com.sap.tc.logging.reader

Class ReadableLog

java.lang.Object
  com.sap.tc.logging.ExceptionHandling
      com.sap.tc.logging.Log
          com.sap.tc.logging.StreamLog
              com.sap.tc.logging.FileLog
                  com.sap.tc.logging.reader.ReadableLog

All Implemented Interfaces:

Cloneable, IFileLog, ILog, IObjectInfo, IReadableLog

public class ReadableLog

extends FileLog

implements IReadableLog

Defines common operations to read log messages (a message record) from a log destination. Currently, this mainly handles sequential records retrieval starting either from the oldest or latest time point. To avoid messing up the sequential reading from concurrent readers on the same log destination, it is recommended to get a copy of this 'readable' log for each reader.

Field Summary

Fields inherited from class com.sap.tc.logging.FileLog

DEF_LIMIT, MODE_FILE_SET, MODE_MAX, MODE_MIN, MODE_SINGLE_FILE, NO_CNT, NO_LIMIT

Fields inherited from class com.sap.tc.logging.Log

LOG_ACCESSABILITY_TYPE_LOCAL_LOG, LOG_ACCESSABILITY_TYPE_NORMAL_LOG, LOG_ACCESSABILITY_TYPE_PRIVATE_LOG, STATUS_CLOSED, STATUS_INVALID, STATUS_OPENED

Fields inherited from class com.sap.tc.logging.ExceptionHandling

EX_NO_FILTER_EMSG, EX_NO_FORMATTER_EMSG, EX_NO_INSTANCE_EMSG

Constructor Summary

ReadableLog(String pattern)
Deprecated. ReadableLog become factory class. Use factory methods: - createReadableLog(FileLog fileLog) to get old IReadableLog instance - createFileReadLog(FileLog fileLog) to get new IReadLog instance for reading Files written using ListFormatter and TraceFormatter

Method Summary

boolean	areLoggingAttributesEditable() This method verifies whether the attributes like severity can be set.
protected Object	clone()
void	close() Closes output of this log object.
static IReadLog	createFileReadLog(FileLog fileLog) Deprecated. Not suported
static IReadLog	createFileReadLog(String fileName) Create FileReadLog object.
IReadableLog	createReadableLog() Create a 'copy' of this Filelog, exposing only the message reading API.
static IReadableLog	createReadableLog(FileLog fileLog) Create a 'copy' of this Filelog, exposing only the message reading API.
String	getFileBeingCurrentlyRead() This method returns the name of the file that is being currently read.
long	getFilePointer() This returns the file pointer.
long	getLastModified()
ILoggingResultSet	getNextMatch(String[] searchTokens) This method returns LoggingResultSet that contains one or zero LogRecords.
ILoggingResultSet	getNextMatch(String[] searchTokens, boolean ignoreCase) This method returns LoggingResultSet that contains one or zero LogRecords.
ILoggingResultSet	getPreviousMatch(String[] searchTokens) This method returns LoggingResultSet that contains one or zero LogRecords.
ILoggingResultSet	getPreviousMatch(String[] searchTokens, boolean ignoreCase) This method returns LoggingResultSet that contains one or zero LogRecords.
long	length() Deprecated. Use getFileLenght()
void	open() Closes output of this log object.
ILoggingResultSet	readLatestMsgRecords(int numberOfRecords) Retrieve the latest n messages and return them in a result set in chronological order.
ArrayList	readLatestRecords(int numMsg) Deprecated. Resulting logrecords do not indicate status which is not good enough for complicated scenario like logfile rotation. It will kept around for a while, but will be eventually replaced by readLatestMsgRecords(int).
ILoggingResultSet	readNextMsgRecords(int numberOfRecords) Continue retrieving x relatively newer messages, picked from the point where the last message read from the previous read operation, with respect to the direction of the previous read operation.
ArrayList	readNextRecords(int numMsg) Deprecated. Resulting logrecords do not indicate status which is not good enough for complicated scenario like logfile rotation. It will kept around for a while, but will be eventually replaced by readNextMsgRecords(int).
ILoggingResultSet	readOldestMsgRecords(int numberOfRecords) Retrieve the oldest n messages and return them in a result set in chronological order.
ArrayList	readOldestRecords(int numMsg) Deprecated. Resulting logrecords do not indicate status which is not good enough for complicated scenario like logfile rotation. It will kept around for a while, but will be eventually replaced by readOldestMsgRecords(int).
ILoggingResultSet	readPrevMsgRecords(int numberOfRecords) Continue retrieving x relatively older messages, picked from the point where the last message read from the previous read operation, with respect to the direction of the previous read operation.
ArrayList	readPrevRecords(int numMsg) Deprecated. Resulting logrecords do not indicate status which is not good enough for complicated scenario like logfile rotation. It will kept around for a while, but will be eventually replaced by readPrevMsgRecords(int).
void	seek(long filePointer) Tries to set the file pointer specified by the parameter.
void	setFormatter(Formatter formatter) Sets the formatter that dictates the format of log records in this log.
int	status() Status of this log object.

Methods inherited from class com.sap.tc.logging.FileLog

calculateFileNames, calculateFileNames, equals, equalsPattern, expandPattern, expandPattern, expandPattern, findBeginningOfFileSet, findEndOfFileSet, getCnt, getFileCurrentlyBeingWritten, getFileLength, getFileName, getFileNamePattern, getFilePathPattern, getIndex, getLimit, getLogId, getMode, getParent, getParentFile, getPath, getPattern, isAppend, resetInt, setAppend, setCnt, setFormatterInt, setIndex, setLimit, setMode, setPattern, setRotation, writeInt, writeLogFooter, writeLogHeader

Methods inherited from class com.sap.tc.logging.StreamLog

closeInt, flushInt, getEncoding, getOutputStream, openInt, setEncoding

Methods inherited from class com.sap.tc.logging.Log

addFilter, addOwner, beGroup, beLogged, finalize, flush, getDescription, getEffectiveSeverity, getFilters, getFooter, getFormatter, getHeader, getLocalLogOwner, getLoggedCount, getLogName, getLogTypeAccessibility, getName, getNumberOfLogRecordsWritten, getOwners, getRecord, getVerInUse, isAutoFlush, isClosed, isFiltersAgreeing, isHeaderWritten, isOpened, isSuppressing, removeFilter, removeFilters, removeOwner, reset, resetLoggedCount, setAutoFlush, setDescription, setEffectiveSeverity, setFooter, setHeader, setHeaderWritten, setLocalLogOwner, setLogName, setLogTypeAccessibility, setName, setSize, setStatus, setSuppressing, setVerInUse, size, write, writeInt

Methods inherited from class com.sap.tc.logging.ExceptionHandling

getException, getExceptions, handleException, handleException, resetException, throwException

Methods inherited from class java.lang.Object

getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface com.sap.tc.logging.interfaces.IReadableLog

getLogId

Methods inherited from interface com.sap.tc.logging.interfaces.IFileLog

getCnt, getFileLength, getFileName, getLimit, getParent, getPath, getPattern, isAppend

Methods inherited from interface com.sap.tc.logging.interfaces.ILog

addFilter, beLogged, flush, getEffectiveSeverity, getEncoding, getFilters, getFooter, getFormatter, getHeader, getLogTypeAccessibility, getNumberOfLogRecordsWritten, isAutoFlush, isClosed, isOpened, removeFilter, removeFilters, setAutoFlush, setEffectiveSeverity, setEncoding, setLogTypeAccessibility

Methods inherited from interface com.sap.tc.logging.interfaces.IObjectInfo

getDescription, getName, getVerInUse

Constructor Detail

ReadableLog

public ReadableLog(String pattern)

Deprecated. ReadableLog become factory class. Use factory methods: - createReadableLog(FileLog fileLog) to get old IReadableLog instance - createFileReadLog(FileLog fileLog) to get new IReadLog instance for reading Files written using ListFormatter and TraceFormatter

Method Detail

createFileReadLog

public static IReadLog createFileReadLog(FileLog fileLog)

Deprecated. Not suported

This method log all exception but doesn't re-throw it out.

createFileReadLog

public static IReadLog createFileReadLog(String fileName)
                                  throws FileDataException

Create FileReadLog object. Note: This method may be used only on log files which contains the file log header data.

Parameters:

fileName -

Returns:

Instance of FileReadLog

Throws:

FileDataException

createReadableLog

public static IReadableLog createReadableLog(FileLog fileLog)

Create a 'copy' of this Filelog, exposing only the message reading API. Then, retrieval of message records for each reader will be independent. This can avoid messing up the sequential reading pointers from potential concurrent multiple readers.

Returns:

A copy of this readable log that contains mainly cursor actions or a null value if creation fails

createReadableLog

public IReadableLog createReadableLog()

Create a 'copy' of this Filelog, exposing only the message reading API. Then, retrieval of message records for each reader will be independent. This can avoid messing up the sequential reading pointers from potential concurrent multiple readers.

Specified by:

createReadableLog in interface IReadableLog

Returns:

A copy of this readable log that contains mainly cursor actions or a null value if creation fails

readLatestMsgRecords

public ILoggingResultSet readLatestMsgRecords(int numberOfRecords)
                                       throws IllegalArgumentException,
                                              UnsupportedFormatException,
                                              FileNotFoundException,
                                              SecurityException,
                                              IOException

Retrieve the latest n messages and return them in a result set in chronological order. This method always refers to the newest messages even the output file is growing and rotating.

Specified by:

readLatestMsgRecords in interface IReadableLog

Parameters:

numberOfRecords - Number of messages (>0) to be retrieved

Returns:

retrieved messages packed in LogRecord in chronological order, stored in a list of the result set, with position [0] holding the oldest of the resulting messages.
The resulting list contains all valid available messages, that is, the size may be smaller than the requested number. This can happen if there actually exists fewer messages in the file, including empty file (status valid), or certain messages are getting parsing error (status invalid).
If file is not empty but no valid message can be retrieved, this will return an empty list with status invalid.

Throws:

IllegalArgumentException - Negative number or zero messages requested

UnsupportedFormatException - Formatter type not supported by Log Viewer

FileNotFoundException - Output file not found

SecurityException - Access to output file denied

IOException - Problem reading data from output file

See Also:

LoggingResultSet

readOldestMsgRecords

public ILoggingResultSet readOldestMsgRecords(int numberOfRecords)
                                       throws IllegalArgumentException,
                                              UnsupportedFormatException,
                                              FileNotFoundException,
                                              SecurityException,
                                              IOException

Retrieve the oldest n messages and return them in a result set in chronological order. This method always refers to the currently available oldest messages which may be different due to the rotating feature from the constantly growing output file size.

Specified by:

readOldestMsgRecords in interface IReadableLog

Parameters:

numberOfRecords - Number of messages (>0) to be retrieved

Returns:

retrieved messages packed in LogRecord in chronological order, stored in a list of the result set, with position [0] holding the oldest of the resulting messages.
The resulting list contains all valid available messages, that is, the size may be smaller than the requested number. This can happen if there actually exists fewer messages in the file, including empty file (status valid), or certain messages are getting parsing error (status invalid).
If file is not empty but no valid message can be retrieved, this will return an empty list with status invalid.

Throws:

IllegalArgumentException - Negative number or zero messages requested

UnsupportedFormatException - Formatter type not supported by Log Viewer

FileNotFoundException - Output file not found

SecurityException - Access to output file denied

IOException - Problem reading data from output file

See Also:

LoggingResultSet

readPrevMsgRecords

public ILoggingResultSet readPrevMsgRecords(int numberOfRecords)
                                     throws IllegalArgumentException,
                                            UnsupportedFormatException,
                                            FileNotFoundException,
                                            SecurityException,
                                            IOException

Continue retrieving x relatively older messages, picked from the point where the last message read from the previous read operation, with respect to the direction of the previous read operation. For example, if previous call is readLatestMsgRecords(5), this call readPrevMsgRecords(2) will retrieve the 7th and 6th lastest messages. If previous call is readOldestMsgRecords(5), this call readPrevMsgRecords(2) will retrieve the 3rd & 4th oldest messages.

If this method is called without a prior call to readLatestMsgRecords(int) or readOldestMsgRecords(int), this will behave the same as calling readLatestMsgRecords(numMsg) .

Messages are returned in a result set in chronological order. Due to the potential file overwriting by the rotating feature, the file being currently referenced to may no longer exist and thus data will become invalid. It is always a good idea to check the overall status of the result set before getting the resulting list.

Specified by:

readPrevMsgRecords in interface IReadableLog

Parameters:

numberOfRecords - Number of messages(>0) to be retrieved

Returns:

retrieved messages packed in LogRecord in chronological order, stored in a list of the result set, with position [0] holding the oldest of the resulting messages. Due to the potential rotating feature, you are advised to check the overall status of the result set (isValid()) before retrieving the resulting list.
The resulting list contains all valid available messages, that is, the size may be smaller than the requested number. This can happen if there actually exists fewer messages in the file (status valid), or certain messages are getting parsing error (status invalid).
If no more older message can be retrieved, this will return a valid empty list in the result set. If current file is being overwritten while reading, status set to invalid in result set.

Throws:

IllegalArgumentException - Negative number or zero messages requested

UnsupportedFormatException - Formatter type not supported by Log Viewer

FileNotFoundException - Output file not found

SecurityException - Access to output file denied

IOException - Problem reading data from output file

See Also:

LoggingResultSet, FileLog.LogRecordResultSet

readNextMsgRecords

public ILoggingResultSet readNextMsgRecords(int numberOfRecords)
                                     throws IllegalArgumentException,
                                            UnsupportedFormatException,
                                            FileNotFoundException,
                                            SecurityException,
                                            IOException

Continue retrieving x relatively newer messages, picked from the point where the last message read from the previous read operation, with respect to the direction of the previous read operation. For example, if previous call is readOldestMsgRecords(5), this call readNextMsgRecords(2) will retrieve the 6th and 7th oldest messages. If previous call is readLatestMsgRecords(5), this call readNextMsgRecords(2) will retrieve the 4th & 3rd lastest messages.

If this method is called without a prior call to readLatestMsgRecords(int) or readOldestMsgRecords(int), this will behave the same as calling readOldestMsgRecords(numMsg) .

Messages are returned in a result set in chronological order. Due to the potential file overwriting by the rotating feature, the file being currently referenced to may no longer exist and thus data will become invalid. It is always a good idea to check the overall status of the result set before getting the resulting list.

Specified by:

readNextMsgRecords in interface IReadableLog

Parameters:

numberOfRecords - Number of messages(>0) to be retrieved

Returns:

retrieved messages packed in LogRecord in chronological order, stored in a list of the result set, with position [0] holding the oldest of the resulting messages. Due to the potential rotating feature, you are advised to check the overall status of the result set (isValid()) before retrieving the resulting list.
The resulting list contains all valid available messages, that is, the size may be smaller than the requested number. This can happen if there actually exists fewer messages in the file (status valid), or certain messages are getting parsing error (status invalid).
If no more newer message can be retrieved, this will return a valid empty list in the result set. If current file is being overwritten while reading, status set to invalid in result set.

Throws:

IllegalArgumentException - Negative number or zero messages requested

UnsupportedFormatException - Formatter type not supported by Log Viewer

FileNotFoundException - Output file not found

SecurityException - Access to output file denied

IOException - Problem reading data from output file

See Also:

LoggingResultSet, FileLog.LogRecordResultSet

getNextMatch

public ILoggingResultSet getNextMatch(String[] searchTokens)
                               throws IllegalArgumentException,
                                      UnsupportedFormatException,
                                      FileNotFoundException,
                                      SecurityException,
                                      IOException

This method returns LoggingResultSet that contains one or zero LogRecords. If the search is successful, there will be one LogRecord. If not, there will be zero records. It takes an array of strings that need to be searched. For now, the first string in the array is the only one to be searched for (August 8, 2003). In future, searching for multiple strings will be supported.

Specified by:

getNextMatch in interface IReadableLog

Parameters:

searchTokens -

Returns:

A LoggingResultSet of matching LogRecord.

Throws:

IllegalArgumentException

UnsupportedFormatException

IOException

FileNotFoundException

SecurityException

getNextMatch

public ILoggingResultSet getNextMatch(String[] searchTokens,
                                      boolean ignoreCase)
                               throws IllegalArgumentException,
                                      UnsupportedFormatException,
                                      FileNotFoundException,
                                      SecurityException,
                                      IOException

This method returns LoggingResultSet that contains one or zero LogRecords. If the search is successful, there will be one LogRecord. If not, there will be zero records. It takes an array of strings that need to be searched. For now, the first string in the array is the only one to be searched for (August 8, 2003). In future, searching for multiple strings will be supported. If ignoreCase is true, it will search for the searchTokens without paying attention to case.

Specified by:

getNextMatch in interface IReadableLog

Parameters:

searchTokens -

ignoreCase -

Returns:

A LoggingResultSet of matching LogRecord.

Throws:

IllegalArgumentException

UnsupportedFormatException

IOException

FileNotFoundException

SecurityException

getPreviousMatch

public ILoggingResultSet getPreviousMatch(String[] searchTokens)
                                   throws IllegalArgumentException,
                                          UnsupportedFormatException,
                                          FileNotFoundException,
                                          SecurityException,
                                          IOException

This method returns LoggingResultSet that contains one or zero LogRecords. If the search is successful, there will be one LogRecord. If not, there will be zero records. It takes an array of strings that need to be searched. For now, the first string in the array is the only one to be searched for (August 8, 2003). In future, searching for multiple strings will be supported.

Specified by:

getPreviousMatch in interface IReadableLog

Parameters:

searchTokens -

Returns:

A LoggingResultSet of matching LogRecord.

Throws:

IllegalArgumentException

UnsupportedFormatException

IOException

FileNotFoundException

SecurityException

getPreviousMatch

public ILoggingResultSet getPreviousMatch(String[] searchTokens,
                                          boolean ignoreCase)
                                   throws IllegalArgumentException,
                                          UnsupportedFormatException,
                                          FileNotFoundException,
                                          SecurityException,
                                          IOException

This method returns LoggingResultSet that contains one or zero LogRecords. If the search is successful, there will be one LogRecord. If not, there will be zero records. It takes an array of strings that need to be searched. For now, the first string in the array is the only one to be searched for (August 8, 2003). In future, searching for multiple strings will be supported. If ignoreCase is true, it will search for the searchTokens without paying attention to case.

Specified by:

getPreviousMatch in interface IReadableLog

Parameters:

searchTokens -

ignoreCase -

Returns:

A LoggingResultSet of matching LogRecord.

Throws:

IllegalArgumentException

UnsupportedFormatException

IOException

FileNotFoundException

SecurityException

areLoggingAttributesEditable

public boolean areLoggingAttributesEditable()

This method verifies whether the attributes like severity can be set.

Specified by:

areLoggingAttributesEditable in interface IReadableLog

Returns:

boolean true if the attributes can be set and false otherwise.

getFileBeingCurrentlyRead

public String getFileBeingCurrentlyRead()

This method returns the name of the file that is being currently read. If the file name is empty, it tries to locate the oldest file. It does not check whether or not the file really exists.

Returns:

The name of the file currently being read.

getFilePointer

public long getFilePointer()
                    throws IOException

This returns the file pointer.

Returns:

-1 if currentFileReader equals null or current file pointer if currentFileReader exists.

Throws:

IOException

seek

public void seek(long filePointer)
          throws IOException

Tries to set the file pointer specified by the parameter. If currentFileReader is null, it throws RuntimeException.

Parameters:

filePointer -

Throws:

IOException

getLastModified

public long getLastModified()
                     throws IOException

Specified by:

getLastModified in interface IReadableLog

Throws:

IOException

status

public int status()

Description copied from interface: ILog

Status of this log object.

Specified by:

status in interface ILog

Overrides:

status in class Log

open

public void open()

Closes output of this log object.

Specified by:

open in interface ILog

Overrides:

open in class Log

close

public void close()

Closes output of this log object.

Specified by:

close in interface ILog

Overrides:

close in class Log

setFormatter

public void setFormatter(Formatter formatter)

Sets the formatter that dictates the format of log records in this log. Note: If you send a null like argument the default formater (ListFormatter), will be created.

Specified by:

setFormatter in interface ILog

Overrides:

setFormatter in class FileLog

Returns:

Formatter

See Also:

Log.getFormatter()

clone

protected Object clone()
                throws CloneNotSupportedException

Overrides:

clone in class FileLog

Throws:

CloneNotSupportedException

readLatestRecords

public ArrayList readLatestRecords(int numMsg)
                            throws IllegalArgumentException,
                                   UnsupportedFormatException,
                                   IOException

Deprecated. Resulting logrecords do not indicate status which is not good enough for complicated scenario like logfile rotation. It will kept around for a while, but will be eventually replaced by readLatestMsgRecords(int).

Retrieve the latest n messages and return them in an array list. This method always refers to the newest messages even the output file is growing.

Specified by:

readLatestRecords in interface IReadableLog

Parameters:

numMsg - Number of messages (>0) to be retrieved

Returns:

Each retrieved message packed in an array list.

Throws:

UnsupportedFormatException

IllegalArgumentException - Negative number or zero messages requested

IOException - Problem reading data from output file

readOldestRecords

public ArrayList readOldestRecords(int numMsg)
                            throws IllegalArgumentException,
                                   UnsupportedFormatException,
                                   IOException

Deprecated. Resulting logrecords do not indicate status which is not good enough for complicated scenario like logfile rotation. It will kept around for a while, but will be eventually replaced by readOldestMsgRecords(int).

Retrieve the oldest n messages and return them in an array list. This method always refers to the currently available oldest messages which may be different due to the rotating feature(not covered at this stage) from the constantly growing output file size.

Specified by:

readOldestRecords in interface IReadableLog

Parameters:

numMsg - Number of messages (>0) to be retrieved

Returns:

Each retrieved messages packed in an array list.

Throws:

UnsupportedFormatException

IllegalArgumentException - Negative number or zero messages requested

IOException - Problem reading data from output file

readPrevRecords

public ArrayList readPrevRecords(int numMsg)
                          throws IllegalArgumentException,
                                 UnsupportedFormatException,
                                 IOException

Deprecated. Resulting logrecords do not indicate status which is not good enough for complicated scenario like logfile rotation. It will kept around for a while, but will be eventually replaced by readPrevMsgRecords(int).

Continue retrieving x relatively older messages, picked from the point where the last message read from the previous read operation, with respective to the direction of the previous read operation.

If this method is called without a prior call to readLatestRecords(int) or readOldestRecords(int), this will behave the same as calling readLatestRecords(numMsg) .
Messages are returned in an array list.

Specified by:

readPrevRecords in interface IReadableLog

Parameters:

numMsg - Number of messages(>0) to be retrieved

Returns:

Each retrieved messages packed in an array list.

Throws:

UnsupportedFormatException

IllegalArgumentException - Negative number or zero messages requested

IOException - Problem reading data from output file

readNextRecords

public ArrayList readNextRecords(int numMsg)
                          throws IllegalArgumentException,
                                 UnsupportedFormatException,
                                 IOException

Deprecated. Resulting logrecords do not indicate status which is not good enough for complicated scenario like logfile rotation. It will kept around for a while, but will be eventually replaced by readNextMsgRecords(int).

Continue retrieving x relatively newer messages, picked from the point where the last message read from the previous read operation, with respective to the direction of the previous read operation.

If this method is called without a prior call to readLatestRecords(int) or readOldestRecords(int), this will behave the same as calling readOldestRecords(numMsg) .
Messages are returned in an array list.

Specified by:

readNextRecords in interface IReadableLog

Parameters:

numMsg - Number of messages(>0) to be retrieved

Returns:

Each retrieved messages packed in an array list.

Throws:

UnsupportedFormatException

IllegalArgumentException - Negative number or zero messages requested

IOException - Problem reading data from output file

length

public long length()

Deprecated. Use getFileLenght()