org.apache.reef.tang.implementation.java

Class InjectorImpl

java.lang.Object

org.apache.reef.tang.implementation.java.InjectorImpl

All Implemented Interfaces:

Injector

public class InjectorImpl
extends Object
implements Injector

Constructor Summary

Constructors

Constructor and Description
InjectorImpl(Configuration c)

Method Summary

Methods

Modifier and Type	Method and Description
<T> void	bindAspect(Aspect a) Binds a TANG Aspect to this injector.
<T> void	bindVolatileInstance(Class<T> cl, T o) Binds the given object to the class.
<T> void	bindVolatileParameter(Class<? extends Name<T>> cl, T o)
Injector	forkInjector()
Injector	forkInjector(Configuration... configurations) Create a copy of this Injector that inherits the instances that were already created by this Injector, but reflects additional Configuration objects.
Aspect	getAspect() Allows InjectionFuture to tell the aspect when get() is invoked.
<T> InjectionPlan<T>	getInjectionPlan(Class<T> name)
InjectionPlan<?>	getInjectionPlan(Node n) Return an injection plan for the given class / parameter name.
InjectionPlan<?>	getInjectionPlan(String name)
<U> U	getInstance(Class<U> clazz) Gets an instance of iface, or the implementation that has been bound to it.
<U> U	getInstance(String clazz) Gets an instance of iface, or the implementation that has been bound to it.
<T> T	getNamedInstance(Class<? extends Name<T>> clazz) Gets the value stored for the given named parameter.
<T> T	getNamedParameter(Class<? extends Name<T>> clazz)
boolean	isInjectable(Class<?> clazz)
boolean	isInjectable(String name) Returns true if this Injector is able to instantiate the object named by name.
boolean	isParameterSet(Class<? extends Name<?>> name)
boolean	isParameterSet(String name)

Methods inherited from class java.lang.Object

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

Constructor Detail

InjectorImpl

public InjectorImpl(Configuration c)
             throws BindException

Throws:

BindException

Method Detail

getInjectionPlan

public InjectionPlan<?> getInjectionPlan(Node n)

Return an injection plan for the given class / parameter name.

Parameters:

n - The name of an injectable class or interface, or a NamedParameter.

Returns:

Throws:

NameResolutionException

getInjectionPlan

public InjectionPlan<?> getInjectionPlan(String name)
                                  throws NameResolutionException

Specified by:

getInjectionPlan in interface Injector

Throws:

NameResolutionException

getInjectionPlan

public <T> InjectionPlan<T> getInjectionPlan(Class<T> name)

Specified by:

getInjectionPlan in interface Injector

isInjectable

public boolean isInjectable(String name)
                     throws NameResolutionException

Description copied from interface: Injector

Returns true if this Injector is able to instantiate the object named by name.

Specified by:

isInjectable in interface Injector

Parameters:

name - a name of object

Returns:

whether the name is injectable

Throws:

NameResolutionException

isInjectable

public boolean isInjectable(Class<?> clazz)

Specified by:

isInjectable in interface Injector

isParameterSet

public boolean isParameterSet(String name)
                       throws NameResolutionException

Specified by:

isParameterSet in interface Injector

Throws:

NameResolutionException

isParameterSet

public boolean isParameterSet(Class<? extends Name<?>> name)
                       throws BindException

Specified by:

isParameterSet in interface Injector

Throws:

BindException

getInstance

public <U> U getInstance(Class<U> clazz)
              throws InjectionException

Description copied from interface: Injector

Gets an instance of iface, or the implementation that has been bound to it. If an instance has already been created in this (or a parent) scope, then the existing instance will be returned. Otherwise, a new instance will be returned, and registered in the current scope.

Specified by:

getInstance in interface Injector

Type Parameters:

U - a type

Parameters:

clazz - an interface

Returns:

an instance

Throws:

InjectionException - if it fails to find corresponding class

getInstance

public <U> U getInstance(String clazz)
              throws InjectionException,
                     NameResolutionException

Description copied from interface: Injector

Gets an instance of iface, or the implementation that has been bound to it. If an instance has already been created in this (or a parent) scope, then the existing instance will be returned. Otherwise, a new instance will be returned, and registered in the current scope.

Specified by:

getInstance in interface Injector

Type Parameters:

U - a type

Parameters:

clazz - a name of interface

Returns:

an instance

Throws:

InjectionException - if it fails to find corresponding class

NameResolutionException - if name resolution fails

getNamedInstance

public <T> T getNamedInstance(Class<? extends Name<T>> clazz)
                   throws InjectionException

Description copied from interface: Injector

Gets the value stored for the given named parameter.

Specified by:

getNamedInstance in interface Injector

Type Parameters:

T - a type

Parameters:

clazz - the name of interface

Returns:

an Instance of the class configured as the implementation for the given interface class.

Throws:

InjectionException - if name resolution fails

getNamedParameter

public <T> T getNamedParameter(Class<? extends Name<T>> clazz)
                    throws InjectionException

Throws:

InjectionException

bindVolatileInstance

public <T> void bindVolatileInstance(Class<T> cl,
                            T o)
                          throws BindException

Description copied from interface: Injector

Binds the given object to the class. Note that this only affects objects created by the returned Injector and its children. Also, like all Injectors, none of those objects can be serialized back to a configuration file).

Specified by:

bindVolatileInstance in interface Injector

Type Parameters:

T - a type

Parameters:

cl - an interface cass

o - an instance

Throws:

BindException - when trying to re-bind

bindVolatileParameter

public <T> void bindVolatileParameter(Class<? extends Name<T>> cl,
                             T o)
                           throws BindException

Specified by:

bindVolatileParameter in interface Injector

Throws:

BindException

forkInjector

public Injector forkInjector()

Specified by:

forkInjector in interface Injector

forkInjector

public Injector forkInjector(Configuration... configurations)
                      throws BindException

Description copied from interface: Injector

Create a copy of this Injector that inherits the instances that were already created by this Injector, but reflects additional Configuration objects. This can be used to create trees of Injectors that obey hierarchical scoping rules.

Except for the fact that the child Injector will have references to this injector's instances, the returned Injector is equivalent to the one you would get by using ConfigurationBuilder to build a merged Configuration, and then using the merged Configuration to create an Injector. Injectors returned by ConfigurationBuilders are always independent, and never share references to the same instances of injected objects.

Specified by:

forkInjector in interface Injector

Parameters:

configurations - configurations

Returns:

an injector

Throws:

BindException - If any of the configurations conflict with each other, or the existing Injector's Configuration.

bindAspect

public <T> void bindAspect(Aspect a)
                throws BindException

Description copied from interface: Injector

Binds a TANG Aspect to this injector. Tang Aspects interpose on each injection performed by an injector, and return an instance of their choosing.

A given aspect will be invoked once for each object that Tang injects, and aspects will be copied in a way that mirrors the scoping that Tang creates at runtime.

Specified by:

bindAspect in interface Injector

Type Parameters:

T - a type

Parameters:

a - aspect

Throws:

BindException - if there exists a bound aspect already

getAspect

public Aspect getAspect()

Description copied from interface: Injector

Allows InjectionFuture to tell the aspect when get() is invoked. Package private.

Specified by:

getAspect in interface Injector

Returns:

the aspect