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exported from angular2/di
defined in angular2/src/di/injector.ts (line 27)
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A dependency injection container used for resolving dependencies.
An `Injector` is a replacement for a `new` operator, which can automatically resolve the
constructor dependencies.
In typical use, application code asks for the dependencies in the constructor and they are
resolved by the `Injector`.
## Example:
Suppose that we want to inject an `Engine` into class `Car`, we would define it like this:
```javascript
class Engine {
}
class Car {
constructor(@Inject(Engine) engine) {
}
}
```
Next we need to write the code that creates and instantiates the `Injector`. We then ask for the
`root` object, `Car`, so that the `Injector` can recursively build all of that object's
dependencies.
```javascript
main() {
var injector = Injector.resolveAndCreate([Car, Engine]);
// Get a reference to the `root` object, which will recursively instantiate the tree.
var car = injector.get(Car);
}
```
Notice that we don't use the `new` operator because we explicitly want to have the `Injector`
resolve all of the object's dependencies automatically.
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h2 Members
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h3 constructor
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constructor(_bindings: List<ResolvedBinding>, _parent: Injector, _defaultBindings: boolean)
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h3 parent
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Direct parent of this injector.
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h3 get
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get(token)
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Retrieves an instance from the injector.
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h3 getOptional
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getOptional(token)
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Retrieves an instance from the injector.
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h3 asyncGet
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asyncGet(token)
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Retrieves an instance from the injector asynchronously. Used with asynchronous bindings.
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h3 resolveAndCreateChild
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resolveAndCreateChild(bindings: List<Type | Binding | List<any>>)
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Creates a child injector and loads a new set of bindings into it.
A resolution is a process of flattening multiple nested lists and converting individual
bindings into a list of ResolvedBindings. The resolution can be cached by `resolve`
for the Injector for performance-sensitive code.
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h3 createChildFromResolved
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createChildFromResolved(bindings: List<ResolvedBinding>)
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Creates a child injector and loads a new set of ResolvedBindings into it.