgit.util.RefMap
All Implemented Interfaces:

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.

Nested Class Summary
Nested classes/interfaces inherited from class java.util.AbstractMap
AbstractMap.SimpleEntry<K,V>, AbstractMap.SimpleImmutableEntry<K,V>
Nested classes/interfaces inherited from interface java.util.Map
Constructor Summary
          Construct an empty map with a small initial capacity.
RefMap(String prefix, RefList<? extends Ref> packed, RefList<? extends Ref> loose, RefList<? extends Ref> resolved)
          Construct a map to merge 3 collections together.
Method Summary
 boolean containsKey(Object name)
 Set<Map.Entry<String,Ref>> entrySet()
 Ref get(Object key)
 boolean isEmpty()
 Ref put(String keyName, Ref value)
 Ref remove(Object key)
 String toString()
Methods inherited from class java.util.AbstractMap
clear, clone, containsValue, equals, hashCode, keySet, putAll, size, values
Methods inherited from class java.lang.Object
finalize, getClass, notify, notifyAll, wait, wait, wait

Constructor Detail


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


public RefMap(String prefix,
              RefList<? extends Ref> packed,
              RefList<? extends Ref> loose,
              RefList<? extends Ref> resolved)
Construct a map to merge 3 collections together.

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 Detail


public boolean containsKey(Object name)
Specified by:
containsKey in interface Map<String,Ref>
containsKey in class AbstractMap<String,Ref>


public Ref get(Object key)
Specified by:
get in interface Map<String,Ref>
get in class AbstractMap<String,Ref>


public Ref put(String keyName,
               Ref value)
Specified by:
put in interface Map<String,Ref>
put in class AbstractMap<String,Ref>


public Ref remove(Object key)
Specified by:
remove in interface Map<String,Ref>
remove in class AbstractMap<String,Ref>


public boolean isEmpty()
Specified by:
isEmpty in interface Map<String,Ref>
isEmpty in class AbstractMap<String,Ref>


public Set<Map.Entry<String,Ref>> entrySet()
Specified by:
entrySet in interface Map<String,Ref>
Specified by:
entrySet in class AbstractMap<String,Ref>


public String toString()
toString in class AbstractMap<String,Ref>

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