Examples of com.sleepycat.je.log.LogEntryType

com.sleepycat.je.log.LogEntryType

LogEntryType is an enumeration of all log entry types.

Log entries are versioned. When changing the persistent form of a log entry in any way that is incompatible with prior releases, make sure the LogEntry instance is capable of reading in older versions from the log and be sure to increment LOG_VERSION. The LogEntry.readEntry and Loggable.readFromLog methods should check the actual version of the entry. If it is less than LOG_VERSION, the old version should be converted to the current version.

Prior to LOG_VERSION 6, each log entry type had a separate version number that was incremented only when that log version changed. From LOG_VERSION 6 onward, all types use the same version, the LOG_VERSION constant. For versions prior to 6, the readEntry and readFromLog methods will be checking the old per-type version. There is no overlap between the old per-type versions and the LOG_VERSION values, because the per-type values are all below 6. [#15365]

The LogEntry instance must be sure that older versions are converted in memory into a correct instance of the newest version, so when that LogEntry object is written again as the result of migration, eviction, the resulting new log entry conforms to the requirements of the new version. If context objects are required for data conversion, the conversion can be done in the Node.postFetchInit method.

            new LNFileReader(env, readBufferSize, lastUsedLsn, 
                             false, endOfFileLsn, firstActiveLsn, null);


        Iterator iter = lnTypes.iterator();
        while (iter.hasNext()) {
            LogEntryType lnType = (LogEntryType) iter.next();
            reader.addTargetType(lnType);
        }


        Map countedFileSummaries = new HashMap(); // TxnNodeId -> file number
        Set countedAbortLsnNodes = new HashSet(); // set of TxnNodeId

            new LNFileReader(env, readBufferSize, rollForwardLsn,
                             true, DbLsn.NULL_LSN, endOfFileLsn, null);


        Iterator iter = lnTypes.iterator();
        while (iter.hasNext()) {
            LogEntryType lnType = (LogEntryType) iter.next();
            reader.addTargetType(lnType);
        }


        Set countedAbortLsnNodes = new HashSet(); // set of TxnNodeId

Examples of com.sleepycat.je.log.LogEntryType

Related Classes of com.sleepycat.je.log.LogEntryType