Package db.buffers

Class ManagedBufferFileAdapter

java.lang.Object

db.buffers.BufferFileAdapter

db.buffers.ManagedBufferFileAdapter

All Implemented Interfaces:

BufferFile, ManagedBufferFile

public class ManagedBufferFileAdapter
extends BufferFileAdapter
implements ManagedBufferFile

ManagedBufferFileAdapter provides a ManagedBufferFile implementation which wraps a ManagedBufferFileHandle.

Constructor Summary

Constructors

Constructor	Description
ManagedBufferFileAdapter(ManagedBufferFileHandle remoteManagedBufferFile)	Constructor.

Method Summary

Modifier and Type	Method	Description
boolean	canSave()	Returns true if a save file is provided for creating a new version of this buffer file.
long	getCheckinID()	Returns the checkin ID corresponding to this buffer file.
byte[]	getForwardModMapData(int oldVersion)	Returns a bit map corresponding to all buffers modified since oldVersion.
BufferFile	getNextChangeDataFile(boolean getFirst)	Get the next change data file which corresponds to this buffer file.
BufferFile	getSaveChangeDataFile()	Returns a temporary change data buffer file which should be used to store a application-level ChangeSet associated with this new buffer file version.
ManagedBufferFile	getSaveFile()	Returns a Save file if available.
void	saveCompleted(boolean commit)	After getting the save file, this method must be invoked to terminate the save.
void	setVersionComment(java.lang.String comment)	Set the comment which will be associated with this buffer file if saved.

Methods inherited from class db.buffers.BufferFileAdapter

clearParameters, close, delete, dispose, get, getBufferSize, getFreeIndexes, getIndexCount, getParameter, getParameterNames, isReadOnly, isRemote, put, setFreeIndexes, setParameter, setReadOnly

Methods inherited from class java.lang.Object

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

Methods inherited from interface db.buffers.BufferFile

clearParameters, close, delete, dispose, get, getBufferSize, getFreeIndexes, getIndexCount, getParameter, getParameterNames, isReadOnly, put, setFreeIndexes, setParameter, setReadOnly

Constructor Detail

ManagedBufferFileAdapter

public ManagedBufferFileAdapter(ManagedBufferFileHandle remoteManagedBufferFile)

Constructor.

Parameters:

remoteBufferFile - remote buffer file handle

Method Detail

getSaveFile

public ManagedBufferFile getSaveFile()
                              throws java.io.IOException

Description copied from interface: ManagedBufferFile

Returns a Save file if available. Returns null if a save can not be performed. This method may block for an extended period of time if the pre-save process has not already completed. This method does not accept a monitor since a remote TaskMonitor does not yet exist.

Specified by:

getSaveFile in interface ManagedBufferFile

Throws:

java.io.IOException - if an I/O error occurs

saveCompleted

public void saveCompleted(boolean commit)
                   throws java.io.IOException

Description copied from interface: ManagedBufferFile

After getting the save file, this method must be invoked to terminate the save.

Specified by:

saveCompleted in interface ManagedBufferFile

Parameters:

commit - if true the save file will be reopened as read-only for update. If false, the save file will be deleted and the object will become invalid.

Throws:

java.io.IOException

canSave

public boolean canSave()
                throws java.io.IOException

Description copied from interface: ManagedBufferFile

Returns true if a save file is provided for creating a new version of this buffer file.

Specified by:

canSave in interface ManagedBufferFile

Throws:

java.io.IOException - if an I/O error occurs

See Also:

BufferFile.getSaveFile

setVersionComment

public void setVersionComment(java.lang.String comment)
                       throws java.io.IOException

Description copied from interface: ManagedBufferFile

Set the comment which will be associated with this buffer file if saved. The comment must be set prior to invoking close or setReadOnly.

Specified by:

setVersionComment in interface ManagedBufferFile

Parameters:

comment - comment text

Throws:

java.io.IOException - if an I/O error occurs

getNextChangeDataFile

public BufferFile getNextChangeDataFile(boolean getFirst)
                                 throws java.io.IOException

Description copied from interface: ManagedBufferFile

Get the next change data file which corresponds to this buffer file. This method acts like an iterator which each successive invocation returning the next available file. Null is returned when no more files are available. The invoker is responsible for closing each file returned. It is highly recommended that each file be closed prior to requesting the next file.

Specified by:

getNextChangeDataFile in interface ManagedBufferFile

Parameters:

getFirst - causes the iterator to reset and return the first available file.

Throws:

java.io.IOException - if an I/O error occurs

getSaveChangeDataFile

public BufferFile getSaveChangeDataFile()
                                 throws java.io.IOException

Description copied from interface: ManagedBufferFile

Returns a temporary change data buffer file which should be used to store a application-level ChangeSet associated with this new buffer file version. The getSaveFile method must be successfully invoked prior to invoking this method.

Specified by:

getSaveChangeDataFile in interface ManagedBufferFile

Returns:

change data file or null if one is not available.

Throws:

java.io.IOException - if an I/O error occurs

getCheckinID

public long getCheckinID()
                  throws java.io.IOException

Description copied from interface: ManagedBufferFile

Returns the checkin ID corresponding to this buffer file. The returned value is only valid if this buffer file has an associated buffer file manager and is either being created (see isReadOnly) or is intended for update (see canSave).

Specified by:

getCheckinID in interface ManagedBufferFile

Throws:

java.io.IOException - if an I/O error occurs

getForwardModMapData

public byte[] getForwardModMapData(int oldVersion)
                            throws java.io.IOException

Description copied from interface: ManagedBufferFile

Returns a bit map corresponding to all buffers modified since oldVersion. This identifies all buffers contained within the oldVersion which have been modified during any revision up until this file version. Buffers added since oldVersion are not identified NOTE: The bit mask may identify empty/free buffers within this file version.

Specified by:

getForwardModMapData in interface ManagedBufferFile

Parameters:

oldVersion - indicates the older version of this file for which a change map will be returned. This method may only be invoked if this file is at version 2 or higher, has an associated BufferFileManager and the oldVersion related files still exist.

Returns:

ModMap buffer change map data

Throws:

java.io.IOException - if an I/O error occurs