Package org.apache.jackrabbit.vfs.ext.ds

Class VFSBackend

java.lang.Object

org.apache.jackrabbit.core.data.AbstractBackend

org.apache.jackrabbit.vfs.ext.ds.VFSBackend

All Implemented Interfaces:

Backend

public class VFSBackend
extends AbstractBackend

A data store backend that stores data on VFS file system.

Constructor Summary

Constructors

Constructor	Description
VFSBackend(org.apache.commons.vfs2.FileObject baseFolder)

Method Summary

Modifier and Type	Method	Description
Set<DataIdentifier>	deleteAllOlderThan(long timestamp)	Delete all records which are older than timestamp.
void	deleteRecord(DataIdentifier identifier)	Delete record identified by identifier.
boolean	exists(DataIdentifier identifier)	This method check the existence of record in backend.
boolean	exists(DataIdentifier identifier, boolean touch)	This method check the existence of record in backend.
Iterator<DataIdentifier>	getAllIdentifiers()	Returns identifiers of all records that exists in backend.
protected int	getAsyncWriteExecutorActiveCount()	Returns the approximate number of threads that are actively executing asynchronous writing tasks.
protected org.apache.commons.vfs2.FileObject	getBaseFolderObject()	Returns the VFS base folder object.
protected org.apache.commons.vfs2.FileObject	getExistingFileObject(DataIdentifier identifier)	Returns the identified file object.
long	getLastModified(DataIdentifier identifier)	Return lastModified of record identified by identifier.
long	getLength(DataIdentifier identifier)	Return length of record identified by identifier.
protected org.apache.commons.vfs2.FileObject	getTouchFileObject(org.apache.commons.vfs2.FileObject fileObject, boolean create)	Returns the touch file for the fileObject.
void	init(CachingDataStore store, String homeDir, String config)	This method initialize backend with the configuration.
protected boolean	isTouchFileObject(org.apache.commons.vfs2.FileObject fileObject)	Returns true if the fileObject is used for touching purpose.
boolean	isTouchFilePreferred()	Returns true if a touch file should be used to save/get the last modified time for a file object.
InputStream	read(DataIdentifier identifier)	Return inputstream of record identified by identifier.
protected org.apache.commons.vfs2.FileObject	resolveFileObject(DataIdentifier identifier)	Returns a resolved identified file object.
protected String	resolveFileObjectRelPath(DataIdentifier identifier)	Returns a resolved relative file object path by the given entry identifier.
void	setTouchFilePreferred(boolean touchFilePreferred)	Sets whether or not a touch file should be used to save/get the last modified timestamp for a file object.
void	touch(DataIdentifier identifier, long minModifiedDate)	Update the lastModified of record if it's lastModified < minModifiedDate.
void	touchAsync(DataIdentifier identifier, long minModifiedDate, AsyncTouchCallback callback)	Update the lastModified of record if it's lastModified < minModifiedDate asynchronously.
void	write(DataIdentifier identifier, File file)	Stores file to backend with identifier used as key.
void	writeAsync(DataIdentifier identifier, File file, AsyncUploadCallback callback)	Write file to backend in asynchronous mode.

Methods inherited from class org.apache.jackrabbit.core.data.AbstractBackend

close, createAsyncWriteExecutor, getAsyncWriteExecutor, getAsyncWritePoolSize, getConfig, getDataStore, getHomeDir, setAsyncWritePoolSize, setConfig, setDataStore, setHomeDir

Methods inherited from class java.lang.Object

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

Constructor Detail

VFSBackend

public VFSBackend(org.apache.commons.vfs2.FileObject baseFolder)

Method Detail

init

public void init(CachingDataStore store,
                 String homeDir,
                 String config)
          throws DataStoreException

This method initialize backend with the configuration.

Specified by:

init in interface Backend

Overrides:

init in class AbstractBackend

Parameters:

store - CachingDataStore

homeDir - path of repository home dir.

config - path of config property file.

Throws:

DataStoreException

read

public InputStream read(DataIdentifier identifier)
                 throws DataStoreException

Return inputstream of record identified by identifier.

Parameters:

identifier - identifier of record.

Returns:

inputstream of the record.

Throws:

DataStoreException - if record not found or any error.

getLength

public long getLength(DataIdentifier identifier)
               throws DataStoreException

Return length of record identified by identifier.

Parameters:

identifier - identifier of record.

Returns:

length of the record.

Throws:

DataStoreException - if record not found or any error.

getLastModified

public long getLastModified(DataIdentifier identifier)
                     throws DataStoreException

Return lastModified of record identified by identifier.

Parameters:

identifier - identifier of record.

Returns:

lastModified of the record.

Throws:

DataStoreException - if record not found or any error.

write

public void write(DataIdentifier identifier,
                  File file)
           throws DataStoreException

Stores file to backend with identifier used as key. If key pre-exists, it updates the timestamp of the key.

Parameters:

identifier - key of the file

file - file that would be stored in backend.

Throws:

DataStoreException - for any error.

writeAsync

public void writeAsync(DataIdentifier identifier,
                       File file,
                       AsyncUploadCallback callback)
                throws DataStoreException

Write file to backend in asynchronous mode.

callback - Callback interface to called after upload succeed or failed.

Throws:

DataStoreException

getAllIdentifiers

public Iterator<DataIdentifier> getAllIdentifiers()
                                           throws DataStoreException

Returns identifiers of all records that exists in backend.

Returns:

iterator consisting of all identifiers

Throws:

DataStoreException

exists

public boolean exists(DataIdentifier identifier,
                      boolean touch)
               throws DataStoreException

This method check the existence of record in backend. Return true if records exists else false. This method also touch record identified by identifier if touch is true.

Throws:

DataStoreException

exists

public boolean exists(DataIdentifier identifier)
               throws DataStoreException

This method check the existence of record in backend.

Parameters:

identifier - identifier to be checked.

Returns:

true if records exists else false.

Throws:

DataStoreException

touch

public void touch(DataIdentifier identifier,
                  long minModifiedDate)
           throws DataStoreException

Update the lastModified of record if it's lastModified < minModifiedDate.

Throws:

DataStoreException

touchAsync

public void touchAsync(DataIdentifier identifier,
                       long minModifiedDate,
                       AsyncTouchCallback callback)
                throws DataStoreException

Update the lastModified of record if it's lastModified < minModifiedDate asynchronously. Result of update is passed using appropriate AsyncTouchCallback methods. If identifier's lastModified > minModified AsyncTouchCallback.onAbort(AsyncTouchResult) is called. Any exception is communicated through AsyncTouchCallback.onFailure(AsyncTouchResult) . On successful update of lastModified, AsyncTouchCallback.onSuccess(AsyncTouchResult) is invoked.

Throws:

DataStoreException

deleteAllOlderThan

public Set<DataIdentifier> deleteAllOlderThan(long timestamp)
                                       throws DataStoreException

Delete all records which are older than timestamp.

Returns:

Set of identifiers which are deleted.

Throws:

DataStoreException

deleteRecord

public void deleteRecord(DataIdentifier identifier)
                  throws DataStoreException

Delete record identified by identifier. No-op if identifier not found.

Throws:

DataStoreException

isTouchFilePreferred

public boolean isTouchFilePreferred()

Returns true if a touch file should be used to save/get the last modified time for a file object. True by default unless the getBaseFolderObject() is representing a local file system folder (e.g, file://...).

When returns true, this backend creates a separate file named by the original file base name followed by this touch file name suffix. So, this backend can set the last modified time on the separate touch file instead of trying to do it on the original entry file. For example, WebDAV file system doesn't allow to modify the last modified time on a file.

Returns:

true if a touch file should be used to save/get the last modified time for a file object

setTouchFilePreferred

public void setTouchFilePreferred(boolean touchFilePreferred)

Sets whether or not a touch file should be used to save/get the last modified timestamp for a file object.

Parameters:

touchFilePreferred - whether or not a touch file should be used to save/get the last modified timestamp for a file object

getBaseFolderObject

protected org.apache.commons.vfs2.FileObject getBaseFolderObject()

Returns the VFS base folder object.

Returns:

the VFS base folder object

resolveFileObject

protected org.apache.commons.vfs2.FileObject resolveFileObject(DataIdentifier identifier)
                                                        throws DataStoreException

Returns a resolved identified file object. This method implements the pattern used to avoid problems with too many files in a single folder.

Parameters:

identifier - data identifier

Returns:

identified file object

Throws:

DataStoreException - if any file system exception occurs

resolveFileObjectRelPath

protected String resolveFileObjectRelPath(DataIdentifier identifier)

Returns a resolved relative file object path by the given entry identifier.

Parameters:

identifier - entry identifier

Returns:

a resolved relative file object path by the given entry identifier

getExistingFileObject

protected org.apache.commons.vfs2.FileObject getExistingFileObject(DataIdentifier identifier)
                                                            throws DataStoreException

Returns the identified file object. If not existing, returns null.

Parameters:

identifier - data identifier

Returns:

identified file object

Throws:

DataStoreException - if any file system exception occurs

isTouchFileObject

protected boolean isTouchFileObject(org.apache.commons.vfs2.FileObject fileObject)

Returns true if the fileObject is used for touching purpose.

Parameters:

fileObject - file object

Returns:

true if the fileObject is used for touching purpose

getTouchFileObject

protected org.apache.commons.vfs2.FileObject getTouchFileObject(org.apache.commons.vfs2.FileObject fileObject,
                                                                boolean create)
                                                         throws DataStoreException

Returns the touch file for the fileObject. If there's no corresponding touch file existing, then returns null when create is false. When create is true, it creates a new touch file if no corresponding touch file exists.

Parameters:

fileObject - file object

create - create a touch file if not existing

Returns:

touch file object

Throws:

DataStoreException - if any file system exception occurs

getAsyncWriteExecutorActiveCount

protected int getAsyncWriteExecutorActiveCount()

Returns the approximate number of threads that are actively executing asynchronous writing tasks.

Returns:

the approximate number of threads that are actively executing asynchronous writing tasks