org.gcube.common.searchservice.searchlibrary.resultset.helpers

Class RSFileHelper

java.lang.Object

org.gcube.common.searchservice.searchlibrary.resultset.helpers.RSFileHelper

public class RSFileHelper
extends Object

Helper class of the ResultSet element

Author:

UoA

Constructor Summary

Constructors

Constructor and Description
RSFileHelper()

Method Summary

Methods

Modifier and Type	Method and Description
static String	contentToHeader(String contentName) Converts a content file name to the respective header one.
static void	copy(ResultSet rs, String src, DataOutputStream dst) Copies the source file to a new file
static void	copy(String src, DataOutputStream dst) Copies the source file to an output stream
static void	copy(String src, String dst) Copies the source file to a new file
static boolean	forceConsistency(String filename) forces the filesystem to remain consistent by using metadata changing functions
static String	generateName(short type, String seed) Generates a name of the type that is provided which can either be unique or have the unique value part equal to the provided one
static DataInputStream	getBinaryContent(String file, Mnemonic mne) Retrieves the full content of the provided file
static byte[]	getBytesFromFile(File file) Read file into a byte array
static String	getContent(String file, Mnemonic mne) Retrieves the full content of the provided file
static int	getNumberOfResultsInTextFile(String filename) Retrives the number of results in the provided file that has been structured as a text payload part
static String	headerToContent(String headerName) Converts a header file name to the respective content one.
static String	headToFlowControl(String head) Constructs the flag used for on demand production file that corresponds to the specfic head part
static String	headToFlowControlTmp(String head) Constructs the temporary flag used for on demand production file that corresponds to the specfic head part
static boolean	isReady(String filename) Checks if the provided file is ready for consumption
static void	notifyOnFlowCreation(String headname) notidies the consumer that more records were created
static void	persistContent(String filename, String inWrap, Mnemonic mne) Persists the content of the provided source file to the provided target file
static void	persistContent(String filename, Vector<String> results, int count, Mnemonic mne) Persists the content available in the provided vector o a file whose name is given.
static void	persistHeader(HeaderRef header) Persists a header file with the information available in its argument
static String	persistStream(InputStream content) persists the stream in a file and returns the filename
static HeaderRef	populateHeader(String filename) Populates a header info class instance from the content of the provided file
static Vector<String>	populateResults(String filename, Mnemonic mne) Populates a record vecror with the records available in the provided file
static String	publicToTmp(String pubName) Converts a public file name to a private temparary one
static void	requestFlowCreation(String headname) notifies the producer of an RS that more records are needed
static void	runGC() Attempt to call the garbage collector
static String[]	splitFile(String filename) Splits the provided file in smaller parts as is dictated by RSConstants.partSize
static String	tmpToPublic(String tmpName) Converts a tmp file name to a public one
static void	touchHeader(String filename) Populates a header info class instance from the content of the provided file
static boolean	waitForIt(String filename, boolean flowControl, String headname) Waits until the provided file is ready to be consumed or a maximum amount of time has been reached.
static boolean	waitForIt(String filename, long time, boolean flowControl, String headname) Waits until the provided file is ready to be consumed or a maximum amount of time has been reached.
static RSConstants.CONTROLFLOW	waitOnFlowNotification(String headname, long time) blocks waiting for notifications on result production for the specified time period

Methods inherited from class java.lang.Object

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

Constructor Detail

RSFileHelper

public RSFileHelper()

Method Detail

generateName

public static String generateName(short type,
                  String seed)
                           throws Exception

Generates a name of the type that is provided which can either be unique or have the unique value part equal to the provided one

Parameters:

type - The type of filename to generate. This can be one of RSConstants.CONTENT, RSConstants.HEADER, RSConstants.PAGEDCONTENT

seed - If a non null value is provided, The unique part of the generated file will have the supplied value. Otherwise, a unique value is generated and used

Returns:

The generated file name

Throws:

Exception - An unrecoverable for the operation error occured

headToFlowControl

public static String headToFlowControl(String head)

Constructs the flag used for on demand production file that corresponds to the specfic head part

Parameters:

head - The head file of the RS

Returns:

the flag file

headToFlowControlTmp

public static String headToFlowControlTmp(String head)

Constructs the temporary flag used for on demand production file that corresponds to the specfic head part

Parameters:

head - The head file of the RS

Returns:

the flag file

waitOnFlowNotification

public static RSConstants.CONTROLFLOW waitOnFlowNotification(String headname,
                                             long time)

blocks waiting for notifications on result production for the specified time period

Parameters:

headname - The head file

time - The timeout

Returns:

The status of the request

notifyOnFlowCreation

public static void notifyOnFlowCreation(String headname)

notidies the consumer that more records were created

Parameters:

headname - The head name of the RS that needed more results

requestFlowCreation

public static void requestFlowCreation(String headname)

notifies the producer of an RS that more records are needed

Parameters:

headname - The head name of the RS that needs more results

publicToTmp

public static String publicToTmp(String pubName)
                          throws Exception

Converts a public file name to a private temparary one

Parameters:

pubName - The file name to convert

Returns:

The temporary name

Throws:

Exception - An unrecoverable for the operation error occured

tmpToPublic

public static String tmpToPublic(String tmpName)
                          throws Exception

Converts a tmp file name to a public one

Parameters:

tmpName - the temporary name

Returns:

the public name

Throws:

Exception - An unrecoverable for the operation error occured

headerToContent

public static String headerToContent(String headerName)
                              throws Exception

Converts a header file name to the respective content one.

Parameters:

headerName - THe header name to convert

Returns:

The respective content one

Throws:

Exception - An unrecoverable for the operation error occured

contentToHeader

public static String contentToHeader(String contentName)
                              throws Exception

Converts a content file name to the respective header one.

Parameters:

contentName - The content name to convert

Returns:

The respective header one

Throws:

Exception - An unrecoverable for the operation error occured

persistContent

public static void persistContent(String filename,
                  Vector<String> results,
                  int count,
                  Mnemonic mne)
                           throws Exception

Persists the content available in the provided vector o a file whose name is given. The number of content records to persist is given as a parameter

Parameters:

filename - The filename to perist the content in

results - The vector holding the payload

mne - the encryption class

count - The number of records to persist. If this is negative, all the available records are persisted

Throws:

Exception - An unrecoverable for the operation error occured

forceConsistency

public static boolean forceConsistency(String filename)
                                throws Exception

forces the filesystem to remain consistent by using metadata changing functions

Parameters:

filename - the filename

Returns:

whether or not the forcing was successful

Throws:

Exception - An error has occured

persistContent

public static void persistContent(String filename,
                  String inWrap,
                  Mnemonic mne)
                           throws Exception

Persists the content of the provided source file to the provided target file

Parameters:

filename - The target file

inWrap - The source file

mne - the encryption class

Throws:

Exception - An unrecoverable for the operation error occurred

persistHeader

public static void persistHeader(HeaderRef header)
                          throws Exception

Persists a header file with the information available in its argument

Parameters:

header - The header info

Throws:

Exception - An unrecoverable for the operation error occured

populateHeader

public static HeaderRef populateHeader(String filename)
                                throws Exception

Populates a header info class instance from the content of the provided file

Parameters:

filename - The file holding the header payload

Returns:

The Header info

Throws:

Exception - An unrecoverable for the operation error occured

touchHeader

public static void touchHeader(String filename)

Populates a header info class instance from the content of the provided file

Parameters:

filename - The file holding the header to touch

waitForIt

public static boolean waitForIt(String filename,
                boolean flowControl,
                String headname)

Waits until the provided file is ready to be consumed or a maximum amount of time has been reached. The maximum amount of time is the one declared in RSConstants.sleepMax in milliseconds

Parameters:

filename - The filename to wait for

flowControl - whether or not the RS supports on demand production of results

headname - The head file name of this RS

Returns:

whether or not the filename if ready to be read

waitForIt

public static boolean waitForIt(String filename,
                long time,
                boolean flowControl,
                String headname)

Waits until the provided file is ready to be consumed or a maximum amount of time has been reached. The maximum amount of time is the one provided in milliseconds

Parameters:

filename - The filename to wait for

time - The maximum time in milliseconds to wait for the file

flowControl - whether or not the RS supports on demand production of results

headname - The head file name of this RS

Returns:

whether or not the filename if ready to be read

isReady

public static boolean isReady(String filename)

Checks if the provided file is ready for consumption

Parameters:

filename - The name of the file to check if it is ready

Returns:

true if it is, false otherwise

populateResults

public static Vector<String> populateResults(String filename,
                             Mnemonic mne)
                                      throws Exception

Populates a record vecror with the records available in the provided file

Parameters:

filename - The file to retrieve the records from

mne - the encryption class

Returns:

The populated vector

Throws:

Exception - An unrecoverable for the operation error occured

getContent

public static String getContent(String file,
                Mnemonic mne)
                         throws Exception

Retrieves the full content of the provided file

Parameters:

file - The file whose content must be retrieved

mne - the encryption class

Returns:

The full file content

Throws:

Exception - An unrecoverable for the operation error occurred

getBinaryContent

public static DataInputStream getBinaryContent(String file,
                               Mnemonic mne)
                                        throws Exception

Retrieves the full content of the provided file

Parameters:

file - The file whose content must be retrieved

mne - the encryption class

Returns:

The full file content

Throws:

Exception - An unrecoverable for the operation error occurred

splitFile

public static String[] splitFile(String filename)
                          throws Exception

Splits the provided file in smaller parts as is dictated by RSConstants.partSize

Parameters:

filename - The file to split

Returns:

A vector holding the names of the created parts

Throws:

Exception - An unrecoverable for the operation error occured

copy

public static void copy(String src,
        DataOutputStream dst)
                 throws Exception

Copies the source file to an output stream

Parameters:

src - The source file

dst - The destination stream

Throws:

Exception - An unrecoverable for the operation error occured

copy

public static void copy(String src,
        String dst)
                 throws Exception

Copies the source file to a new file

Parameters:

src - The source file

dst - The destination file

Throws:

Exception - An unrecoverable for the operation error occured

copy

public static void copy(ResultSet rs,
        String src,
        DataOutputStream dst)
                 throws Exception

Copies the source file to a new file

Parameters:

rs - the RS

src - The source file

dst - The destination file

Throws:

Exception - An unrecoverable for the operation error occurred

persistStream

public static String persistStream(InputStream content)
                            throws Exception

persists the stream in a file and returns the filename

Parameters:

content - the stream to persist

Returns:

the filename

Throws:

Exception - an unrecoverable for the operation error occurred

getNumberOfResultsInTextFile

public static int getNumberOfResultsInTextFile(String filename)
                                        throws Exception

Retrives the number of results in the provided file that has been structured as a text payload part

Parameters:

filename - The file to retrieve the records from

Returns:

The number of records

Throws:

Exception - An unrecoverable for the operation error occured

getBytesFromFile

public static byte[] getBytesFromFile(File file)
                               throws Exception

Read file into a byte array

Parameters:

file - The File handler

Returns:

A byte array that stores the file content

Throws:

Exception - in case of error

runGC

public static void runGC()

Attempt to call the garbage collector