Specifications

5ADOBE FLEX 3
Building and Deploying Adobe Flex 3 Applications
Struts is based on a Model-View-Controller (MVC) architecture, with a focus on the controller part of the MVC
architecture. In addition, it provides JSP tag libraries to help you create the view in a traditional JSP/HTML
environment.
Configure phase
Before you write your first line of application code, or before you deploy an application, you must ensure that you
configure your environment correctly. Configuration is a broad term and encompasses several different tasks.
For example, you must configure your development and deployment environments to ensure that your appli-
cation can access the required resources and data services. If your application requires access to a web service,
ensure that your application has the correct access rights to the web service. If you application runs outside a
firewall, ensure that it can access resources inside the firewall.
The following sections contain an overview of configuration tasks.
About run-time configuration
Most run-time configuration has to do with configuring access to remote data services, such as web services. For
example, during application development, you run your application behind a firewall, where the application has
access to all necessary resources and data services. However, when you deploy the application, you must ensure
that an executing application can still access the necessary resources when the application runs outside of the
firewall.
One configuration issue for Flex SDK applications is the placement of a crossdomain.xml file. For security, by
default Flash Player does not allow an application to access a remote data service from a domain other than the
domain from which the application was served. Therefore, a server that hosts a data service must be in the same
domain as the server hosting your application, or the remote server must define a crossdomain.xml file. A cross-
domain.xml file is an XML file that provides a way for a server to indicate that its data and documents are available
to SWF files served from specific domains, or from all domains. By default, place the crossdomain.xml at the root
directory of the server that is serving the data.
Flex SDK does not include a server-side proxy for handling data service requests. Therefore, you must ensure that
you configure data services for direct access by your application, or make data service requests through your own
proxy server.