Author: norman
Date: Mon Feb 7 07:15:54 2011
New Revision: 1067867
URL: http://svn.apache.org/viewvc?rev=1067867&view=rev
Log:
Share the UidToMsnConverter between MailboxSession's to reduce memory usage.
See IMAP-255
Modified:
james/imap/trunk/processor/src/main/java/org/apache/james/imap/processor/AbstractSelectionProcessor.java
james/imap/trunk/processor/src/main/java/org/apache/james/imap/processor/base/SelectedMailboxImpl.java
james/imap/trunk/processor/src/main/java/org/apache/james/imap/processor/base/UidToMsnConverter.java
Modified:
james/imap/trunk/processor/src/main/java/org/apache/james/imap/processor/AbstractSelectionProcessor.java
URL:
http://svn.apache.org/viewvc/james/imap/trunk/processor/src/main/java/org/apache/james/imap/processor/AbstractSelectionProcessor.java?rev=1067867&r1=1067866&r2=1067867&view=diff
==============================================================================
---
james/imap/trunk/processor/src/main/java/org/apache/james/imap/processor/AbstractSelectionProcessor.java
(original)
+++
james/imap/trunk/processor/src/main/java/org/apache/james/imap/processor/AbstractSelectionProcessor.java
Mon Feb 7 07:15:54 2011
@@ -19,7 +19,6 @@
package org.apache.james.imap.processor;
-import java.util.Iterator;
import java.util.List;
import javax.mail.Flags;
@@ -28,8 +27,8 @@ import org.apache.james.imap.api.ImapCom
import org.apache.james.imap.api.ImapSessionUtils;
import org.apache.james.imap.api.display.HumanReadableText;
import org.apache.james.imap.api.message.response.StatusResponse;
-import org.apache.james.imap.api.message.response.StatusResponseFactory;
import org.apache.james.imap.api.message.response.StatusResponse.ResponseCode;
+import org.apache.james.imap.api.message.response.StatusResponseFactory;
import org.apache.james.imap.api.process.ImapProcessor;
import org.apache.james.imap.api.process.ImapSession;
import org.apache.james.imap.api.process.SelectedMailbox;
@@ -44,7 +43,6 @@ import org.apache.james.mailbox.MailboxN
import org.apache.james.mailbox.MailboxPath;
import org.apache.james.mailbox.MailboxSession;
import org.apache.james.mailbox.MessageManager;
-import org.apache.james.mailbox.SearchQuery;
import org.apache.james.mailbox.MessageManager.MetaData;
abstract class AbstractSelectionProcessor<M extends
AbstractMailboxSelectionRequest> extends AbstractMailboxProcessor<M> {
@@ -197,14 +195,9 @@ abstract class AbstractSelectionProcesso
private SelectedMailbox createNewSelectedMailbox(final MessageManager
mailbox,
final MailboxSession mailboxSession, ImapSession session,
MailboxPath path)
throws MailboxException {
- SearchQuery query = new SearchQuery();
- query.andCriteria(SearchQuery.all());
-
- // use search here to allow implementation a better way to improve
selects on mailboxes.
- // See https://issues.apache.org/jira/browse/IMAP-192
- final Iterator<Long> it = mailbox.search(query, mailboxSession);
+
- final SelectedMailbox sessionMailbox = new
SelectedMailboxImpl(getMailboxManager(), it, mailboxSession, path);
+ final SelectedMailbox sessionMailbox = new
SelectedMailboxImpl(getMailboxManager(), mailboxSession, path);
session.selected(sessionMailbox);
return sessionMailbox;
}
Modified:
james/imap/trunk/processor/src/main/java/org/apache/james/imap/processor/base/SelectedMailboxImpl.java
URL:
http://svn.apache.org/viewvc/james/imap/trunk/processor/src/main/java/org/apache/james/imap/processor/base/SelectedMailboxImpl.java?rev=1067867&r1=1067866&r2=1067867&view=diff
==============================================================================
---
james/imap/trunk/processor/src/main/java/org/apache/james/imap/processor/base/SelectedMailboxImpl.java
(original)
+++
james/imap/trunk/processor/src/main/java/org/apache/james/imap/processor/base/SelectedMailboxImpl.java
Mon Feb 7 07:15:54 2011
@@ -21,7 +21,6 @@ package org.apache.james.imap.processor.
import java.util.ArrayList;
import java.util.Collection;
-import java.util.Iterator;
import java.util.Set;
import java.util.TreeSet;
@@ -45,7 +44,7 @@ public class SelectedMailboxImpl impleme
private boolean recentUidRemoved;
- public SelectedMailboxImpl(final MailboxManager mailboxManager, final
Iterator<Long> uids,
+ public SelectedMailboxImpl(final MailboxManager mailboxManager,
final MailboxSession mailboxSession, final MailboxPath path)
throws MailboxException {
recentUids = new TreeSet<Long>();
recentUidRemoved = false;
@@ -54,8 +53,7 @@ public class SelectedMailboxImpl impleme
// Ignore events from our session
events.setSilentFlagChanges(true);
mailboxManager.addListener(path, events, mailboxSession);
- converter = new UidToMsnConverter(uids);
- mailboxManager.addListener(path, converter, mailboxSession);
+ converter = UidToMsnConverter.get(mailboxManager, path,
mailboxSession);
}
/**
Modified:
james/imap/trunk/processor/src/main/java/org/apache/james/imap/processor/base/UidToMsnConverter.java
URL:
http://svn.apache.org/viewvc/james/imap/trunk/processor/src/main/java/org/apache/james/imap/processor/base/UidToMsnConverter.java?rev=1067867&r1=1067866&r2=1067867&view=diff
==============================================================================
---
james/imap/trunk/processor/src/main/java/org/apache/james/imap/processor/base/UidToMsnConverter.java
(original)
+++
james/imap/trunk/processor/src/main/java/org/apache/james/imap/processor/base/UidToMsnConverter.java
Mon Feb 7 07:15:54 2011
@@ -20,22 +20,35 @@
package org.apache.james.imap.processor.base;
import java.util.ArrayList;
+import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
+import java.util.Map;
import java.util.SortedMap;
import java.util.TreeMap;
+import java.util.concurrent.atomic.AtomicInteger;
+
import org.apache.james.imap.api.process.SelectedMailbox;
+import org.apache.james.mailbox.MailboxException;
import org.apache.james.mailbox.MailboxListener;
+import org.apache.james.mailbox.MailboxManager;
+import org.apache.james.mailbox.MailboxPath;
+import org.apache.james.mailbox.MailboxSession;
+import org.apache.james.mailbox.MessageManager;
+import org.apache.james.mailbox.SearchQuery;
/**
- * {@link MailboxListener} which takes care of maintaining a mapping between
message uids and msn (index)
+ * {@link UidToMsnConverter} takes care of maintaining a mapping between
message uids and msn (index) by register a {@link MailboxListener} for a {@link
MailboxPath}
+ *
+ * See {@link UidToMsnConverter} is shared across different {@link
MailboxSession}'s for the same {@link MailboxPath} to reduce memory usage. See
IMAP-255
*
*
- * TODO: This is a major memory hog
- * TODO: Each concurrent session requires one, and typical clients now open
many
*/
-public class UidToMsnConverter implements MailboxListener {
+public class UidToMsnConverter {
+ // Hold all cached UidToMsnConverter
+ private final static Map<MailboxPath, UidToMsnConverter> converters = new
HashMap<MailboxPath, UidToMsnConverter>();
+
private SortedMap<Integer, Long> msnToUid;
private SortedMap<Long, Integer> uidToMsn;
@@ -44,9 +57,87 @@ public class UidToMsnConverter implement
private int highestMsn = 0;
- private boolean closed = false;
+ // hold the reference count for a shared UidToMsnConverter
+ private AtomicInteger references = new AtomicInteger(0);
+
+ /**
+ * Return a instance of the {@link UidToMsnConverter} which can be a new
one or a shared if there is already a {@link UidToMsnConverter} for the given
+ * {@link MailboxPath}.
+ *
+ * @param manager
+ * @param path
+ * @param session
+ * @return converter
+ * @throws MailboxException
+ */
+ public static UidToMsnConverter get(MailboxManager manager, MailboxPath
path, MailboxSession session) throws MailboxException {
+ boolean found = false;
+ UidToMsnConverter converter = null;
+
+ // see if we have a converter for the path
+ synchronized (converters) {
+ converter = converters.get(path);
+ if (converter == null) {
+ converter = new UidToMsnConverter();
+ converters.put(path, converter);
+ } else {
+ found = true;
+ }
+ }
+
+ // now be sure we only return the converter if the one which exists is
init. So to be sure we synchronize on it
+ synchronized (converter) {
+ final UidToMsnConverter c = converter;
+ // the converter was not found before so we need to init it to get
a list of all uids
+ if (!found) {
+ converter.init(manager.getMailbox(path, session), session);
+ manager.addListener(path, new MailboxListener() {
+
+ /*
+ * (non-Javadoc)
+ * @see org.apache.james.mailbox.MailboxListener#isClosed()
+ */
+ public synchronized boolean isClosed() {
+ return c.references.get() < 1;
+ }
+
+ /*
+ * (non-Javadoc)
+ * @see
org.apache.james.mailbox.MailboxListener#event(org.apache.james.mailbox.MailboxListener.Event)
+ */
+ public void event(Event event) {
+ if (event instanceof MessageEvent) {
+ final MessageEvent messageEvent = (MessageEvent)
event;
+ final long uid = messageEvent.getSubjectUid();
+ if (event instanceof Added) {
+ c.add(uid);
+ }
+
+ }
+ }
+ }, session);
+ }
+
+ // increment the reference count so can handle the close
operations in the right manner
+ converter.references.incrementAndGet();
+ return converter;
+ }
+
+ }
+
+ // Should only get accessed throw the static factory method
+ private UidToMsnConverter() {
+ }
+
+ private void init(MessageManager mailbox, MailboxSession mailboxSession)
throws MailboxException {
+ SearchQuery query = new SearchQuery();
+ query.andCriteria(SearchQuery.all());
+
+ // use search here to allow implementation a better way to improve
+ // selects on mailboxes.
+ // See https://issues.apache.org/jira/browse/IMAP-192
+ final Iterator<Long> uids = mailbox.search(query, mailboxSession);
- public UidToMsnConverter(final Iterator<Long> uids) {
msnToUid = new TreeMap<Integer, Long>();
uidToMsn = new TreeMap<Long, Integer>();
if (uids != null) {
@@ -57,7 +148,7 @@ public class UidToMsnConverter implement
highestMsn = msn;
msnToUid.put(msn, uid);
uidToMsn.put(uid, msn);
-
+
msn++;
}
@@ -137,18 +228,7 @@ public class UidToMsnConverter implement
}
}
- /**
- * @see
org.apache.james.mailbox.MailboxListener#event(org.apache.james.mailbox.MailboxListener.Event)
- */
- public synchronized void event(Event event) {
- if (event instanceof MessageEvent) {
- final MessageEvent messageEvent = (MessageEvent) event;
- final long uid = messageEvent.getSubjectUid();
- if (event instanceof Added) {
- add(uid);
- }
- }
- }
+
/**
@@ -177,16 +257,11 @@ public class UidToMsnConverter implement
* Close this {@link MailboxListener} and dispose all stored stuff
*/
public synchronized void close() {
- uidToMsn.clear();
- msnToUid.clear();
- closed = true;
+ if (references.incrementAndGet() == 0) {
+ uidToMsn.clear();
+ msnToUid.clear();
+ }
}
- /*
- * (non-Javadoc)
- * @see org.apache.james.mailbox.MailboxListener#isClosed()
- */
- public synchronized boolean isClosed() {
- return closed;
- }
+
}
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
