/**
* Releases the repository acquired via {@link #add} or {@link #get} method. Decrements an
* openCounter for the repository and if it reaches 0 repository is closed and removed from the
* cache. Does nothing if repository is not present found in the cache.
*
* @param db repository to release
*/
synchronized void release(@NotNull Repository db) {
RepositoryCache.FileKey key = RepositoryCache.FileKey.exact(db.getDirectory(), FS.DETECTED);
CachedRepository cachedRepository = myRepositories.get(key);
if (cachedRepository != null
&& cachedRepository.getRepository() == db
&& cachedRepository.dec() == 0) {
myRepositories.remove(key);
db.close();
}
}
/**
* Returns a repository for the given key or null if repository is not found in cache. If
* repository is found its openCounter is incremented. When the caller is done with repository it
* must call {@link #release} method.
*
* @param key repository key
* @return see above
*/
@Nullable
synchronized Repository get(@NotNull RepositoryCache.FileKey key) {
CachedRepository cachedRepository = myRepositories.get(key);
if (cachedRepository != null) {
Repository result = cachedRepository.getRepository();
cachedRepository.inc();
return result;
}
return null;
}
/**
* Adds a new repository with the specified key in cache. Returns the added repository if there
* was no repository in cache associated with the given key, otherwise existing repository
* associated with the key is returned and its openCounter is incremented. When the caller is done
* with repository it must call the {@link #release} method.
*
* @param key repository key
* @param db repository
* @return see above
*/
@NotNull
synchronized Repository add(@NotNull RepositoryCache.FileKey key, @NotNull Repository db) {
CachedRepository existing = myRepositories.get(key);
if (existing == null) {
myRepositories.put(key, new CachedRepository(db));
return db;
} else {
Repository result = existing.getRepository();
existing.inc();
return result;
}
}