fedora.server.journal.readerwriter.multifile
Class LockingFollowingJournalReader

java.lang.Object
  fedora.server.journal.xmlhelpers.AbstractXmlReader
      fedora.server.journal.JournalReader
          fedora.server.journal.readerwriter.multifile.MultiFileJournalReader
              fedora.server.journal.readerwriter.multifile.LockingFollowingJournalReader

All Implemented Interfaces:

JournalConstants, MultiFileJournalConstants

public class LockingFollowingJournalReader
extends MultiFileJournalReader

Title: LockingFollowingJournalReader.java

Description: A Following Journal Reader that can be made quiescent by the presense of a lock file. This works like the MultiFileFollowingJournalReader, except that when looking for the next Journal file to be processed, it will take a moment to check the locking protocol. If a lock has been requested, it will accept the lock, and ignore any additional Journal files if present.

Polling continues, however. At each polling interval, the reader will check for the lock request. If the request has been removed, the lock acceptance will be removed also, and the reader will process the next Journal file, if one is found.

Version:

$Id: LockingFollowingJournalReader.java 5025 2006-09-01 22:08:17 +0000 (Fri, 01 Sep 2006) cwilper $

Author:

jblake@cs.cornell.edu

Field Summary

Fields inherited from class fedora.server.journal.readerwriter.multifile.MultiFileJournalReader

currentFile, open

Fields inherited from class fedora.server.journal.JournalReader

parameters, recoveryLog, role, server

Fields inherited from interface fedora.server.journal.readerwriter.multifile.MultiFileJournalConstants

DEFAULT_FOLLOW_POLLING_INTERVAL, PARAMETER_ARCHIVE_DIRECTORY, PARAMETER_FOLLOW_POLLING_INTERVAL, PARAMETER_JOURNAL_DIRECTORY, PARAMETER_LOCK_ACCEPTED_FILENAME, PARAMETER_LOCK_REQUESTED_FILENAME, PARAMETER_PAUSE_BEFORE_POLLING

Fields inherited from interface fedora.server.journal.JournalConstants

ARGUMENT_NAME_ALT_IDS, ARGUMENT_NAME_BDEF_PID, ARGUMENT_NAME_BINDING_MAP, ARGUMENT_NAME_BMECH_PID, ARGUMENT_NAME_CHECKSUM, ARGUMENT_NAME_CHECKSUM_TYPE, ARGUMENT_NAME_CONTEXT, ARGUMENT_NAME_CONTROL_GROUP, ARGUMENT_NAME_DISSEMINATOR_ID, ARGUMENT_NAME_DISSEMINATOR_LABEL, ARGUMENT_NAME_DISSEMINATOR_STATE, ARGUMENT_NAME_DS_CONTENT, ARGUMENT_NAME_DS_ID, ARGUMENT_NAME_DS_LABEL, ARGUMENT_NAME_DS_LOCATION, ARGUMENT_NAME_DS_STATE, ARGUMENT_NAME_ENCODING, ARGUMENT_NAME_END_DATE, ARGUMENT_NAME_FORCE, ARGUMENT_NAME_FORMAT, ARGUMENT_NAME_FORMAT_URI, ARGUMENT_NAME_IN, ARGUMENT_NAME_LABEL, ARGUMENT_NAME_LOCATION, ARGUMENT_NAME_LOG_MESSAGE, ARGUMENT_NAME_MIME_TYPE, ARGUMENT_NAME_NAMESPACE, ARGUMENT_NAME_NEW_PID, ARGUMENT_NAME_NUM_PIDS, ARGUMENT_NAME_OWNERID, ARGUMENT_NAME_PID, ARGUMENT_NAME_SERIALIZATION, ARGUMENT_NAME_START_DATE, ARGUMENT_NAME_STATE, ARGUMENT_NAME_VERSION_DATE, ARGUMENT_NAME_VERSIONABLE, ARGUMENT_TYPE_BINDING_MAP, ARGUMENT_TYPE_BOOLEAN, ARGUMENT_TYPE_DATE, ARGUMENT_TYPE_INTEGER, ARGUMENT_TYPE_NULL, ARGUMENT_TYPE_STREAM, ARGUMENT_TYPE_STRING, ARGUMENT_TYPE_STRINGARRAY, CONTEXT_MAPNAME_ACTION, CONTEXT_MAPNAME_ENVIRONMENT, CONTEXT_MAPNAME_RECOVERY, CONTEXT_MAPNAME_RESOURCE, CONTEXT_MAPNAME_SUBJECT, DEFAULT_AGE_LIMIT, DEFAULT_FILENAME_PREFIX, DEFAULT_SIZE_LIMIT, DOCUMENT_ENCODING, DOCUMENT_VERSION, FORMAT_JOURNAL_FILENAME_TIMESTAMP, METHOD_ADD_DATASTREAM, METHOD_ADD_DISSEMINATOR, METHOD_GET_NEXT_PID, METHOD_INGEST_OBJECT, METHOD_MODIFY_DATASTREAM_BY_REFERENCE, METHOD_MODIFY_DATASTREAM_BY_VALUE, METHOD_MODIFY_DISSEMINATOR, METHOD_MODIFY_OBJECT, METHOD_PURGE_DATASTREAM, METHOD_PURGE_DISSEMINATOR, METHOD_PURGE_OBJECT, METHOD_PUT_TEMP_STREAM, METHOD_SET_DATASTREAM_STATE, METHOD_SET_DATASTREAM_VERSIONABLE, METHOD_SET_DISSEMINATOR_STATE, PARAMETER_IGNORE_HASH, PARAMETER_JOURNAL_FILE_AGE_LIMIT, PARAMETER_JOURNAL_FILE_SIZE_LIMIT, PARAMETER_JOURNAL_FILENAME_PREFIX, PARAMETER_JOURNAL_MODE, PARAMETER_JOURNAL_READER_CLASSNAME, PARAMETER_JOURNAL_RECOVERY_LOG_CLASSNAME, PARAMETER_JOURNAL_WRITER_CLASSNAME, PARAMETER_RECOVERY_LOG_FILENAME, PARAMETER_RECOVERY_LOG_LEVEL, PASSWORD_CIPHER_TYPE, QNAME_ATTR_BIND_KEY_NAME, QNAME_ATTR_BIND_LABEL, QNAME_ATTR_CLIENT_IP, QNAME_ATTR_DATASTREAM_ID, QNAME_ATTR_DS_BIND_MAP_ID, QNAME_ATTR_DS_BIND_MAP_LABEL, QNAME_ATTR_DS_BIND_MECHANISM_PID, QNAME_ATTR_LOGIN_ID, QNAME_ATTR_METHOD, QNAME_ATTR_NAME, QNAME_ATTR_PASSWORD_TYPE, QNAME_ATTR_REPOSITORY_HASH, QNAME_ATTR_SEQ_NO, QNAME_ATTR_STATE, QNAME_ATTR_TIMESTAMP, QNAME_ATTR_TYPE, QNAME_ATTR_USERID, QNAME_TAG_ARGUMENT, QNAME_TAG_ARRAYELEMENT, QNAME_TAG_CONTEXT, QNAME_TAG_DS_BINDING, QNAME_TAG_DS_BINDING_MAP, QNAME_TAG_JOURNAL, QNAME_TAG_JOURNAL_ENTRY, QNAME_TAG_MULTI_VALUE_MAP, QNAME_TAG_MULTI_VALUE_MAP_KEY, QNAME_TAG_MULTI_VALUE_MAP_VALUE, QNAME_TAG_NOOP, QNAME_TAG_NOW, QNAME_TAG_PASSWORD, SYSTEM_PROPERTY_PREFIX, TIMESTAMP_FORMAT, VALUE_FALSE, VALUE_JOURNAL_MODE_NORMAL, VALUE_JOURNAL_MODE_RECOVER, VALUE_RECOVERY_LOG_LEVEL_HIGH, VALUE_RECOVERY_LOG_LEVEL_LOW, VALUE_RECOVERY_LOG_LEVEL_MEDIUM, VALUE_TRUE

Constructor Summary

LockingFollowingJournalReader(java.util.Map<java.lang.String,java.lang.String> parameters, java.lang.String role, JournalRecoveryLog recoveryLog, ServerInterface server)
Require parameters for polling interval, lock request filename and lock acceptance filename.

Method Summary

protected fedora.server.journal.readerwriter.multifile.JournalInputFile	openNextFile() Process the locking mechanism.
void	shutdown() If the server requests a shutdown, stop waiting the next file to come in.

Methods inherited from class fedora.server.journal.readerwriter.multifile.MultiFileJournalReader

readJournalEntry, toString

Methods inherited from class fedora.server.journal.JournalReader

checkRepositoryHash, getInstance, readJournalEntry

Methods inherited from class fedora.server.journal.xmlhelpers.AbstractXmlReader

advancePastWhitespace, getNotCharactersException, getNotEndTagException, getNotNextMemberOrEndOfGroupException, getNotStartTagException, getOptionalAttributeValue, getRequiredAttributeValue, isEndTagEvent, isStartTagEvent, readCharactersUntilEndTag, readStartTag

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

LockingFollowingJournalReader

public LockingFollowingJournalReader(java.util.Map<java.lang.String,java.lang.String> parameters,
                                     java.lang.String role,
                                     JournalRecoveryLog recoveryLog,
                                     ServerInterface server)
                              throws JournalException

Require parameters for polling interval, lock request filename and lock acceptance filename.

Throws:

JournalException

Method Detail

openNextFile

protected fedora.server.journal.readerwriter.multifile.JournalInputFile openNextFile()
                                                                              throws JournalException

Process the locking mechanism. If we are not locked, we should look for another journal file to process. Ask for a new file, using the superclass method, but if none is found, wait for a while and repeat. This will continue until we get a server shutdown signal.

Overrides:

openNextFile in class MultiFileJournalReader

Throws:

JournalException

shutdown

public void shutdown()
              throws JournalException

If the server requests a shutdown, stop waiting the next file to come in.

Overrides:

shutdown in class MultiFileJournalReader

Throws:

JournalException