org.eclipse.scada.hds

Class DataFileAccessorImpl

java.lang.Object

org.eclipse.scada.hds.DataFileAccessorImpl

All Implemented Interfaces:

DataFileAccessor

public class DataFileAccessorImpl
extends Object
implements DataFileAccessor

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static interface	DataFileAccessorImpl.EntryVisitor

Field Summary

Fields

Modifier and Type	Field and Description
protected FileChannel	channel
protected Date	end
protected static int	ENTRY_SIZE
protected RandomAccessFile	file
static byte	FLAG_DELETED Entry is deleted
static byte	FLAG_ERROR Marks a value as erroneous
static byte	FLAG_HEARTBEAT Entry is a heartbeat entry
static byte	FLAG_MANUAL Marks a value as manually overridden
protected static int	HEADER_SIZE
protected Date	start

Constructor Summary

Constructors

Constructor and Description
DataFileAccessorImpl(File file)

Method Summary

Modifier and Type	Method and Description
static DataFileAccessorImpl	create(File file, Date startDate, Date endDate) Initialize a new file, write the empty structure to disk and return a new accessor to it
void	delete() Dispose and delete the file
void	dispose() Dispose the file.
void	forwardCorrect(double value, Date afterDate) Forward correct entries This deletes all entries which are after the specified date
boolean	forwardVisitAll(DataFileAccessorImpl.EntryVisitor visitor)
Date	getEnd()
Date	getStart()
void	insertValue(double value, Date date, boolean error, boolean manual, boolean heartbeat)
boolean	visit(ValueVisitor visitor)
boolean	visitFirstValue(ValueVisitor visitor)

Methods inherited from class java.lang.Object

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

Field Detail

FLAG_DELETED

public static final byte FLAG_DELETED

Entry is deleted

See Also:

Constant Field Values

FLAG_HEARTBEAT

public static final byte FLAG_HEARTBEAT

Entry is a heartbeat entry

See Also:

Constant Field Values

FLAG_MANUAL

public static final byte FLAG_MANUAL

Marks a value as manually overridden

See Also:

Constant Field Values

FLAG_ERROR

public static final byte FLAG_ERROR

Marks a value as erroneous

See Also:

Constant Field Values

HEADER_SIZE

protected static final int HEADER_SIZE

See Also:

Constant Field Values

ENTRY_SIZE

protected static final int ENTRY_SIZE

See Also:

Constant Field Values

file

protected RandomAccessFile file

channel

protected final FileChannel channel

start

protected Date start

end

protected Date end

Constructor Detail

DataFileAccessorImpl

public DataFileAccessorImpl(File file)
                     throws Exception

Throws:

Exception

Method Detail

getStart

public Date getStart()

Specified by:

getStart in interface DataFileAccessor

getEnd

public Date getEnd()

Specified by:

getEnd in interface DataFileAccessor

insertValue

public void insertValue(double value,
                        Date date,
                        boolean error,
                        boolean manual,
                        boolean heartbeat)
                 throws IOException

Specified by:

insertValue in interface DataFileAccessor

Throws:

IOException

visitFirstValue

public boolean visitFirstValue(ValueVisitor visitor)
                        throws Exception

Specified by:

visitFirstValue in interface DataFileAccessor

Throws:

Exception

forwardVisitAll

public boolean forwardVisitAll(DataFileAccessorImpl.EntryVisitor visitor)
                        throws IOException

Throws:

IOException

visit

public boolean visit(ValueVisitor visitor)
              throws IOException

Specified by:

visit in interface DataFileAccessor

Throws:

IOException

forwardCorrect

public void forwardCorrect(double value,
                           Date afterDate)
                    throws Exception

Description copied from interface: DataFileAccessor

Forward correct entries
This deletes all entries which are after the specified date

Specified by:

forwardCorrect in interface DataFileAccessor

Parameters:

value - the value

afterDate - the starting point, correct everything after

Throws:

Exception - if anything goes wrong

dispose

public void dispose()

Dispose the file. Close all resources.

Specified by:

dispose in interface DataFileAccessor

delete

public void delete()

Dispose and delete the file

Specified by:

delete in interface DataFileAccessor

create

public static DataFileAccessorImpl create(File file,
                                          Date startDate,
                                          Date endDate)
                                   throws Exception

Initialize a new file, write the empty structure to disk and return a new accessor to it

Parameters:

file - The file to create. This file must not exists.

startDate - the start date of the file

endDate - the end date of the file

Returns:

a newly created file accessor

Throws:

Exception - if anything goes wrong