diff --git a/components/net/sf/briar/db/DatabaseComponentImpl.java b/components/net/sf/briar/db/DatabaseComponentImpl.java
index 7ccc8277ec20591319668275f6b9fb9489d26aaa..ccb162b80cd9ed90e0ca4be8cc6e7ac026e3938f 100644
--- a/components/net/sf/briar/db/DatabaseComponentImpl.java
+++ b/components/net/sf/briar/db/DatabaseComponentImpl.java
@@ -21,13 +21,13 @@ import net.sf.briar.api.protocol.MessageId;
* Abstract superclass containing code shared by ReadWriteLockDatabaseComponent
* and SynchronizedDatabaseComponent.
*/
-abstract class DatabaseComponentImpl<Txn> implements DatabaseComponent,
+abstract class DatabaseComponentImpl<T> implements DatabaseComponent,
DatabaseCleaner.Callback {
private static final Logger LOG =
Logger.getLogger(DatabaseComponentImpl.class.getName());
- protected final Database<Txn> db;
+ protected final Database<T> db;
protected final DatabaseCleaner cleaner;
private final List<DatabaseListener> listeners =
@@ -38,7 +38,7 @@ DatabaseCleaner.Callback {
private long timeOfLastCheck = 0L; // Locking: spaceLock
private volatile boolean writesAllowed = true;
- DatabaseComponentImpl(Database<Txn> db, DatabaseCleaner cleaner) {
+ DatabaseComponentImpl(Database<T> db, DatabaseCleaner cleaner) {
this.db = db;
this.cleaner = cleaner;
}
@@ -71,7 +71,7 @@ DatabaseCleaner.Callback {
* <p>
* Locking: messages write.
*/
- private int calculateSendability(Txn txn, Message m) throws DbException {
+ private int calculateSendability(T txn, Message m) throws DbException {
int sendability = 0;
// One point for a good rating
if(db.getRating(txn, m.getAuthor()) == Rating.GOOD) sendability++;
@@ -121,7 +121,7 @@ DatabaseCleaner.Callback {
* Locking: contacts read.
*/
protected boolean containsContact(ContactId c) throws DbException {
- Txn txn = db.startTransaction();
+ T txn = db.startTransaction();
try {
boolean contains = db.containsContact(txn, c);
db.commitTransaction(txn);
@@ -137,7 +137,7 @@ DatabaseCleaner.Callback {
* <p>
* Locking: contacts read, messages write, messageStatuses write.
*/
- protected void removeMessage(Txn txn, MessageId id) throws DbException {
+ protected void removeMessage(T txn, MessageId id) throws DbException {
Integer sendability = db.getSendability(txn, id);
assert sendability != null;
// If the message is sendable, deleting it may affect its ancestors'
@@ -176,7 +176,7 @@ DatabaseCleaner.Callback {
* <p>
* Locking: contacts read, messages write, messageStatuses write.
*/
- protected boolean storeGroupMessage(Txn txn, Message m, ContactId sender)
+ protected boolean storeGroupMessage(T txn, Message m, ContactId sender)
throws DbException {
if(m.getGroup() == null) throw new IllegalArgumentException();
boolean stored = db.addGroupMessage(txn, m);
@@ -204,7 +204,7 @@ DatabaseCleaner.Callback {
* Attempts to store the given messages, received from the given contact,
* and returns true if any were stored.
*/
- protected boolean storeMessages(Txn txn, ContactId c,
+ protected boolean storeMessages(T txn, ContactId c,
Collection<Message> messages) throws DbException {
boolean anyStored = false;
for(Message m : messages) {
@@ -226,7 +226,7 @@ DatabaseCleaner.Callback {
* <p>
* Locking: contacts read, messages write, messageStatuses write.
*/
- protected boolean storePrivateMessage(Txn txn, Message m, ContactId c,
+ protected boolean storePrivateMessage(T txn, Message m, ContactId c,
boolean incoming) throws DbException {
if(m.getGroup() != null) throw new IllegalArgumentException();
if(m.getAuthor() != null) throw new IllegalArgumentException();
@@ -250,7 +250,7 @@ DatabaseCleaner.Callback {
* @param increment True if the message's sendability has changed from 0 to
* greater than 0, or false if it has changed from greater than 0 to 0.
*/
- private int updateAncestorSendability(Txn txn, MessageId m,
+ private int updateAncestorSendability(T txn, MessageId m,
boolean increment) throws DbException {
int affected = 0;
boolean changed = true;
@@ -285,7 +285,7 @@ DatabaseCleaner.Callback {
* @param increment True if the user's rating for the author has changed
* from not good to good, or false if it has changed from good to not good.
*/
- protected void updateAuthorSendability(Txn txn, AuthorId a,
+ protected void updateAuthorSendability(T txn, AuthorId a,
boolean increment) throws DbException {
int direct = 0, indirect = 0;
for(MessageId id : db.getMessagesByAuthor(txn, a)) {
diff --git a/components/net/sf/briar/db/ReadWriteLockDatabaseComponent.java b/components/net/sf/briar/db/ReadWriteLockDatabaseComponent.java
index f7c50d561935120326e6bca2044fdf38ee9d03ea..2800184cda340de0487c3f5ab6d9e402275f446e 100644
--- a/components/net/sf/briar/db/ReadWriteLockDatabaseComponent.java
+++ b/components/net/sf/briar/db/ReadWriteLockDatabaseComponent.java
@@ -38,9 +38,11 @@ import com.google.inject.Inject;
/**
* An implementation of DatabaseComponent using reentrant read-write locks.
- * This implementation can allow writers to starve.
+ * Depending on the JVM's read-write lock implementation, this implementation
+ * may allow writers to starve. LockFairnessTest can be used to test whether
+ * this implementation is safe on a given JVM.
*/
-class ReadWriteLockDatabaseComponent<Txn> extends DatabaseComponentImpl<Txn> {
+class ReadWriteLockDatabaseComponent<T> extends DatabaseComponentImpl<T> {
private static final Logger LOG =
Logger.getLogger(ReadWriteLockDatabaseComponent.class.getName());
@@ -66,7 +68,7 @@ class ReadWriteLockDatabaseComponent<Txn> extends DatabaseComponentImpl<Txn> {
new ReentrantReadWriteLock(true);
@Inject
- ReadWriteLockDatabaseComponent(Database<Txn> db, DatabaseCleaner cleaner) {
+ ReadWriteLockDatabaseComponent(Database<T> db, DatabaseCleaner cleaner) {
super(db, cleaner);
}
@@ -77,7 +79,7 @@ class ReadWriteLockDatabaseComponent<Txn> extends DatabaseComponentImpl<Txn> {
try {
messageStatusLock.writeLock().lock();
try {
- Txn txn = db.startTransaction();
+ T txn = db.startTransaction();
try {
for(MessageId m : db.getOldMessages(txn, size)) {
removeMessage(txn, m);
@@ -111,7 +113,7 @@ class ReadWriteLockDatabaseComponent<Txn> extends DatabaseComponentImpl<Txn> {
try {
transportLock.writeLock().lock();
try {
- Txn txn = db.startTransaction();
+ T txn = db.startTransaction();
try {
c = db.addContact(txn, transports, secret);
db.commitTransaction(txn);
@@ -143,7 +145,7 @@ class ReadWriteLockDatabaseComponent<Txn> extends DatabaseComponentImpl<Txn> {
try {
subscriptionLock.readLock().lock();
try {
- Txn txn = db.startTransaction();
+ T txn = db.startTransaction();
try {
// Don't store the message if the user has
// unsubscribed from the group or the message
@@ -184,7 +186,7 @@ class ReadWriteLockDatabaseComponent<Txn> extends DatabaseComponentImpl<Txn> {
try {
messageStatusLock.writeLock().lock();
try {
- Txn txn = db.startTransaction();
+ T txn = db.startTransaction();
try {
added = storePrivateMessage(txn, m, c, false);
db.commitTransaction(txn);
@@ -215,7 +217,7 @@ class ReadWriteLockDatabaseComponent<Txn> extends DatabaseComponentImpl<Txn> {
try {
messageStatusLock.writeLock().lock();
try {
- Txn txn = db.startTransaction();
+ T txn = db.startTransaction();
try {
lost = db.getLostBatches(txn, c);
db.commitTransaction(txn);
@@ -240,7 +242,7 @@ class ReadWriteLockDatabaseComponent<Txn> extends DatabaseComponentImpl<Txn> {
try {
messageStatusLock.writeLock().lock();
try {
- Txn txn = db.startTransaction();
+ T txn = db.startTransaction();
try {
if(LOG.isLoggable(Level.FINE))
LOG.fine("Removing lost batch");
@@ -269,7 +271,7 @@ class ReadWriteLockDatabaseComponent<Txn> extends DatabaseComponentImpl<Txn> {
if(!containsContact(c)) throw new NoSuchContactException();
messageStatusLock.writeLock().lock();
try {
- Txn txn = db.startTransaction();
+ T txn = db.startTransaction();
try {
Collection<BatchId> acks = db.getBatchesToAck(txn, c);
Collection<BatchId> sent = new ArrayList<BatchId>();
@@ -307,7 +309,7 @@ class ReadWriteLockDatabaseComponent<Txn> extends DatabaseComponentImpl<Txn> {
try {
subscriptionLock.readLock().lock();
try {
- Txn txn = db.startTransaction();
+ T txn = db.startTransaction();
try {
sent = new ArrayList<MessageId>();
int capacity = b.getCapacity();
@@ -338,7 +340,7 @@ class ReadWriteLockDatabaseComponent<Txn> extends DatabaseComponentImpl<Txn> {
BatchId id = b.finish();
messageStatusLock.writeLock().lock();
try {
- Txn txn = db.startTransaction();
+ T txn = db.startTransaction();
try {
db.addOutstandingBatch(txn, c, id, sent);
db.commitTransaction(txn);
@@ -369,7 +371,7 @@ class ReadWriteLockDatabaseComponent<Txn> extends DatabaseComponentImpl<Txn> {
try{
subscriptionLock.readLock().lock();
try {
- Txn txn = db.startTransaction();
+ T txn = db.startTransaction();
try {
sent = new ArrayList<MessageId>();
considered = new ArrayList<MessageId>();
@@ -406,7 +408,7 @@ class ReadWriteLockDatabaseComponent<Txn> extends DatabaseComponentImpl<Txn> {
BatchId id = b.finish();
messageStatusLock.writeLock().lock();
try {
- Txn txn = db.startTransaction();
+ T txn = db.startTransaction();
try {
db.addOutstandingBatch(txn, c, id, sent);
db.commitTransaction(txn);
@@ -435,7 +437,7 @@ class ReadWriteLockDatabaseComponent<Txn> extends DatabaseComponentImpl<Txn> {
try {
messageStatusLock.readLock().lock();
try {
- Txn txn = db.startTransaction();
+ T txn = db.startTransaction();
try {
Collection<MessageId> sendable =
db.getSendableMessages(txn, c, Integer.MAX_VALUE);
@@ -474,7 +476,7 @@ class ReadWriteLockDatabaseComponent<Txn> extends DatabaseComponentImpl<Txn> {
if(!containsContact(c)) throw new NoSuchContactException();
subscriptionLock.readLock().lock();
try {
- Txn txn = db.startTransaction();
+ T txn = db.startTransaction();
try {
Map<Group, Long> subs = db.getVisibleSubscriptions(txn, c);
s.writeSubscriptions(subs, System.currentTimeMillis());
@@ -503,7 +505,7 @@ class ReadWriteLockDatabaseComponent<Txn> extends DatabaseComponentImpl<Txn> {
if(!containsContact(c)) throw new NoSuchContactException();
transportLock.readLock().lock();
try {
- Txn txn = db.startTransaction();
+ T txn = db.startTransaction();
try {
Map<String, Map<String, String>> transports =
db.getTransports(txn);
@@ -533,7 +535,7 @@ class ReadWriteLockDatabaseComponent<Txn> extends DatabaseComponentImpl<Txn> {
if(!containsContact(c)) throw new NoSuchContactException();
windowLock.readLock().lock();
try {
- Txn txn = db.startTransaction();
+ T txn = db.startTransaction();
try {
ConnectionWindow w =
db.getConnectionWindow(txn, c, transportId);
@@ -554,7 +556,7 @@ class ReadWriteLockDatabaseComponent<Txn> extends DatabaseComponentImpl<Txn> {
public Collection<ContactId> getContacts() throws DbException {
contactLock.readLock().lock();
try {
- Txn txn = db.startTransaction();
+ T txn = db.startTransaction();
try {
Collection<ContactId> contacts = db.getContacts(txn);
db.commitTransaction(txn);
@@ -571,7 +573,7 @@ class ReadWriteLockDatabaseComponent<Txn> extends DatabaseComponentImpl<Txn> {
public Rating getRating(AuthorId a) throws DbException {
ratingLock.readLock().lock();
try {
- Txn txn = db.startTransaction();
+ T txn = db.startTransaction();
try {
Rating r = db.getRating(txn, a);
db.commitTransaction(txn);
@@ -589,7 +591,7 @@ class ReadWriteLockDatabaseComponent<Txn> extends DatabaseComponentImpl<Txn> {
contactLock.readLock().lock();
try {
if(!containsContact(c)) throw new NoSuchContactException();
- Txn txn = db.startTransaction();
+ T txn = db.startTransaction();
try {
byte[] secret = db.getSharedSecret(txn, c);
db.commitTransaction(txn);
@@ -606,7 +608,7 @@ class ReadWriteLockDatabaseComponent<Txn> extends DatabaseComponentImpl<Txn> {
public Collection<Group> getSubscriptions() throws DbException {
subscriptionLock.readLock().lock();
try {
- Txn txn = db.startTransaction();
+ T txn = db.startTransaction();
try {
Collection<Group> subs = db.getSubscriptions(txn);
db.commitTransaction(txn);
@@ -624,7 +626,7 @@ class ReadWriteLockDatabaseComponent<Txn> extends DatabaseComponentImpl<Txn> {
throws DbException {
transportLock.readLock().lock();
try {
- Txn txn = db.startTransaction();
+ T txn = db.startTransaction();
try {
Map<String, String> config = db.getTransportConfig(txn, name);
db.commitTransaction(txn);
@@ -641,7 +643,7 @@ class ReadWriteLockDatabaseComponent<Txn> extends DatabaseComponentImpl<Txn> {
public Map<String, Map<String, String>> getTransports() throws DbException {
transportLock.readLock().lock();
try {
- Txn txn = db.startTransaction();
+ T txn = db.startTransaction();
try {
Map<String, Map<String, String>> transports =
db.getTransports(txn);
@@ -663,7 +665,7 @@ class ReadWriteLockDatabaseComponent<Txn> extends DatabaseComponentImpl<Txn> {
if(!containsContact(c)) throw new NoSuchContactException();
transportLock.readLock().lock();
try {
- Txn txn = db.startTransaction();
+ T txn = db.startTransaction();
try {
Map<String, Map<String, String>> transports =
db.getTransports(txn, c);
@@ -686,7 +688,7 @@ class ReadWriteLockDatabaseComponent<Txn> extends DatabaseComponentImpl<Txn> {
try {
subscriptionLock.readLock().lock();
try {
- Txn txn = db.startTransaction();
+ T txn = db.startTransaction();
try {
Collection<ContactId> visible = db.getVisibility(txn, g);
db.commitTransaction(txn);
@@ -713,7 +715,7 @@ class ReadWriteLockDatabaseComponent<Txn> extends DatabaseComponentImpl<Txn> {
try {
subscriptionLock.readLock().lock();
try {
- Txn txn = db.startTransaction();
+ T txn = db.startTransaction();
try {
boolean has = db.hasSendableMessages(txn, c);
db.commitTransaction(txn);
@@ -747,7 +749,7 @@ class ReadWriteLockDatabaseComponent<Txn> extends DatabaseComponentImpl<Txn> {
try {
Collection<BatchId> acks = a.getBatchIds();
for(BatchId ack : acks) {
- Txn txn = db.startTransaction();
+ T txn = db.startTransaction();
try {
db.removeAckedBatch(txn, c, ack);
db.commitTransaction(txn);
@@ -781,7 +783,7 @@ class ReadWriteLockDatabaseComponent<Txn> extends DatabaseComponentImpl<Txn> {
try {
subscriptionLock.readLock().lock();
try {
- Txn txn = db.startTransaction();
+ T txn = db.startTransaction();
try {
anyAdded = storeMessages(txn, c, b.getMessages());
db.addBatchToAck(txn, c, b.getId());
@@ -819,7 +821,7 @@ class ReadWriteLockDatabaseComponent<Txn> extends DatabaseComponentImpl<Txn> {
try {
Collection<MessageId> offered = o.getMessageIds();
BitSet request = new BitSet(offered.size());
- Txn txn = db.startTransaction();
+ T txn = db.startTransaction();
try {
Iterator<MessageId> it = offered.iterator();
for(int i = 0; it.hasNext(); i++) {
@@ -857,7 +859,7 @@ class ReadWriteLockDatabaseComponent<Txn> extends DatabaseComponentImpl<Txn> {
if(!containsContact(c)) throw new NoSuchContactException();
subscriptionLock.writeLock().lock();
try {
- Txn txn = db.startTransaction();
+ T txn = db.startTransaction();
try {
Map<Group, Long> subs = s.getSubscriptions();
db.setSubscriptions(txn, c, subs, s.getTimestamp());
@@ -884,7 +886,7 @@ class ReadWriteLockDatabaseComponent<Txn> extends DatabaseComponentImpl<Txn> {
if(!containsContact(c)) throw new NoSuchContactException();
transportLock.writeLock().lock();
try {
- Txn txn = db.startTransaction();
+ T txn = db.startTransaction();
try {
Map<String, Map<String, String>> transports =
t.getTransports();
@@ -917,7 +919,7 @@ class ReadWriteLockDatabaseComponent<Txn> extends DatabaseComponentImpl<Txn> {
try {
transportLock.writeLock().lock();
try {
- Txn txn = db.startTransaction();
+ T txn = db.startTransaction();
try {
db.removeContact(txn, c);
db.commitTransaction(txn);
@@ -951,7 +953,7 @@ class ReadWriteLockDatabaseComponent<Txn> extends DatabaseComponentImpl<Txn> {
if(!containsContact(c)) throw new NoSuchContactException();
windowLock.writeLock().lock();
try {
- Txn txn = db.startTransaction();
+ T txn = db.startTransaction();
try {
db.setConnectionWindow(txn, c, transportId, w);
db.commitTransaction(txn);
@@ -971,7 +973,7 @@ class ReadWriteLockDatabaseComponent<Txn> extends DatabaseComponentImpl<Txn> {
try {
ratingLock.writeLock().lock();
try {
- Txn txn = db.startTransaction();
+ T txn = db.startTransaction();
try {
Rating old = db.setRating(txn, a, r);
// Update the sendability of the author's messages
@@ -997,7 +999,7 @@ class ReadWriteLockDatabaseComponent<Txn> extends DatabaseComponentImpl<Txn> {
boolean changed = false;
transportLock.writeLock().lock();
try {
- Txn txn = db.startTransaction();
+ T txn = db.startTransaction();
try {
Map<String, String> old = db.getTransportConfig(txn, name);
if(!config.equals(old)) {
@@ -1021,7 +1023,7 @@ class ReadWriteLockDatabaseComponent<Txn> extends DatabaseComponentImpl<Txn> {
boolean changed = false;
transportLock.writeLock().lock();
try {
- Txn txn = db.startTransaction();
+ T txn = db.startTransaction();
try {
Map<String, String> old = db.getTransports(txn).get(name);
if(!properties.equals(old)) {
@@ -1046,7 +1048,7 @@ class ReadWriteLockDatabaseComponent<Txn> extends DatabaseComponentImpl<Txn> {
try {
subscriptionLock.writeLock().lock();
try {
- Txn txn = db.startTransaction();
+ T txn = db.startTransaction();
try {
// Remove any ex-contacts from the set
Collection<ContactId> present =
@@ -1073,7 +1075,7 @@ class ReadWriteLockDatabaseComponent<Txn> extends DatabaseComponentImpl<Txn> {
boolean added = false;
subscriptionLock.writeLock().lock();
try {
- Txn txn = db.startTransaction();
+ T txn = db.startTransaction();
try {
if(db.containsSubscription(txn, g.getId())) {
db.addSubscription(txn, g);
@@ -1102,7 +1104,7 @@ class ReadWriteLockDatabaseComponent<Txn> extends DatabaseComponentImpl<Txn> {
try {
subscriptionLock.writeLock().lock();
try {
- Txn txn = db.startTransaction();
+ T txn = db.startTransaction();
try {
if(db.containsSubscription(txn, g)) {
db.removeSubscription(txn, g);