Package io.avaje.inject

Interface BeanContext

All Superinterfaces:

AutoCloseable, Closeable

public interface BeanContext
extends Closeable

Holds beans created by dependency injection.

The beans have singleton scope, support lifecycle methods for postConstruct and preDestroy and are created (wired) via dependency injection.

Create a BeanContext

We can programmatically create a BeanContext via BeanContextBuilder.

   // create a BeanContext ...

   try (BeanContext context = new BeanContextBuilder()
     .build()) {

     CoffeeMaker coffeeMaker = context.getBean(CoffeeMaker.class);
     coffeeMaker.makeIt()
   }

 

Implicitly used

The BeanContext is implicitly used by SystemContext. It will be created as needed and a shutdown hook will close the underlying BeanContext on JVM shutdown.

   // BeanContext created as needed under the hood

   CoffeeMaker coffeeMaker = SystemContext.getBean(CoffeeMaker.class);
   coffeeMaker.brew();

 

Method Summary

Modifier and Type	Method	Description
<T> BeanEntry<T>	candidate(Class<T> type, String name)	Return the wiring candidate bean with name and priority.
void	close()	Close the context firing any @PreDestroy methods.
<T> T	getBean(Class<T> type)	Return a single bean given the type.
<T> T	getBean(Class<T> type, String name)	Return a single bean given the type and name.
<T> List<T>	getBeans(Class<T> interfaceType)	Return the list of beans that implement the interface.
<T> List<T>	getBeansByPriority(Class<T> interfaceType)	Return the list of beans that implement the interface sorting by priority (ignoring any Priority annotation).
List<Object>	getBeansWithAnnotation(Class<?> annotation)	Return the list of beans that have an annotation.
String[]	getDependsOn()	Return the names of modules this bean context depends on.
String	getName()	Return the module name of the bean context.
String[]	getProvides()	Return the names of module features this bean context provides.
<T> List<T>	sortByPriority(List<T> list)	Sort the beans by javax.annotation.Priority annotation.
void	start()	Start the context firing any @PostConstruct methods.

Method Detail

getName

String getName()

Return the module name of the bean context.

See Also:

ContextModule

getProvides

String[] getProvides()

Return the names of module features this bean context provides.

See Also:

ContextModule

getDependsOn

String[] getDependsOn()

Return the names of modules this bean context depends on.

See Also:

ContextModule

getBean

<T> T getBean(Class<T> type)

Return a single bean given the type.

   CoffeeMaker coffeeMaker = beanContext.getBean(CoffeeMaker.class);
   coffeeMaker.brew();

 

Parameters:

type - an interface or bean type

getBean

<T> T getBean(Class<T> type,
              String name)

Return a single bean given the type and name.

   Heater heater = beanContext.getBean(Heater.class, "electric");
   heater.heat();

 

Parameters:

type - an interface or bean type

name - the name qualifier of a specific bean

candidate

<T> BeanEntry<T> candidate(Class<T> type,
                           String name)

Return the wiring candidate bean with name and priority.

getBeansWithAnnotation

List<Object> getBeansWithAnnotation(Class<?> annotation)

Return the list of beans that have an annotation.

   // e.g. register all controllers with web a framework
   // .. where Controller is an annotation on the beans

   List<Object> controllers = SystemContext.getBeansWithAnnotation(Controller.class);

 

The classic use case for this is registering controllers or routes to web frameworks like Sparkjava, Javlin, Rapidoid etc.

Parameters:

annotation - An annotation class.

getBeans

<T> List<T> getBeans(Class<T> interfaceType)

Return the list of beans that implement the interface.

   // e.g. register all routes for a web framework

   List<WebRoute> routes = SystemContext.getBeans(WebRoute.class);

 

Parameters:

interfaceType - An interface class.

getBeansByPriority

<T> List<T> getBeansByPriority(Class<T> interfaceType)

Return the list of beans that implement the interface sorting by priority (ignoring any Priority annotation).

sortByPriority

<T> List<T> sortByPriority(List<T> list)

Sort the beans by javax.annotation.Priority annotation.

Parameters:

list - The beans to sort by priority

Returns:

A new list of beans sorted by priority

start

void start()

Start the context firing any @PostConstruct methods.

close

void close()

Close the context firing any @PreDestroy methods.

Specified by:

close in interface AutoCloseable

Specified by:

close in interface Closeable