net.sf.jguiraffe.di.impl

Class DefaultBeanContext

java.lang.Object

net.sf.jguiraffe.di.impl.DefaultBeanContext

All Implemented Interfaces:

BeanContext

public class DefaultBeanContext
extends Object
implements BeanContext

A default implementation of the BeanContext interface.

This class allows full access to all beans defined in a hierarchy of BeanStores. Dependencies are dynamically resolved and injected.

The class is thread-safe. When operating on a bean store hierarchy it implements transactional behavior as described in the documentation to the BeanStore interface, i.e. if two threads try to access a BeanProvider concurrently, one of the will be suspended until the other one has resolved all of its dependencies. This enables concurrent, synchronized access to bean stores in a read-only manner. However the bean stores should not be written at the same time.

Version:

$Id: DefaultBeanContext.java 205 2012-01-29 18:29:57Z oheger $

Author:

Oliver Heger

Constructor Summary

Constructors

Constructor and Description
DefaultBeanContext() Creates a new instance of DefaultBeanContext.
DefaultBeanContext(BeanStore defStore) Creates a new instance of DefaultBeanContext and sets the default bean store.

Method Summary

Modifier and Type	Method and Description
void	addBeanCreationListener(BeanCreationListener l) Adds the specified BeanCreationListener to this context.
Set<Class<?>>	beanClasses() Obtains a list of the classes of the beans defined in the default bean store.
Set<Class<?>>	beanClasses(BeanStore store) Obtains a list of the classes of the beans defined in the given store and its parents.
String	beanNameFor(BeanProvider beanProvider) Searches for the specified BeanProvider in the accessible bean stores (starting with the default bean store) and the returns the name, under which it is registered.
String	beanNameFor(BeanProvider beanProvider, BeanStore store) Searches for the specified BeanProvider in the accessible bean stores (starting with the specified bean store) and the returns the name, under which it is registered.
Set<String>	beanNames() Returns a set with the names of the beans defined in the default bean store.
Set<String>	beanNames(BeanStore store) Returns a set with the names of the beans defined in the given bean store (or its parent).
void	close() Closes this BeanContext.
boolean	containsBean(Class<?> beanClass) Tests whether a bean with the given bean class can be found in the default bean store.
boolean	containsBean(Class<?> beanClass, BeanStore store) Tests whether a bean with the given class can be found in the specified bean store.
boolean	containsBean(String name) Tests whether a bean with the given name can be found in the default store.
boolean	containsBean(String name, BeanStore store) Tests whether a bean with the given name can be found in the specified bean store.
<T> T	getBean(Class<T> beanCls) Returns the bean with the specified class from the default bean store.
<T> T	getBean(Class<T> beanCls, BeanStore store) Returns the bean with the specified class from the given bean store.
protected Object	getBean(Dependency dependency, BeanStore store) Obtains the bean from the BeanProvider specified by the given Dependency.
Object	getBean(String name) Returns the bean with the specified name from the default store.
Object	getBean(String name, BeanStore store) Returns the bean with the specified name from the given bean store.
ClassLoaderProvider	getClassLoaderProvider() Returns the ClassLoaderProvider used by this bean context.
BeanStore	getDefaultBeanStore() Returns the default bean store.
void	removeBeanCreationListener(BeanCreationListener l) Removes the specified BeanCreationListener from this context.
void	setClassLoaderProvider(ClassLoaderProvider classLoaderProvider) Sets the ClassLoaderProvider to be used by this bean context.
void	setDefaultBeanStore(BeanStore store) Sets the default bean store.
protected void	waitForTx(BeanStore root) Waits at the specified bean store until the current transaction finishes.

Methods inherited from class java.lang.Object

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

Constructor Detail

DefaultBeanContext

public DefaultBeanContext()

Creates a new instance of DefaultBeanContext.

DefaultBeanContext

public DefaultBeanContext(BeanStore defStore)

Creates a new instance of DefaultBeanContext and sets the default bean store. This parameter is optional. If no BeanStore is provided, a default store must be set later or only methods can be used that expect a store as argument.

Parameters:

defStore - the default bean store

Method Detail

getClassLoaderProvider

public ClassLoaderProvider getClassLoaderProvider()

Returns the ClassLoaderProvider used by this bean context.

Specified by:

getClassLoaderProvider in interface BeanContext

Returns:

the ClassLoaderProvider

See Also:

setClassLoaderProvider(ClassLoaderProvider)

setClassLoaderProvider

public void setClassLoaderProvider(ClassLoaderProvider classLoaderProvider)

Sets the ClassLoaderProvider to be used by this bean context. The ClassLoaderProvider is needed when dependencies to beans are to be resolved that specified by class names. When a new DefaultBeanContext instance is created, a default ClassLoaderProvider is set. It is then possible to change this object using this method.

Specified by:

setClassLoaderProvider in interface BeanContext

Parameters:

classLoaderProvider - the new ClassLoaderProvider (must not be null)

Throws:

IllegalArgumentException - if the parameter is null

beanClasses

public Set<Class<?>> beanClasses()

Obtains a list of the classes of the beans defined in the default bean store.

Specified by:

beanClasses in interface BeanContext

Returns:

the classes of the defined beans

beanClasses

public Set<Class<?>> beanClasses(BeanStore store)

Obtains a list of the classes of the beans defined in the given store and its parents.

Specified by:

beanClasses in interface BeanContext

Parameters:

store - the store to start from

Returns:

the classes of the defined beans

beanNames

public Set<String> beanNames()

Returns a set with the names of the beans defined in the default bean store.

Specified by:

beanNames in interface BeanContext

Returns:

the names of the defined beans

beanNames

public Set<String> beanNames(BeanStore store)

Returns a set with the names of the beans defined in the given bean store (or its parent).

Specified by:

beanNames in interface BeanContext

Parameters:

store - the bean store

Returns:

a set with the names of the defined beans

containsBean

public boolean containsBean(String name)

Tests whether a bean with the given name can be found in the default store.

Specified by:

containsBean in interface BeanContext

Parameters:

name - the name of the bean

Returns:

a flag whether this bean can be found

containsBean

public boolean containsBean(String name,
                            BeanStore store)

Tests whether a bean with the given name can be found in the specified bean store. null can be specified for both the name and the bean store; result will then be false.

Specified by:

containsBean in interface BeanContext

Parameters:

name - the name of the bean

store - the bean store

Returns:

a flag whether this bean can be found in this store

containsBean

public boolean containsBean(Class<?> beanClass)

Tests whether a bean with the given bean class can be found in the default bean store.

Specified by:

containsBean in interface BeanContext

Parameters:

beanClass - the class of the bean

Returns:

a flag whether this bean can be found

containsBean

public boolean containsBean(Class<?> beanClass,
                            BeanStore store)

Tests whether a bean with the given class can be found in the specified bean store. null can be specified for both the name and the bean store; result will then be false.

Specified by:

containsBean in interface BeanContext

Parameters:

beanClass - the class of the bean

store - the bean store

Returns:

a flag whether this bean can be found in this store

getBean

public Object getBean(String name)

Returns the bean with the specified name from the default store.

Specified by:

getBean in interface BeanContext

Parameters:

name - the name of the bean to retrieve

Returns:

the bean with this name

Throws:

InjectionException - if an error occurs

getBean

public Object getBean(String name,
                      BeanStore store)

Returns the bean with the specified name from the given bean store.

Specified by:

getBean in interface BeanContext

Parameters:

name - the name of the bean to retrieve

store - the bean store

Returns:

the bean with this name

Throws:

InjectionException - if an error occurs

getBean

public <T> T getBean(Class<T> beanCls)

Returns the bean with the specified class from the default bean store.

Specified by:

getBean in interface BeanContext

Type Parameters:

T - the type of the bean to be retrieved

Parameters:

beanCls - the class of the bean to be retrieved

Returns:

the bean with this class

Throws:

InjectionException - if an error occurs

getBean

public <T> T getBean(Class<T> beanCls,
                     BeanStore store)

Returns the bean with the specified class from the given bean store.

Specified by:

getBean in interface BeanContext

Type Parameters:

T - the type of the bean to be retrieved

Parameters:

beanCls - the class of the bean to be retrieved

store - the bean store

Returns:

the bean with this class

Throws:

InjectionException - if an error occurs

getDefaultBeanStore

public BeanStore getDefaultBeanStore()

Returns the default bean store.

Specified by:

getDefaultBeanStore in interface BeanContext

Returns:

the default bean store

beanNameFor

public String beanNameFor(BeanProvider beanProvider)

Searches for the specified BeanProvider in the accessible bean stores (starting with the default bean store) and the returns the name, under which it is registered.

Specified by:

beanNameFor in interface BeanContext

Parameters:

beanProvider - the BeanProvider in question

Returns:

the corresponding bean name or null if it cannot be resolved

See Also:

BeanContext.beanNameFor(BeanProvider, BeanStore)

beanNameFor

public String beanNameFor(BeanProvider beanProvider,
                          BeanStore store)

Searches for the specified BeanProvider in the accessible bean stores (starting with the specified bean store) and the returns the name, under which it is registered.

Specified by:

beanNameFor in interface BeanContext

Parameters:

beanProvider - the BeanProvider in question

store - the BeanStore

Returns:

the corresponding bean name or null if it cannot be resolved

close

public void close()

Closes this BeanContext. This is just an empty dummy implementation. There are no resources to be freed.

Specified by:

close in interface BeanContext

setDefaultBeanStore

public void setDefaultBeanStore(BeanStore store)

Sets the default bean store.

Specified by:

setDefaultBeanStore in interface BeanContext

Parameters:

store - the new default bean store

addBeanCreationListener

public void addBeanCreationListener(BeanCreationListener l)

Adds the specified BeanCreationListener to this context.

Specified by:

addBeanCreationListener in interface BeanContext

Parameters:

l - the listener to add (must not be null)

Throws:

IllegalArgumentException - if the listener is null

removeBeanCreationListener

public void removeBeanCreationListener(BeanCreationListener l)

Removes the specified BeanCreationListener from this context.

Specified by:

removeBeanCreationListener in interface BeanContext

Parameters:

l - the listener to be removed

getBean

protected Object getBean(Dependency dependency,
                         BeanStore store)

Obtains the bean from the BeanProvider specified by the given Dependency. This method is called by the other getBean() methods. It does the real work.

Parameters:

dependency - the dependency to be resolved

store - the current store

Returns:

the bean managed by the specified provider

Throws:

InjectionException - if an error occurs while resolving the dependency

waitForTx

protected void waitForTx(BeanStore root)
                  throws InterruptedException

Waits at the specified bean store until the current transaction finishes. This method is called when a transaction affects a bean provider that is already locked by another transaction. In this case this other transaction has to finish first. This implementation calls wait() on the given bean store.

Parameters:

root - the root bean store

Throws:

InterruptedException - if the thread is interrupted