oracle.dss.thin.servlet
Class ServletRequestHandler

java.lang.Object
  |
  +--oracle.dss.thin.servlet.ServletRequestHandler

public class ServletRequestHandler

extends java.lang.Object

ServletRequestHandler is an implementation of a simple servlet controller for ThinBeans. In order to use the ServletRequestHandler, an servlet would create a ServletRequestHandler and place it on its HttpSession. ThinBeans that exist across requests ( are stored in the HttpSession ) should also be registered with the ServletRequestHandler. When a request reaches the servlet, the servlet should make sure that all of the ThinBeans that are needed for the request have been created and registered with the ServletRequestHandler and then call the handleRequest() method on its ServletRequestHandler, which will perform the following tasks on the ThinBeans registered with the ServletRequestHandler:

• set the state of all registered ThinBeans
• find the ThinBean that should handle the event and call its event handler

If an application needs to set state and process events at different times an application can call setState() and handleEvent(), which is equivalent to calling handleRequest(). If an application wants to customize state or event handling, they can either implement their own controller or they can subclass the ServletRequestHandler and implement their own setState(), handleEvent(), and getState() methods.

If the servlet wants to place the state of the registered ThinBeans onto subsequent events then it needs to call getStateStrings() add the list of state strings as hidden form fields on the HTML form that contains the ThinBean.

Constructor Summary

ServletRequestHandler()
Default Constructor

Method Summary

java.util.Locale	getLocale() Retrieves the Locale that the ThinBeanUIs uses.
java.util.Dictionary	getState(oracle.cabo.share.url.URLEncoder encoder) Retrieves a dictionary of state strings, which can be placed onto URLs for subsequent events by adding hidden forms to the form(s) that contain ThinBeans.
ThinBean	getThinBean(java.lang.String thinBeanName) Returns a registered ThinBean by name
java.util.Enumeration	getThinBeanNames() Retrieves an Enumeration of the names, as Strings, of ThinBeans registered with this instance of the ServletRequestHandler.
int	handleEvent(QueryParameterProvider provider) Routes the current event to the correct ThinBean.
int	handleRequest(QueryParameterProvider provider) Handles the request by setting state on registered ThinBeans and then routing the current event to the correct ThinBean.
int	handleRequest(QueryParameterProvider provider, oracle.cabo.servlet.state.State[] states) Handles the request by setting state on registered ThinBeans and then routing the current event to the correct ThinBean.
void	registerThinBean(ThinBean bean) Registers a ThinBean with the RequestHandler.
void	registerThinBean(ThinBeanUI bean) Registers a ThinBeanUI with the RequestHandler.
void	setLocale(java.util.Locale locale) Specifies the Locale for all of the ThinBeanUIs.
void	setState(QueryParameterProvider provider) Sets state on registered ThinBeans
void	setState(oracle.cabo.servlet.state.State state) Sets state on registered ThinBeans that is stored in a oracle.cabo.servlet.state.State object instead of on the URL.
boolean	unregisterThinBean(ThinBean bean) Unregisters a ThinBean with the RequestHandler.

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

ServletRequestHandler

public ServletRequestHandler()

Default Constructor

Method Detail

handleRequest

public int handleRequest(QueryParameterProvider provider)
                  throws ThinException

Handles the request by setting state on registered ThinBeans and then routing the current event to the correct ThinBean. This is the equivalent of calling setState(provider) and then handleEvent(). NOTE : This method should only be called if all of the ThinBean state is on the URL. If the state is split between the URL and session variables, such as a StateManager, then handleRequest(provider, states) should be called.

Parameters:

provider - the QueryParameterProvider for the current request

Returns:

the status of the request processing, which is either ThinBeanUI.EVENT_NOT_HANDLED, ThinBeanUI.EVENT_HANDLED, or ThinBeanUI.EVENT_REQUEST_DONE

handleRequest

public int handleRequest(QueryParameterProvider provider,
                         oracle.cabo.servlet.state.State[] states)
                  throws ThinException

Handles the request by setting state on registered ThinBeans and then routing the current event to the correct ThinBean. This is the equivalent of calling setState(provider), setState(state) for every State object, and then handleEvent().

Parameters:

provider - the QueryParameterProvider for the current request

states - an array of State objects that contain ThinBean state.

Returns:

the status of the request processing, which is either ThinBeanUI.EVENT_NOT_HANDLED, ThinBeanUI.EVENT_HANDLED, or ThinBeanUI.EVENT_REQUEST_DONE

setState

public void setState(QueryParameterProvider provider)
              throws ThinException

Sets state on registered ThinBeans

Parameters:

provider - the QueryParameterProvider for the current request

setState

public void setState(oracle.cabo.servlet.state.State state)
              throws ThinException

Sets state on registered ThinBeans that is stored in a oracle.cabo.servlet.state.State object instead of on the URL. ThinBean state can be placed into a state object and the state object's id should be placed onto the URL. The state is fetched from its oracle.cabo.servlet.state.StateManager by id. This method assumes that the names of the state properties coorespond to the names of registered ThinBeans.

If ThinBean state is contained by in the URL and in the State object, then this method should be called in addition to setState(QueryParameterProvider).

If an application has stored ThinBean state in multiple State object, then this method can be called multiple times.

Parameters:

state - a State instance

Throws:

ThinException -

handleEvent

public int handleEvent(QueryParameterProvider provider)
                throws ThinException

Routes the current event to the correct ThinBean.

Parameters:

provider - the QueryParameterProvider for the current request

Returns:

the status of the request processing, which is either ThinBeanUI.EVENT_NOT_HANDLED, ThinBeanUI.EVENT_HANDLED, or ThinBeanUI.EVENT_REQUEST_DONE

getState

public java.util.Dictionary getState(oracle.cabo.share.url.URLEncoder encoder)

Retrieves a dictionary of state strings, which can be placed onto URLs for subsequent events by adding hidden forms to the form(s) that contain ThinBeans.

Parameters:

encoder - the URLEncoder to use when determining parameter names

Returns:

a dictionary of state strings

setLocale

public void setLocale(java.util.Locale locale)

Specifies the Locale for all of the ThinBeanUIs.

Parameters:

locale - The Locale for this ThinBeanUI.

getLocale

public java.util.Locale getLocale()

Retrieves the Locale that the ThinBeanUIs uses.

Returns:

The Locale for the ThinBeanUIs.

registerThinBean

public void registerThinBean(ThinBean bean)

Registers a ThinBean with the RequestHandler.

Parameters:

bean - the ThinBean being registered.

registerThinBean

public void registerThinBean(ThinBeanUI bean)

Registers a ThinBeanUI with the RequestHandler.

Parameters:

bean - the ThinBeanUI being registered.

unregisterThinBean

public boolean unregisterThinBean(ThinBean bean)

Unregisters a ThinBean with the RequestHandler.

Parameters:

bean - the ThinBean being unregistered.

getThinBean

public ThinBean getThinBean(java.lang.String thinBeanName)

Returns a registered ThinBean by name

Parameters:

thinBeanName - the name of the registered ThinBean

Returns:

the registered ThinBean, or null if it is not present

getThinBeanNames

public java.util.Enumeration getThinBeanNames()

Retrieves an Enumeration of the names, as Strings, of ThinBeans registered with this instance of the ServletRequestHandler.

Returns:

an Enumeration of ThinBean names.