abstract class BaseDirCacheEditor
extends java.lang.Object
DirCache
.
The different update strategies extend this class to provide their own unique services to applications.
Modifier and Type | Field and Description |
---|---|
protected DirCache |
cache
The cache instance this editor updates during
finish() . |
protected DirCacheEntry[] |
entries
Entry table this builder will eventually replace into
cache . |
protected int |
entryCnt
Total number of valid entries in
entries . |
Modifier | Constructor and Description |
---|---|
protected |
BaseDirCacheEditor(DirCache dc,
int ecnt)
Construct a new editor.
|
Modifier and Type | Method and Description |
---|---|
private void |
checkNameConflicts() |
boolean |
commit()
Finish, write, commit this change, and release the index lock.
|
protected void |
fastAdd(DirCacheEntry newEntry)
Append one entry into the resulting entry list.
|
protected void |
fastKeep(int pos,
int cnt)
Add a range of existing entries from the destination cache.
|
abstract void |
finish()
Finish this builder and update the destination
DirCache . |
DirCache |
getDirCache()
Get the
DirCache |
private static int |
lastSlash(byte[] path) |
private static int |
nextSlash(byte[] b,
int p) |
protected void |
replace()
Update the DirCache with the contents of
entries . |
private static boolean |
startsWith(byte[] a,
byte[] b,
int n) |
protected DirCacheEntry[] entries
cache
.
Use fastAdd(DirCacheEntry)
or fastKeep(int, int)
to
make additions to this table. The table is automatically expanded if it
is too small for a new addition.
Typically the entries in here are sorted by their path names, just like they are in the DirCache instance.
protected int entryCnt
entries
.protected BaseDirCacheEditor(DirCache dc, int ecnt)
dc
- the cache this editor will eventually update.ecnt
- estimated number of entries the editor will have upon
completion. This sizes the initial entry table.public DirCache getDirCache()
DirCache
finish()
.protected void fastAdd(DirCacheEntry newEntry)
The entry is placed at the end of the entry list. The caller is responsible for making sure the final table is correctly sorted.
The entries
table is automatically expanded if there is
insufficient space for the new addition.
newEntry
- the new entry to add.protected void fastKeep(int pos, int cnt)
The entries are placed at the end of the entry list, preserving their current order. The caller is responsible for making sure the final table is correctly sorted.
This method copies from the destination cache, which has not yet been updated with this editor's new table. So all offsets into the destination cache are not affected by any updates that may be currently taking place in this editor.
The entries
table is automatically expanded if there is
insufficient space for the new additions.
pos
- first entry to copy from the destination cache.cnt
- number of entries to copy.public abstract void finish()
DirCache
.
When this method completes this builder instance is no longer usable by the calling application. A new builder must be created to make additional changes to the index entries.
After completion the DirCache returned by getDirCache()
will
contain all modifications.
Note to implementors: Make sure entries
is fully sorted
then invoke replace()
to update the DirCache with the new table.
protected void replace()
private void checkNameConflicts()
private static int lastSlash(byte[] path)
private static int nextSlash(byte[] b, int p)
private static boolean startsWith(byte[] a, byte[] b, int n)
public boolean commit() throws java.io.IOException
If this method fails (returns false) the lock is still released.
This is a utility method for applications as the finish-write-commit pattern is very common after using a builder to update entries.
java.lang.IllegalStateException
- the lock is not held.java.io.IOException
- the output file could not be created. The caller no longer
holds the lock.