org.drombler.commons.context

Class ProxyContext

java.lang.Object

org.drombler.commons.context.AbstractContext

org.drombler.commons.context.ProxyContext

All Implemented Interfaces:

Context

public class ProxyContext
extends AbstractContext

A Context which proxies other contexts.

Author:

puce

Constructor Summary

Constructors

Constructor and Description
ProxyContext()

Method Summary

Modifier and Type	Method and Description
void	addContext(Context context) Adds another Context to be proxied by this context.
<T> void	addContextListener(Class<T> type, ContextListener<T> listener) Registers a ContextListener for a specified type.
void	addContexts(List<Context> contexts)
<T> T	find(Class<T> type) Finds an instance of the specified type in this context.
<T> Collection<? extends T>	findAll(Class<T> type) Finds all instances of the specified type in this context.
boolean	isEmpty() Indicates if this proxy has some contexts.
void	removeContext(Context context) Removes a Context from being proxied by this context
<T> void	removeContextListener(Class<T> type, ContextListener<T> listener) Unregisters a ContextListener for a specified type.
void	setContexts(Context... contexts) Sets the contexts to be proxied by this context.
void	setContexts(List<? extends Context> contexts) Sets the contexts to be proxied by this context.

Methods inherited from class org.drombler.commons.context.AbstractContext

fireContextEvent, getListeners

Methods inherited from class java.lang.Object

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

Constructor Detail

ProxyContext

public ProxyContext()

Method Detail

find

public <T> T find(Class<T> type)

Finds an instance of the specified type in this context. If this context has more than one instance of the specified type, the first one found will be returned.

Type Parameters:

T - the specified type

Parameters:

type - the specified type

Returns:

the first instance found in this context with the specified type, or null if no instance was found. TODO: return Optional?

findAll

public <T> Collection<? extends T> findAll(Class<T> type)

Finds all instances of the specified type in this context.

Type Parameters:

T - the specified type

Parameters:

type - the specified type

Returns:

a collection with all instances found in this context with the specified type, or an empty collection if no instance was found TODO: return List instead of Collection?
TODO: return <T> instead of <? extends T>?

addContextListener

public <T> void addContextListener(Class<T> type,
                                   ContextListener<T> listener)

Registers a ContextListener for a specified type. The listener will be notified when instances of the specified type get added or removed.

Specified by:

addContextListener in interface Context

Overrides:

addContextListener in class AbstractContext

Type Parameters:

T - the specified type

Parameters:

type - the type to listen for

listener - the ContextListener

removeContextListener

public <T> void removeContextListener(Class<T> type,
                                      ContextListener<T> listener)

Unregisters a ContextListener for a specified type.

Specified by:

removeContextListener in interface Context

Overrides:

removeContextListener in class AbstractContext

Type Parameters:

T - the specified type

Parameters:

type - the type to listen for

listener - the ContextListener

addContext

public void addContext(Context context)

Adds another Context to be proxied by this context.

Parameters:

context - a Context to be proxied

addContexts

public void addContexts(List<Context> contexts)

removeContext

public void removeContext(Context context)

Removes a Context from being proxied by this context

Parameters:

context - the context to removed

setContexts

public void setContexts(Context... contexts)

Sets the contexts to be proxied by this context. This will remove all contexts registered before.

Parameters:

contexts - the contexts to be proxied

setContexts

public void setContexts(List<? extends Context> contexts)

Sets the contexts to be proxied by this context. This will remove all contexts registered before.

Parameters:

contexts - the contexts to be proxied

isEmpty

public boolean isEmpty()

Indicates if this proxy has some contexts.

Returns:

true, if the proxy has no contexts, else false