/**
* Method for telling whether a file entry exists.
*
* @param filename The name of the file, the existence of whose entry is to be determined.
* @return Whether the entry exists.
* @throws ArgumentNotValid If the filename is either null or empty.
*/
@Override
public boolean hasEntry(String filename) throws ArgumentNotValid {
ArgumentNotValid.checkNotNullOrEmpty(filename, "String filename");
// See if the file can be found in the database.
return database.existsFileInDB(filename);
}
/**
* Retrieves a set of the names for all the known files.
*
* @return A set of the names for all the known file.
*/
@Override
public Set<String> getAllFileNames() {
// initialise the set
Set<String> res = new HashSet<String>();
// put the collection of filenames into the set.
res.addAll(database.retrieveAllFilenames());
// return the set.
return res;
}
/**
* Method for adding an entry for administration.
*
* @param filename The name of the file to be stored.
* @param msg The StoreMessage of the entry.
* @param checksum The checksum of the entry.
* @throws ArgumentNotValid If either the filename or checksum is either null or the empty string.
*/
@Override
public void addEntry(String filename, StoreMessage msg, String checksum) throws ArgumentNotValid {
ArgumentNotValid.checkNotNullOrEmpty(filename, "String filename");
ArgumentNotValid.checkNotNullOrEmpty(checksum, "String checksum");
// insert this into the entries map.
storeEntries.put(filename, msg);
// insert into database.
database.insertNewFileForUpload(filename, checksum);
}
/**
* Returns the ReplicaStoreState of a given file in a specific replica.
*
* @param filename The name of the file for the ReplicaStoreState.
* @param replicaChannelName The name of the identification channel for uniquely identifying the
* replica of for the ReplicaStoreState.
* @return The ReplicaStoreState of a given file in a specific replica.
* @throws ArgumentNotValid If the filename or the replica id is null or the empty string.
*/
@Override
public ReplicaStoreState getState(String filename, String replicaChannelName)
throws ArgumentNotValid {
ArgumentNotValid.checkNotNullOrEmpty(filename, "String filename");
ArgumentNotValid.checkNotNullOrEmpty(replicaChannelName, "String replicaChannelName");
Replica rep = Channels.retrieveReplicaFromIdentifierChannel(replicaChannelName);
// retrieve the ReplicaStoreState from the database.
return database.getReplicaStoreState(filename, rep.getId());
}
/**
* Retrieves a set with the name of the files with a specific ReplicaStoreState in a specific
* replica.
*
* @param rep The replica where the files belong.
* @param state The ReplicaStoreState for the files.
* @return A set with the names of the files with a specific ReplicaStoreState in a specific
* replica.
* @throws ArgumentNotValid If the Replica or the ReplicaStoreState is null.
*/
@Override
public Set<String> getAllFileNames(Replica rep, ReplicaStoreState state) throws ArgumentNotValid {
ArgumentNotValid.checkNotNull(rep, "Replica rep");
ArgumentNotValid.checkNotNull(state, "ReplicaStoreState state");
// initialise the set
Set<String> res = new HashSet<String>();
// put the collection of filenames into the set.
res.addAll(database.retrieveFilenamesForReplicaEntries(rep.getId(), state));
// return the set.
return res;
}
/**
* Retrieves the checksum of a given file.
*
* @param filename The name of the file, whose checksum should be retrieved.
* @return The checksum of the file.
* @throws ArgumentNotValid If the filename is either null or the empty string.
*/
@Override
public String getCheckSum(String filename) throws ArgumentNotValid {
ArgumentNotValid.checkNotNullOrEmpty(filename, "String filename");
// Ensure that we have the file requested.
if (!hasEntry(filename)) {
throw new UnknownID("Don't know anything about file '" + filename + "'");
}
// Retrieve the checksum for a specific entry.
return database.getChecksum(filename);
}
/**
* Sets the store state of an entry to a specific value.
*
* @param filename The name of the file for the entry.
* @param repChannelId The identification channel of the replica for the entry.
* @param state The new state for the entry.
* @throws ArgumentNotValid If the ReplicaStoreState is null, or if either the filename or the
* replica identification channel is either null or the empty string.
*/
@Override
public void setState(String filename, String repChannelId, ReplicaStoreState state)
throws ArgumentNotValid {
ArgumentNotValid.checkNotNull(state, "ReplicaStoreState state");
ArgumentNotValid.checkNotNullOrEmpty(filename, "String filename");
ArgumentNotValid.checkNotNullOrEmpty(repChannelId, "String repChannelId");
// retrieve the replica
Replica rep = Channels.retrieveReplicaFromIdentifierChannel(repChannelId);
// update the database.
database.setReplicaStoreState(filename, rep.getId(), state);
}
/**
* Determines whether a given file in a specific replica has a valid replica store state. By valid
* means a replica store state other that UNKNOWN_UPLOAD_STATE.
*
* <p>TODO Find out if the assumption that all upload states besides UNKNOWN_UPLOAD_STATE are
* acceptable!
*
* @param filename The name of the file for the ReplicaStoreState.
* @param repChannelId The identification channel of the replica for the ReplicaStoreState.
* @return Whether a given file in a specific replica has a valid store state.
* @throws ArgumentNotValid If either the filenames or the replica identification channel is null
* or the empty string.
*/
@Override
public boolean hasState(String filename, String repChannelId) throws ArgumentNotValid {
ArgumentNotValid.checkNotNullOrEmpty(filename, "String filename");
ArgumentNotValid.checkNotNullOrEmpty(repChannelId, "String repChannelId");
// retrieve the replica
Replica rep = Channels.retrieveReplicaFromIdentifierChannel(repChannelId);
// retrieve the state for the entry for the replica and filename
ReplicaStoreState state = database.getReplicaStoreState(filename, rep.getId());
// return whether the entry has a known upload state
return state != ReplicaStoreState.UNKNOWN_UPLOAD_STATE;
}
/** Constructor. Initialises the access to the database. */
private DatabaseAdmin() {
database = ReplicaCacheDatabase.getInstance();
}
/** Close and cleanup of this class. */
@Override
public void close() {
storeEntries.clear();
database.cleanup();
instance = null;
}
