com.github.wuic.nut.dao.core

Class ProxyNutDao

java.lang.Object

com.github.wuic.nut.dao.core.ProxyNutDao

All Implemented Interfaces:

NutDao

public class ProxyNutDao
extends Object
implements NutDao

Internal NutDao class that maps particular path to a particular Nut or then to a particular NutDao. If the path is not mapped, then a delegated DAO is called.

Since:

0.4.4

Version:

1.0

Author:

Guillaume DROUET

Nested Class Summary

Nested classes/interfaces inherited from interface com.github.wuic.nut.dao.NutDao

NutDao.PathFormat

Constructor Summary

Constructors

Constructor and Description
ProxyNutDao(String rootPath, NutDao delegate) Builds a new instance thanks to a delegated NutDao.

Method Summary

Methods

Modifier and Type	Method and Description
void	addRule(String path, Nut nut) Adds a mapping between a path and a nut.
void	addRule(String path, NutDao dao) Adds a mapping between a path and a nut DAO.
List<Nut>	create(String path, NutDao.PathFormat format, ProcessContext processContext) Creates a list of nuts thanks to the given path.
List<Nut>	create(String path, ProcessContext processContext) Creates a list of nuts thanks to the given path considered as represented in any format.
Boolean	exists(String path, ProcessContext processContext) Indicates if the given path exists or not.
NutDao	getNutDao(String path) Gets a DAO for a particular path.
InputStream	newInputStream(String path, ProcessContext processContext) Opens the stream for the given path.
void	observe(String realPath, NutDaoListener... listeners) Adds a set of listeners to be notified when an update has been detected on the nut.
String	proxyUriFor(Nut nut) Returns an URI in a String representation of a proxy serving the given nut.
void	save(Nut nut) Saves the give nut.
Boolean	saveSupported() Indicates if this DAO is able to save a nut, which depends on the underlying protocol.
void	shutdown() Shutdowns this DAO by releasing its resources.
String	toString()
NutDao	withRootPath(String rootPath) Returns an instance that prefixes any nut name to be created with the given root path.

Methods inherited from class java.lang.Object

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

Constructor Detail

ProxyNutDao

public ProxyNutDao(String rootPath,
           NutDao delegate)

Builds a new instance thanks to a delegated NutDao.

Parameters:

rootPath - the root path that prefixes any rule

delegate - the delegated DAO

Method Detail

addRule

public void addRule(String path,
           Nut nut)

Adds a mapping between a path and a nut.

Parameters:

path - the path

nut - the nut returned when path is used

addRule

public void addRule(String path,
           NutDao dao)

Adds a mapping between a path and a nut DAO.

Parameters:

path - the path

dao - the NutDao to call when path is used

getNutDao

public NutDao getNutDao(String path)

Gets a DAO for a particular path.

Parameters:

path - the proxy path

Returns:

the mapped DAO

observe

public void observe(String realPath,
           NutDaoListener... listeners)
             throws IOException

Adds a set of listeners to be notified when an update has been detected on the nut. The targeted nut is represented by the specified path.

The listeners will be stored in a weak reference so if no strong reference to them exist, they will be garbage collected.

Specified by:

observe in interface NutDao

Parameters:

realPath - the real path name of the nut.

listeners - some listeners to be notified when an update has been detected on a nut

Throws:

IOException - if an I/O occurs while retrieving last update of the nut

create

public List<Nut> create(String path,
               ProcessContext processContext)
                 throws IOException

Creates a list of nuts thanks to the given path considered as represented in any format.

Specified by:

create in interface NutDao

Parameters:

path - the path representing the location of the nut(s)

processContext - the process context calling this method

Returns:

the created nut(s)

Throws:

IOException - if an I/O error occurs when creating the nut

See Also:

NutDao.create(String, com.github.wuic.nut.dao.NutDao.PathFormat, com.github.wuic.ProcessContext)

create

public List<Nut> create(String path,
               NutDao.PathFormat format,
               ProcessContext processContext)
                 throws IOException

Creates a list of nuts thanks to the given path.

A NutDao.PathFormat also gives information on the format used in the string representation of the given path.

Specified by:

create in interface NutDao

Parameters:

path - the path representing the location of the nut(s)

format - the path format

processContext - the process context calling this method

Returns:

the created nut(s)

Throws:

IOException - if an I/O error occurs when creating the nut

proxyUriFor

public String proxyUriFor(Nut nut)

Returns an URI in a String representation of a proxy serving the given nut.

If many proxies are defined, proxy URI is selected in a round-robin mode. Each time a proxy is used, it won't be reused until all other proxies have been used too.

Specified by:

proxyUriFor in interface NutDao

Parameters:

nut - the nut

Returns:

the proxy URI, null if not proxy is set

save

public void save(Nut nut)

Saves the give nut. An UnsupportedOperationException will be thrown if the implementation supports only nut access.

Specified by:

save in interface NutDao

Parameters:

nut - the nut to save

saveSupported

public Boolean saveSupported()

Indicates if this DAO is able to save a nut, which depends on the underlying protocol.

Specified by:

saveSupported in interface NutDao

Returns:

true if NutDao.save(Nut) is supported, false otherwise

shutdown

public void shutdown()

Shutdowns this DAO by releasing its resources.

Specified by:

shutdown in interface NutDao

withRootPath

public NutDao withRootPath(String rootPath)

Returns an instance that prefixes any nut name to be created with the given root path.

Specified by:

withRootPath in interface NutDao

Parameters:

rootPath - the root path

Returns:

the enclosed instance

newInputStream

public InputStream newInputStream(String path,
                         ProcessContext processContext)
                           throws IOException

Opens the stream for the given path.

Specified by:

newInputStream in interface NutDao

Parameters:

path - the path to access

processContext - the process context calling this method

Returns:

the stream

Throws:

IOException - if stream could not be opened

exists

public Boolean exists(String path,
             ProcessContext processContext)
               throws IOException

Indicates if the given path exists or not.

Specified by:

exists in interface NutDao

Parameters:

path - the path the DAO should be able to resolve

processContext - the process context calling this method

Returns:

true if path is resolved, false otherwise

Throws:

IOException - if any I/O error occurs

toString

public String toString()

Overrides:

toString in class Object