org.omnifaces.util

Class Beans

java.lang.Object

org.omnifaces.util.Beans

@Typed
public final class Beans
extends Object

Collection of utility methods for the CDI API that are mainly shortcuts for obtaining stuff from the BeanManager.

Usage

Some examples:

 // Get the CDI managed bean reference (proxy) of the given bean class.
 SomeBean someBean = Beans.getReference(SomeBean.class);

 // Get the CDI managed bean instance (actual) of the given bean class.
 SomeBean someBean = Beans.getInstance(SomeBean.class);

 // Get all currently active CDI managed bean instances in the session scope.
 Map<Object, String> activeSessionScopedBeans = Beans.getActiveInstances(SessionScope.class);

 // Destroy any currently active CDI managed bean instance of given bean class.
 Beans.destroy(SomeBean.class);
 

The "native" CDI way would otherwise look like this:

 // Get the CDI managed bean reference (proxy) of the given bean class.
 Set<Bean<?>> beans = beanManager.getBeans(SomeBean.class);
 Bean<SomeBean> bean = (Bean<SomeBean>) beanManager.resolve(beans);
 CreationalContext<SomeBean> context = beanManager.createCreationalContext(bean);
 SomeBean someBean = (SomeBean) beanManager.getReference(bean, SomeBean.class, context);
 

If you need a dependency-free way of obtaining the CDI managed bean reference (e.g. when you want to write code which should also run on Tomcat), use BeanManager enum instead.

Since:

1.6.1

Author:

Bauke Scholtz

See Also:

BeansLocal

Method Summary

Modifier and Type	Method and Description
static <T> void	destroy(Bean<T> bean) Destroy the currently active instance of the given CDI managed bean representation.
static <T> void	destroy(Class<T> beanClass) Destroy the currently active instance of the given CDI managed bean class.
static <S extends NormalScope> Map<Object,String>	getActiveInstances(Class<S> scope) Returns all active CDI managed bean instances in the given CDI managed bean scope.
static <A extends Annotation> A	getAnnotation(Annotated annotated, Class<A> annotationType) Get program element annotation of a certain annotation type.
static InjectionPoint	getCurrentInjectionPoint(CreationalContext<?> creationalContext) Gets the current injection point when called from a context where injection is taking place (e.g.
static <T> T	getInstance(Bean<T> bean, boolean create) Returns the CDI managed bean instance (actual) of the given bean representation and creates one if one doesn't exist and create argument is true, otherwise don't create one and return null if there's no current instance.
static <T> T	getInstance(Class<T> beanClass) Returns the CDI managed bean instance (actual) of the given bean class and creates one if one doesn't exist.
static <T> T	getInstance(Class<T> beanClass, boolean create) Returns the CDI managed bean instance (actual) of the given bean class and creates one if one doesn't exist and create argument is true, otherwise don't create one and return null if there's no current instance.
static BeanManager	getManager() Returns the CDI bean manager.
static <T> T	getReference(Bean<T> bean) Returns the CDI managed bean reference (proxy) of the given bean representation.
static <T> T	getReference(Class<T> beanClass) Returns the CDI managed bean reference (proxy) of the given bean class.
static <T> Bean<T>	resolve(Class<T> beanClass) Returns the CDI managed bean representation of the given bean class.

Methods inherited from class java.lang.Object

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

Method Detail

getManager

public static BeanManager getManager()

Returns the CDI bean manager.

Returns:

The CDI bean manager.

Since:

2.0

See Also:

BeanManager.get()

resolve

public static <T> Bean<T> resolve(Class<T> beanClass)

Returns the CDI managed bean representation of the given bean class.

Type Parameters:

T - The generic CDI managed bean type.

Parameters:

beanClass - The CDI managed bean class.

Returns:

The CDI managed bean representation of the given bean class, or null if there is none.

See Also:

BeanManager.getBeans(String), BeanManager.resolve(java.util.Set)

getReference

public static <T> T getReference(Class<T> beanClass)

Returns the CDI managed bean reference (proxy) of the given bean class. Note that this actually returns a client proxy and the underlying actual instance is thus always auto-created.

Type Parameters:

T - The expected return type.

Parameters:

beanClass - The CDI managed bean class.

Returns:

The CDI managed bean reference (proxy) of the given class, or null if there is none.

See Also:

resolve(Class), getReference(Bean)

getReference

public static <T> T getReference(Bean<T> bean)

Returns the CDI managed bean reference (proxy) of the given bean representation. Note that this actually returns a client proxy and the underlying actual instance is thus always auto-created.

Type Parameters:

T - The expected return type.

Parameters:

bean - The CDI managed bean representation.

Returns:

The CDI managed bean reference (proxy) of the given bean, or null if there is none.

See Also:

BeanManager.createCreationalContext(javax.enterprise.context.spi.Contextual), BeanManager.getReference(Bean, java.lang.reflect.Type, javax.enterprise.context.spi.CreationalContext)

getInstance

public static <T> T getInstance(Class<T> beanClass)

Returns the CDI managed bean instance (actual) of the given bean class and creates one if one doesn't exist.

Type Parameters:

T - The expected return type.

Parameters:

beanClass - The CDI managed bean class.

Returns:

The CDI managed bean instance (actual) of the given bean class, or null if there is none.

Since:

1.8

See Also:

getInstance(Class, boolean)

getInstance

public static <T> T getInstance(Class<T> beanClass,
                                boolean create)

Returns the CDI managed bean instance (actual) of the given bean class and creates one if one doesn't exist and create argument is true, otherwise don't create one and return null if there's no current instance.

Type Parameters:

T - The expected return type.

Parameters:

beanClass - The CDI managed bean class.

create - Whether to create create CDI managed bean instance if one doesn't exist.

Returns:

The CDI managed bean instance (actual) of the given bean class, or null if there is none and/or the create argument is false.

Since:

1.7

See Also:

resolve(Class), getInstance(Bean, boolean)

getInstance

public static <T> T getInstance(Bean<T> bean,
                                boolean create)

Returns the CDI managed bean instance (actual) of the given bean representation and creates one if one doesn't exist and create argument is true, otherwise don't create one and return null if there's no current instance.

Type Parameters:

T - The expected return type.

Parameters:

bean - The CDI managed bean representation.

create - Whether to create create CDI managed bean instance if one doesn't exist.

Returns:

The CDI managed bean instance (actual) of the given bean, or null if there is none and/or the create argument is false.

Since:

1.7

See Also:

BeanManager.getContext(Class), BeanManager.createCreationalContext(javax.enterprise.context.spi.Contextual), Context.get(javax.enterprise.context.spi.Contextual, javax.enterprise.context.spi.CreationalContext)

getActiveInstances

public static <S extends NormalScope> Map<Object,String> getActiveInstances(Class<S> scope)

Returns all active CDI managed bean instances in the given CDI managed bean scope. The map key represents the active CDI managed bean instance and the map value represents the CDI managed bean name, if any.

Type Parameters:

S - The generic CDI managed bean scope type.

Parameters:

scope - The CDI managed bean scope, e.g. RequestScoped.class.

Returns:

All active CDI managed bean instances in the given CDI managed bean scope.

Since:

1.7

See Also:

BeanManager.getBeans(String), BeanManager.getContext(Class), Context.get(javax.enterprise.context.spi.Contextual)

destroy

public static <T> void destroy(Class<T> beanClass)

Destroy the currently active instance of the given CDI managed bean class.

Type Parameters:

T - The generic CDI managed bean type.

Parameters:

beanClass - The CDI managed bean class.

Since:

2.0

See Also:

resolve(Class), destroy(Bean)

destroy

public static <T> void destroy(Bean<T> bean)

Destroy the currently active instance of the given CDI managed bean representation.

Type Parameters:

T - The generic CDI managed bean type.

Parameters:

bean - The CDI managed bean representation.

Throws:

IllegalArgumentException - When the given CDI managed bean type is actually not put in an alterable context.

Since:

2.0

See Also:

BeanManager.getContext(Class), AlterableContext.destroy(javax.enterprise.context.spi.Contextual)

getAnnotation

public static <A extends Annotation> A getAnnotation(Annotated annotated,
                                                     Class<A> annotationType)

Get program element annotation of a certain annotation type. The difference with Annotated.getAnnotation(Class) is that this method will recursively search inside all Stereotype annotations.

Type Parameters:

A - The generic annotation type.

Parameters:

annotated - A Java program element that can be annotated.

annotationType - The class of the annotation type.

Returns:

The program element annotation of the given annotation type if it could be found, otherwise null.

Since:

1.8

getCurrentInjectionPoint

public static InjectionPoint getCurrentInjectionPoint(CreationalContext<?> creationalContext)

Gets the current injection point when called from a context where injection is taking place (e.g. from a producer).

This is mostly intended to be used from within a dynamic producer Bean. For a "regular" producer (using Produces) an InjectionPoint can either be injected into the bean that contains the producer method, or directly provided as argument of said method.

Parameters:

creationalContext - a CreationalContext used to manage objects with a Dependent scope

Returns:

the current injection point when called from a context where injection is taking place (e.g. from a producer)