/**
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*/
package org.waveprotocol.wave.concurrencycontrol.common;
/**
* Listener for information about whether data has been acknowledged and
* committed by servers.
*
* A typical connection state:
* <pre>
* D = client delta
*
* acknowledged
* | | |
* v v v
* ---D-D---D---D------------D-D---D--D----------------> Time
* ^ ^ ^
* | | |
* commited in flight queue start
* </pre>
*
* @author jochen@google.com (Jochen Bekmann)
* @author zdwang@google.com (David Wang)
*/
public interface UnsavedDataListener {
/**
* Provides information about acknowledged and committed data.
*/
public interface UnsavedDataInfo {
/**
* Size of data sent but not yet acknowledged.
*/
int inFlightSize();
/**
* An estimate of the size of the total unacknowledged data: in flight data
* plus data accumulating waiting to be sent.
*/
int estimateUnacknowledgedSize();
/**
* An estimate of the size of the total uncommitted data: unacknowledged
* data plus acknowledged but not committed data.
*/
int estimateUncommittedSize();
/**
* Latest acknowledgement version.
*/
long laskAckVersion();
/**
* Latest commit version.
*/
long lastCommitVersion();
/**
* Calling this could be expensive due to stringification of data.
* Refrain from calling this constantly.
*
* @return A debug string about the unsaved data.
*/
String getInfo();
}
/**
* Called by the source of updates. Will not be called after onClose() was
* called.
*
* @param unsavedDataInfo information about data that's unsaved. This
* object is only valid during this method call. Invoking methods on
* this object after this call may give you incomplete data.
*/
void onUpdate(UnsavedDataInfo unsavedDataInfo);
/**
* Called when the resource has been closed. This removes the updater's entry
* in the listener.
*
* @param everythingCommitted true if all data on the server has been
* committed.
*/
void onClose(boolean everythingCommitted);
}