7: Setting the Configuration in Java

Print QR Code in Java 7: Setting the Configuration

handler: Fully qualified Java class name for this exception handler The default is orgapachestrutsactionExceptionHandler key: The key to use with this handler s message resource bundle that will retrieve the error message template for this exception path: The module-relative URI to the resource that completes the request and response if this exception occurs scope: The context (request or session) that accesses the ActionError object for this exception The default is request type: Fully qualified Java class name of the exception type to register with this handler Here is an example of the tag s use:

<global-exceptions> <exception bundle= ApplicationResources key= errorRuntimeException path= /baderrorjsp handler= dummiesstrutsmusicCustomExceptionHandler type= javalangRuntimeException /> </global-exceptions >

The example describes one global exception of type RuntimeException that supplies a message based in the errorRuntimeException resource bundle key The error is handled by a specialized exception handler class, CustomExceptionHandler The destination is a custom error page named baderrorjsp

Global forwards define a set of ActionForward objects available to all Action objects as a return value Any ActionForward of the same name that is defined in an <action> tag overrides the global ActionForward The tag for inserting global forwards is <global-forwards> The DTD syntax for the tag is

<!ELEMENT global-forwards (forward*)> <!ELEMENT forward (icon , display-name , description , set-property*)> <!ATTLIST forward className %ClassName; #IMPLIED> <!ATTLIST forward contextRelative %Boolean; #IMPLIED> <!ATTLIST forward name CDATA #REQUIRED> <!ATTLIST forward path %RequestPath; #REQUIRED> <!ATTLIST forward redirect %Boolean; #IMPLIED>

The DTD syntax for the <global-forwards> tag has the following properties:

<forward>: Defines ActionForward The attributes of the tag follow:

className: Fully qualified Java class name of ActionForward subclass to use for this object The default is orgapachestruts actionActionForward contextRelative: Set this to true if, in a modular application, the path attribute starts with a slash (/) and should be considered rel ative to the entire Web application rather than the module The default is false name: The unique identifier for this forward Referenced by the Action object at runtime to select by its logical name the resource that should complete the request/response path: The module-relative or context-relative path to the resources that this ActionForward encapsulates If the path is context-relative when used in a modular application, set the contextRelative attribute to true This value should begin with a slash (/) character redirect: Set to true if a redirect instruction should be issued to the user-agent so that a new request is issued for this forward s resource If true, the sendRedirect method of HttpServlet Response is called If false, the forward method of Request Dispatcher is called instead The default is false An example of the tag s use is

This simple example sets up a global forward of the name logon that for wards control to the resource on the path /logonjsp

Action mappings describe a set of ActionMapping objects Each Action Mapping object associates an Action object with a path and various other attributes Exactly one ActionMapping is represented by an action tag

The tag for inserting actions is <action-mappings> The DTD syntax for the tag is shown here:

<!ELEMENT action (icon , display-name , description , set-property*, exception*, forward*)> <!ATTLIST action attribute %BeanName; #IMPLIED> <!ATTLIST action className %ClassName; #IMPLIED> <!ATTLIST action forward %RequestPath; #IMPLIED> <!ATTLIST action include %RequestPath; #IMPLIED> <!ATTLIST action input %RequestPath; #IMPLIED> <!ATTLIST action name %BeanName; #IMPLIED> <!ATTLIST action parameter CDATA #IMPLIED> <!ATTLIST action path %RequestPath; #REQUIRED> <!ATTLIST action prefix CDATA #IMPLIED> <!ATTLIST action roles CDATA #IMPLIED> <!ATTLIST action scope %RequestScope; #IMPLIED> <!ATTLIST action suffix CDATA #IMPLIED> <!ATTLIST action type %ClassName; #IMPLIED> <!ATTLIST action unknown %Boolean; #IMPLIED> <!ATTLIST action validate %Boolean; #IMPLIED>

The <action-mappings> tag uses the following attributes:

<action-mappings>: Defines the beginning of a set of actions <action>: Represents one ActionMapping object The attributes of the

tag follow: attribute: Name of the request-scope or session-scope attribute that accesses the ActionForm bean, if it s other than the bean s specified name This attribute is optional if name is specified but otherwise is not valid className: The fully qualified Java class name of the Action Mapping subclass to use for this action mapping object Defaults to the type specified by the enclosing <action-mappings> element or to orgapachestrutsactionActionMapping if not specified forward: Module-relative path of the servlet or other resource that processes this request, instead of the Action class specified by type You can specify one of the following: forward, include, or type include: Module-relative path of the servlet or other resource that processes this request, instead of the Action class specified by type You must specify one of the following: forward, include, or type