de.susebox.java.lang

Class EnvironmentProvider

java.lang.Object

de.susebox.java.lang.EnvironmentProvider

public final class EnvironmentProvider
extends java.lang.Object

The EnvironmentProvider is a singleton object to store and provide Environment instances. It provides the possibility to register and retrieve Environment instances on a per object or per class base.

Since an Environment is designed as a substitute for some features of the JDK System class, the retrieval of the Environment associated with a class should be possible without additional information about the context. Class-based Environment objects are also associated with the thread, that actually registered the instance.

Author:

Heiko Blau

Constructor Summary

Constructors

Constructor and Description
EnvironmentProvider()

Method Summary

Modifier and Type	Method and Description
static Environment	getEnvironment(java.lang.Object obj) This method returns an Environment instance that has been registered for the given object.
static void	removeEnvironment(java.lang.Object obj) Removing a registered Environment.
static void	setEnvironment(java.lang.Object obj, Environment env) Registering an Environment for the given object.

Methods inherited from class java.lang.Object

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

Constructor Detail

EnvironmentProvider

public EnvironmentProvider()

Method Detail

getEnvironment

public static Environment getEnvironment(java.lang.Object obj)

This method returns an Environment instance that has been registered for the given object.
If there is no specific Environment instance available for the object then its class name is used to find a more general Environment instance.
If still no Environment could be found a default Environment is returned, usually a DefaultEnvironment instance.
The method will always return an Environment instance except for runtime exceptions.

Parameters:

obj - the object thats environment should be retrieved

Returns:

an Environment instance for the caller

See Also:

Environment, DefaultEnvironment

setEnvironment

public static void setEnvironment(java.lang.Object obj,
                                  Environment env)
                           throws java.lang.NullPointerException

Registering an Environment for the given object. If this object is a Class instance, the Environment is common for all instances of this class and its subclasses.

Parameters:

obj - the object the given Environment is for

env - the Environment to store

Throws:

java.lang.NullPointerException - if one of the parameters is null

removeEnvironment

public static void removeEnvironment(java.lang.Object obj)

Removing a registered Environment. If the given object is not known to the EnvironmentProvider the method does nothing.

Parameters:

obj - the object thats Environment should be removed