JGit 7.2.0.202503040940-r · org.eclipse.jgit.lib.ObjectIdOwnerMap

Fast, efficient map for org.eclipse.jgit.lib.ObjectId subclasses in only one map.

To use this map type, applications must have their entry value type extend from org.eclipse.jgit.lib.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 org.eclipse.jgit.lib.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 and Inner Type Summary

Modifier and Type	Class and Description
public abstract static class	ObjectIdOwnerMap.Entry Type of entry stored in the `ObjectIdOwnerMap`.

Field Summary

Modifier and Type	Field and Description
pack-priv int	bits Number of low bits used to form the index into `directory`.
pack-priv V[][]	directory Top level directory of the segments.
private int	grow The map doubles in capacity when `size` reaches this target.
private static final int	INITIAL_DIRECTORY Size of the initial directory, will grow as necessary.
private int	mask Low bit mask to index into `directory`, `2^bits-1`.
private static final int	SEGMENT_BITS Number of bits in a segment's index.
private static final int	SEGMENT_SHIFT
pack-priv int	size Total number of objects in this map.

Constructor Summary

Access	Constructor and Description
public	ObjectIdOwnerMap() Create an empty map.

Method Summary

Modifier and Type	Method and Description
public < type of values Q extends V> void	add(Q the object to store. newValue) Store an object for future lookup.
public < type of values Q extends V> V	Returns: `newValue` if stored, or the prior value already stored and that would have been returned had the caller used `get(newValue)` first. addIfAbsent(Q the object to store. newValue) Store an object for future lookup.
public void	clear() Remove all entries from this map.
private static final int	computeGrowAt(int bits)
public boolean	contains(AnyObjectId the objectId to find toFind) Implements org.eclipse.jgit.lib.ObjectIdSet.contains. Returns true if the objectId is contained within the collection.
private static final boolean	equals(AnyObjectId firstObjectId, AnyObjectId secondObjectId)
public V	Returns: the instance mapped to toFind, or null if no mapping exists. get(AnyObjectId the object identifier to find. toFind) Lookup an existing mapping.
private void	grow()
public boolean	Returns: true if `size()` is 0. isEmpty() Whether this map is empty
public Iterator<V>	iterator() Implements java.lang.Iterable.iterator. Returns an iterator over elements of type `T`.
private final V[]	newSegment()
public int	Returns: number of objects in this map. size() Get number of objects in this map.

Inherited from java.lang.Object:: clone equals finalize getClass hashCode notify notifyAll toString wait wait wait

Field Detail

bits	back to summary
pack-priv int bits Number of low bits used to form the index into `directory`.

directory back to summary

directory	back to summary
pack-priv V[][] directory Top level directory of the segments. The low `bits` of the SHA-1 are used to select the segment from this directory. Each segment is constant sized at 2^SEGMENT_BITS.

pack-priv V[][] directory

Top level directory of the segments.

The low bits of the SHA-1 are used to select the segment from this directory. Each segment is constant sized at 2^SEGMENT_BITS.

grow	back to summary
private int grow The map doubles in capacity when `size` reaches this target.

INITIAL_DIRECTORY	back to summary
private static final int INITIAL_DIRECTORY Size of the initial directory, will grow as necessary.

mask	back to summary
private int mask Low bit mask to index into `directory`, `2^bits-1`.

SEGMENT_BITS	back to summary
private static final int SEGMENT_BITS Number of bits in a segment's index. Segments are 2^11 in size.

SEGMENT_SHIFT	back to summary
private static final int SEGMENT_SHIFT

size	back to summary
pack-priv int size Total number of objects in this map.

Constructor Detail

ObjectIdOwnerMap	back to summary
public ObjectIdOwnerMap() Create an empty map. Annotations @SuppressWarnings:unchecked

ObjectIdOwnerMap

back to summary

public ObjectIdOwnerMap()

Create an empty map.

Annotations

@SuppressWarnings:unchecked

Method Detail

add back to summary

add	back to summary
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 use `addIfAbsent(Entry)`. Parameters <Q> type of values newValue:Q the object to store.

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 use addIfAbsent(Entry).

Parameters

<Q>: type of values
newValue:Q: the object to store.

addIfAbsent back to summary

addIfAbsent	back to summary
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; Parameters <Q> type of values newValue:Q the object to store. Returns:V `newValue` if stored, or the prior value already stored and that would have been returned had the caller used `get(newValue)` first. Annotations @SuppressWarnings:unchecked

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;

Parameters

<Q>: type of values
newValue:Q: the object to store.

Returns:V

newValue if stored, or the prior value already stored and that would have been returned had the caller used get(newValue) first.

Annotations

@SuppressWarnings:unchecked

clear	back to summary
public void clear() Remove all entries from this map.

computeGrowAt	back to summary
private static final int computeGrowAt(int bits)

contains	back to summary
public boolean contains(AnyObjectId toFind) Implements org.eclipse.jgit.lib.ObjectIdSet.contains. Doc from org.eclipse.jgit.lib.ObjectIdSet.contains. Returns true if the objectId is contained within the collection. Returns true if this map contains the specified object. Parameters toFind:AnyObjectId the objectId to find Returns:boolean whether the collection contains the objectId. Annotations @Override

contains

back to summary

public boolean contains(AnyObjectId toFind)

Implements org.eclipse.jgit.lib.ObjectIdSet.contains.

Doc from org.eclipse.jgit.lib.ObjectIdSet.contains.

Returns true if the objectId is contained within the collection.

Returns true if this map contains the specified object.

Parameters

toFind:AnyObjectId: the objectId to find

Returns:boolean

whether the collection contains the objectId.

Annotations

@Override

equals	back to summary
private static final boolean equals(AnyObjectId firstObjectId, AnyObjectId secondObjectId)

get	back to summary
public V get(AnyObjectId toFind) Lookup an existing mapping. Parameters toFind:AnyObjectId the object identifier to find. Returns:V the instance mapped to toFind, or null if no mapping exists. Annotations @SuppressWarnings:unchecked

get

back to summary

public V get(AnyObjectId toFind)

Lookup an existing mapping.

Parameters

toFind:AnyObjectId: the object identifier to find.

Returns:V

the instance mapped to toFind, or null if no mapping exists.

Annotations

@SuppressWarnings:unchecked

grow	back to summary
private void grow() Annotations @SuppressWarnings:unchecked

isEmpty back to summary

isEmpty	back to summary
public boolean isEmpty() Whether this map is empty Returns:boolean true if `size()` is 0.

public boolean isEmpty()

Whether this map is empty

Returns:boolean: true if size() is 0.

iterator back to summary

iterator	back to summary
public Iterator<V> iterator() Implements java.lang.Iterable.iterator. Doc from java.lang.Iterable.iterator. Returns an iterator over elements of type `T`. Returns:Iterator<V> an Iterator. Annotations @Override

public Iterator<V> iterator()

Implements java.lang.Iterable.iterator.

Doc from java.lang.Iterable.iterator.

Returns an iterator over elements of type T.

Returns:Iterator<V>

an Iterator.

Annotations

@Override

newSegment	back to summary
private final V[] newSegment() Annotations @SuppressWarnings:unchecked

size	back to summary
public int size() Get number of objects in this map. Returns:int number of objects in this map.

size

back to summary

public int size()

Get number of objects in this map.

Returns:int: number of objects in this map.

public Class ObjectIdOwnerMap<V extends ObjectIdOwnerMap.Entry>

Nested and Inner Type Summary

Field Summary

Constructor Summary

Method Summary

Field Detail

Constructor Detail

Method Detail

public abstract Class ObjectIdOwnerMap.Entry

Field Summary

Constructor Summary

Method Summary

Field Detail

Constructor Detail