Class ObjectIdOwnerMap<V extends ObjectIdOwnerMap.Entry>
- java.lang.Object
-
- org.eclipse.jgit.lib.ObjectIdOwnerMap<V>
-
- Type Parameters:
V
- type of subclass of ObjectId that will be stored in the map.
- All Implemented Interfaces:
java.lang.Iterable<V>
public class ObjectIdOwnerMap<V extends ObjectIdOwnerMap.Entry> extends java.lang.Object implements java.lang.Iterable<V>
Fast, efficient map forObjectId
subclasses in only one map.To use this map type, applications must have their entry value type extend from
ObjectIdOwnerMap.Entry
, which itself extends from ObjectId.Object instances may only be stored in ONE ObjectIdOwnerMap. This restriction exists because the map stores internal map state within each object instance. If an instance is be placed in another ObjectIdOwnerMap it could corrupt one or both map's internal state.
If an object instance must be in more than one map, applications may use ObjectIdOwnerMap for one of the maps, and
ObjectIdSubclassMap
for the other map(s). It is encouraged to use ObjectIdOwnerMap for the map that is accessed most often, as this implementation runs faster than the more general ObjectIdSubclassMap implementation.
-
-
Nested Class Summary
Nested Classes Modifier and Type Class Description static class
ObjectIdOwnerMap.Entry
Type of entry stored in theObjectIdOwnerMap
.
-
Constructor Summary
Constructors Constructor Description ObjectIdOwnerMap()
Create an empty map.
-
Method Summary
All Methods Instance Methods Concrete Methods Modifier and Type Method Description <Q extends V>
voidadd(Q newValue)
Store an object for future lookup.<Q extends V>
VaddIfAbsent(Q newValue)
Store an object for future lookup.void
clear()
Remove all entries from this map.boolean
contains(AnyObjectId toFind)
Returns true if this map contains the specified object.V
get(AnyObjectId toFind)
Lookup an existing mapping.boolean
isEmpty()
java.util.Iterator<V>
iterator()
int
size()
-
-
-
Method Detail
-
clear
public void clear()
Remove all entries from this map.
-
get
public V get(AnyObjectId toFind)
Lookup an existing mapping.- Parameters:
toFind
- the object identifier to find.- Returns:
- the instance mapped to toFind, or null if no mapping exists.
-
contains
public boolean contains(AnyObjectId toFind)
Returns true if this map contains the specified object.- Parameters:
toFind
- object to find.- Returns:
- true if the mapping exists for this object; false otherwise.
-
add
public <Q extends V> void add(Q newValue)
Store an object for future lookup.An existing mapping for must not be in this map. Callers must first call
get(AnyObjectId)
to verify there is no current mapping prior to adding a new mapping, or useaddIfAbsent(Entry)
.- Type Parameters:
Q
- type of instance to store.- Parameters:
newValue
- the object to store.
-
addIfAbsent
public <Q extends V> V addIfAbsent(Q newValue)
Store an object for future lookup.Stores
newValue
, but only if there is not already an object for the same object name. Callers can tell if the value is new by checking the return value with reference equality:V obj = ...; boolean wasNew = map.addIfAbsent(obj) == obj;
- Type Parameters:
Q
- type of instance to store.- Parameters:
newValue
- the object to store.- Returns:
newValue
if stored, or the prior value already stored and that would have been returned had the caller usedget(newValue)
first.
-
size
public int size()
- Returns:
- number of objects in this map.
-
isEmpty
public boolean isEmpty()
- Returns:
- true if
size()
is 0.
-
iterator
public java.util.Iterator<V> iterator()
- Specified by:
iterator
in interfacejava.lang.Iterable<V extends ObjectIdOwnerMap.Entry>
-
-