Commands

Commands are tokens defined in template layout files that describe what to do with a specific region of the layout. The following commands are built in: <ul> <li> include(‘key’) – where key name refers to a JSON property that refers to an HTML fragement that is included. The sub portions of a page may be static HTML files, JSP files, or references on another server that are loading using a HTTP client. <pre> { “id” : “blueprints-css”, “template” : “templates/bp-2-column-base.html”, “properties” : { “header” : { “type” : “include”, “value” : “/header.html” }, “sidebar” : { “type” : “include”, “value” : “/sidebar.html” }, “footer” : { “type” : “include”, “value” : “/footer.html” } } } </pre> A base template is much like an abstract class in Java. In the example about you can create a base template for all your pages and then create children that provide the differences. <pre> { “id” : “main”, “extends” : “blueprints-css”, “properties” : { “title” : {"type" : “string”, “value” : “Welcome to Acme Templates”}, “body” : { “type” : “include”, “value” : “/main.html”} } } </pre> A template can extend any number of other templates using a comma separated list. Template properties in the base template override ancestor properties. Properties in closer descendants override those of older descendants. </li> <li> insert(‘key’) – where key refers to a JSON property that defines static text and may include references objects on the server. A good example of the insert command is for providing titles for different pages. An example of a reference to an object in the ServletContext follows: <pre> “footer” : {"type" : “string”, “value” : “${context.serverName}”}, </pre> The format for expressions is : ${scope.property) or ${scope.bean.property} scopes are : <ul> <li>session – HttpSession <li> request – HttpServletRequest, <li>context – ServletContext <li>none – Protorabbit Context – This context is analogous to the HttpServletRequest but is not tied to the javax.servlet API. </ul> Protorabbit will first look for an object following the scope. All sub objects should have public getter methods. For example if you have a cart object in your HttpSession scope with Java object like: <pre> public class Cart { … public double getTotal() { … } } </pre> you can reference the property using: <pre> ${session.cart.total} </pre> All properties are evaluated to Strings so you will need to make sure to take care of any formatting internally. </ul> Custom commands may be provided by implementing a simple interface and placing the class in the classpath. <pre> package mycommand; import java.io.IOException; public class HelloCommand extends BaseCommand { @Override public void doProcess(OutputStream out) throws IOException { String message = "hello "; if (params.length > 0) { message += params[0].getValue(); } out.write(message.getBytes()); } } </pre> To use the command include the package name + class name (excluding Command) in your layout file. Example: <pre> <^ mycommand.Hello("Proto Rabbit") ^> </pre> 2009-11-25T20:15:37-08:00 206211 commands

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Commands

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