THIS IS A TEST INSTANCE. ALL YOUR CHANGES WILL BE LOST!!!!
Injection
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Injection is Tapestry's way of making a dependency – such as a resource, asset, component, block or service – available in a page, component, mixin or service class.
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Injection is a key concept in Tapestry, and it is used in several different but related ways.
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, listed below.
Injection in Tapestry IOC Services
Main Article: Tapestry Ioc Overview Injection in Detail
The Tapestry IoC container makes use of injection primarily through constructors and via parameters to service builder methods.
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For field type Block, the value of the Inject annotation is the id of the <t:block> element within the component's template. Normally, the id of the block is determined from the field name (after stripping out any leading "_" and "$" characters):
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@Inject
private Block foo;
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Where that is not appropriate, an @Id annotation can be supplied:
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@Inject
@Id("bar")
private Block barBlock;
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A very common example occurs when a component needs access to its resources. The component can define a field of the appropriate type and use the @Inject annotation without a value:
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@Inject
private ComponentResources resources;
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When the @Path annotation is also present, then the injected value (relative to the component) will be a localized asset.
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@Inject
@Path("context:images/top_banner.png")
private Asset banner;
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Here, a custom EmployeeService service is injected, but any custom or built-in service may be injected in the same way.
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@Inject
private EmployeeService employeeService;
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A large number of services are provided by Tapestry. See the following packages:
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* [Core Services|http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/services/package-summary.html]
* [AJAX Services|http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/services/ajax/package-summary.html]
* [Assets Services|http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/services/assets/package-summary.html]
* [Dynamic Component Services|http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/services/dynamic/package-summary.html]
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* [JavaScript Services|http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/services/javascript/package-summary.html]
* [Link Transformation Services|http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/services/linktransform/package-summary.html]
* [Message Services|http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/services/messages/package-summary.html]
* [Component Metadata Services|http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/services/meta/package-summary.html]
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* [Page Loading Services|http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/services/pageload/package-summary.html]
* [Security Services|http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/services/security/package-summary.html]
* [Template Services|http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/services/templates/package-summary.html]
* [Class Transformation Services|http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/services/transform/package-summary.html]
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* [Tapestry IOC Services|http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/ioc/services/package-summary.html]
* [Tapestry IOC Cron Services|http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/ioc/services/cron/package-summary.html]
* [Kaptcha Services|http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/kaptcha/services/package-summary.html]
* [File Upload Services|http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/upload/services/package-summary.html]
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Explicit Service Injection
Here, a specific object is requested. A @Service annotation is used to identify the service name.
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@Inject
@Service("Request")
private Request request;
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