org.torweg.pulse.vfs
Class VirtualFileSystem

java.lang.Object
  org.torweg.pulse.vfs.VirtualFileSystem

public final class VirtualFileSystem
extends java.lang.Object

the VirtualFileSystem is a singleton providing access to VirtualFiles.

The VirtualFileSystem actually uses VFSProviders to access the individual VirtualFiles. The VirtualFileSystem consists of two stores: a private and a public store. VirtualFiles stored in the public store will also be available via HTTP. Moreover, each store may have a different VFSProvider.

A VirtualFile is identified via its URI. URIs for VirtualFiles must contain a scheme and a path. The scheme may either be public for public files, or private for private files. The URIs must not contain authority, host or port information as well as fragments or queries.

Example for a URI identifying a private file file.txt in a top level directory directory:
private:///directory/file.txt

Example for a URI identifying a public file something.txt in the root directory:
public:///something.txt

Version:

$Revision: 2071 $

Author:

Thomas Weber

Method Summary

boolean	delete(VirtualFile file) deletes the given VirtualFile and purges it from the VirtualFileSystems full text search index.
protected boolean	distribute(VirtualFile file, User user) distributes the VirtualFile.
boolean	exists(java.net.URI uri) returns whether the URI identifies an existing object.
VirtualFile	fromHttpURI(java.net.URI uri) checks if the given HTTP URI denotes a VirtualFile.
java.util.Collection<DeadProperty>	getAllDeadProperties() returns prototypes of all known dead properties.
java.util.Collection<DeadProperty>	getAllDeadProperties(org.hibernate.Session s) returns prototypes of all known dead properties using the given session.
long	getCreated(java.net.URI uri, User user) returns the creation date of the VirtualFile identified by the given URI.
long	getFileSize(java.net.URI uri, User user) returns the size of the VirtualFile identified by the given URI.
java.net.URI	getHttpURI(VirtualFile file) resolves the HTTP path to the given VirtualFile.
VFInputStream	getInputStream(VirtualFile file) provides an InputStream to read the VirtualFile .
static VirtualFileSystem	getInstance() provides access to the VirtualFileSystem.
long	getLastModified(java.net.URI uri, User user) returns the last modification date of the VirtualFile identified by the given URI.
VFOutputStream	getOutputStream(VirtualFile file, User user) provides an OutputStream to write the VirtualFile.
java.lang.String	getPrivateHTTPBase() return the private HTTP base URI.
protected VFSProvider	getPrivateProvider() returns the private provider.
protected VFSProvider	getProvider(java.net.URI uri) returns the VFSProvider for the given URI.
VFSProvider	getProvider(VirtualFile f) returns the VFSProvider for the given VirtualFile.
java.lang.String	getPublicHTTPBase() return the public HTTP base URI.
protected VFSProvider	getPublicProvider() returns the public provider.
VirtualFile	getVirtualFile(java.lang.String path, User user) returns a VirtualFile for the given path.
VirtualFile	getVirtualFile(java.net.URI uri, User user) returns a VirtualFile for the given path.
protected void	index(VirtualFile file) indexes the given VirtualFile for full text search.
static VirtualFileSystem	init(org.jdom.Element conf) initialises and configures the VirtualFileSystem.
boolean	isCollection(java.net.URI uri) returns whether the URI identifies a collection.
boolean	isResource(java.net.URI uri) returns whether the URI identifies a resource.
protected VirtualFile	loadVirtualFile(java.net.URI path) tries to load a VirtualFile for the given path.
VirtualFile	loadVirtualFile(java.net.URI path, org.hibernate.Session s) tries to load a VirtualFile for the given path.
protected void	markModified(VirtualFile file, User user) updates the modification tokens for the file.
boolean	mkdir(VirtualFile dir, User user) creates a new directory.
protected void	setPrivateProvider(VFSProvider p)
protected void	setPublicProvider(VFSProvider p)
void	updateFileSize(VirtualFile file) updates the file size for the given file but does not save the changes in the database.

Methods inherited from class java.lang.Object

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

Method Detail

loadVirtualFile

protected VirtualFile loadVirtualFile(java.net.URI path)
                               throws java.io.IOException

tries to load a VirtualFile for the given path.

Utility method for an atomic load.

Parameters:

path - the path

Returns:

the VirtualFile or null, if no such file exists.

Throws:

java.io.IOException - on errors loading the file

loadVirtualFile

public VirtualFile loadVirtualFile(java.net.URI path,
                                   org.hibernate.Session s)
                            throws java.io.IOException

tries to load a VirtualFile for the given path.

Parameters:

path - the path

s - the session with current transaction

Returns:

the VirtualFile or null, if no such file exists.

Throws:

java.io.IOException - on errors loading the file

getPrivateProvider

protected VFSProvider getPrivateProvider()

returns the private provider.

Returns:

the private provider

setPrivateProvider

protected void setPrivateProvider(VFSProvider p)

Parameters:

p - the private provider to set

getPublicProvider

protected VFSProvider getPublicProvider()

returns the public provider.

Returns:

the public provider

setPublicProvider

protected void setPublicProvider(VFSProvider p)

Parameters:

p - the public provider to set

getProvider

protected VFSProvider getProvider(java.net.URI uri)

returns the VFSProvider for the given URI.

Parameters:

uri - the URI

Returns:

the provider or null, if no such provider exists

getProvider

public VFSProvider getProvider(VirtualFile f)

returns the VFSProvider for the given VirtualFile.

Parameters:

f - the file

Returns:

the provider

markModified

protected void markModified(VirtualFile file, User user)

updates the modification tokens for the file.

Parameters:

file - the file

user - the user

distribute

protected boolean distribute(VirtualFile file, User user)

distributes the VirtualFile.

Parameters:

file - the VirtualFile to be distributed

user - the user who modified the file

Returns:

true if the distribution has been successful; otherwise false

index

protected void index(VirtualFile file)

indexes the given VirtualFile for full text search.

This method is called upon VFOutputStream.close() to start the indexing.

TODO: has to be implemented yet

Parameters:

file - the file to be indexed

getInputStream

public VFInputStream getInputStream(VirtualFile file)
                             throws VFIOException

provides an InputStream to read the VirtualFile .

Parameters:

file - the VirtualFile to be read from the InputStream

Returns:

an InputStream to read from the VirtualFile

Throws:

VFIOException - on errors aquiring the InputStream

getOutputStream

public VFOutputStream getOutputStream(VirtualFile file, User user)
                               throws VFIOException

provides an OutputStream to write the VirtualFile.

Parameters:

file - the VirtualFile to be written to by the OutputStream

user - the user used to access the file

Returns:

an OutputStream to read from the VirtualFile

Throws:

VFIOException - on errors aquiring the OutputStream

updateFileSize

public void updateFileSize(VirtualFile file)

updates the file size for the given file but does not save the changes in the database.

Parameters:

file - the file

delete

public boolean delete(VirtualFile file)

deletes the given VirtualFile and purges it from the VirtualFileSystems full text search index.

Parameters:

file - the VirtualFile to be deleted

Returns:

true, if successful. Otherwise false.

getInstance

public static VirtualFileSystem getInstance()

provides access to the VirtualFileSystem.

Returns:

the VirtualFileSystem singleton

getVirtualFile

public VirtualFile getVirtualFile(java.lang.String path, User user)
                           throws java.io.IOException,
                                  java.net.URISyntaxException

returns a VirtualFile for the given path.

Parameters:

path - the path locating the VirtualFile

user - the User to be used for access checks

Returns:

a VirtualFile for the given path.

Throws:

java.io.IOException - on errors accessing the VirtualFile

java.net.URISyntaxException - on errors parsing the URI

getVirtualFile

public VirtualFile getVirtualFile(java.net.URI uri, User user)
                           throws java.io.IOException

returns a VirtualFile for the given path.

Parameters:

uri - the path locating the VirtualFile

user - the User to be used for access checks

Returns:

a VirtualFile for the given path.

Throws:

java.io.IOException - on errors accessing the VirtualFile

getAllDeadProperties

public java.util.Collection<DeadProperty> getAllDeadProperties()

returns prototypes of all known dead properties.

Returns:

prototypes of all known dead properties

getAllDeadProperties

public java.util.Collection<DeadProperty> getAllDeadProperties(org.hibernate.Session s)

returns prototypes of all known dead properties using the given session.

It is assumed that the transaction is controlled by the caller.

Parameters:

s - the Hibernate^TM session

Returns:

prototypes of all known dead properties

getHttpURI

public java.net.URI getHttpURI(VirtualFile file)

resolves the HTTP path to the given VirtualFile.

Parameters:

file - the VirtualFile to be resolved

Returns:

the URI to the VirtualFile or null, if the VirtualFile is private

fromHttpURI

public VirtualFile fromHttpURI(java.net.URI uri)

checks if the given HTTP URI denotes a VirtualFile.

Parameters:

uri - the HTTP uri

Returns:

the VirtualFile or null, if the URI does not denote a VirtualFile

getFileSize

public long getFileSize(java.net.URI uri, User user)
                 throws java.io.IOException

returns the size of the VirtualFile identified by the given URI.

Parameters:

uri - the uri

user - the user

Returns:

the size

Throws:

java.io.IOException - on errors

getCreated

public long getCreated(java.net.URI uri, User user)
                throws java.io.IOException

returns the creation date of the VirtualFile identified by the given URI.

Parameters:

uri - the uri

user - the user

Returns:

the creation date

Throws:

java.io.IOException - on errors

getLastModified

public long getLastModified(java.net.URI uri, User user)
                     throws java.io.IOException

returns the last modification date of the VirtualFile identified by the given URI.

Parameters:

uri - the uri

user - the user

Returns:

the last modification date

Throws:

java.io.IOException - on errors

isCollection

public boolean isCollection(java.net.URI uri)
                     throws java.io.IOException

returns whether the URI identifies a collection.

Parameters:

uri - the URI

Returns:

true, if and only if the URI identifies a collection. Otherwise false.

Throws:

java.io.IOException - on errors

isResource

public boolean isResource(java.net.URI uri)
                   throws java.io.IOException

returns whether the URI identifies a resource.

Parameters:

uri - the URI

Returns:

true, if and only if the URI identifies a resource. Otherwise false.

Throws:

java.io.IOException - on errors

exists

public boolean exists(java.net.URI uri)
               throws java.io.IOException

returns whether the URI identifies an existing object.

Parameters:

uri - the URI

Returns:

true, if and only if the URI identifies an existing object. Otherwise false.

Throws:

java.io.IOException - on errors

mkdir

public boolean mkdir(VirtualFile dir, User user)
              throws VFIOException

creates a new directory.

Parameters:

dir - the directory to be created

user - the user who creates the directory

Returns:

true, if and only if the directory has been created

Throws:

VFIOException - on errors creating the directory

getPublicHTTPBase

public java.lang.String getPublicHTTPBase()

return the public HTTP base URI.

Returns:

the public HTTP base URI

getPrivateHTTPBase

public java.lang.String getPrivateHTTPBase()

return the private HTTP base URI.

Returns:

the private HTTP base URI

init

public static VirtualFileSystem init(org.jdom.Element conf)

initialises and configures the VirtualFileSystem.

Parameters:

conf - the configuration element

Returns:

the configured singleton