org.springframework.webflow.executor.support
Class RequestPathFlowExecutorArgumentHandler

java.lang.Object
  org.springframework.webflow.executor.support.FlowExecutorArgumentHandler
      org.springframework.webflow.executor.support.RequestParameterFlowExecutorArgumentHandler
          org.springframework.webflow.executor.support.RequestPathFlowExecutorArgumentHandler

All Implemented Interfaces:

FlowExecutorArgumentExposer, FlowExecutorArgumentExtractor

public class RequestPathFlowExecutorArgumentHandler
extends RequestParameterFlowExecutorArgumentHandler

Flow executor argument handler that extracts arguments from the request path and exposes them in the URL path.

This allows for REST-style URLs to launch flows in the general format: http://${host}/${context path}/${dispatcher path}/${flowId}.

For example, the URL http://localhost/springair/reservation/booking would launch a new execution of the booking flow, assuming a context path of /springair and a servlet mapping of /reservation/*.

This also allows for URLs to resume flow executions in the format: http://${host}/${context path}/${dispatcher path}/${key delimiter}/${flowExecutionKey}.

For example, the URL http://localhost/springair/reservation/k/ABC123XYZ would resume flow execution "ABC123XYZ".

Note: this implementation only works with ExternalContext implementations that return valid ExternalContext.getRequestPathInfo() such as the ServletExternalContext. Furthermore, it assumes that the controller handling flow requests is not identified using request path information. For instance, mapping the dispatcher to "*.html" in web.xml would work since in this case the flow controller will be identified as part of the dispatcher name (e.g. "flows.html"). Mapping the dispatcher to "/html/*" in web.xml will not work since that would require the flow controller to be identified by the extra request path information (e.g. "/html/flows").

Author:

Keith Donald

Constructor Summary

RequestPathFlowExecutorArgumentHandler()

Method Summary

protected void	appendFlowExecutorPath(java.lang.StringBuffer url, ExternalContext context) Append the URL path to the flow executor capable of accepting new requests.
java.lang.String	createFlowDefinitionUrl(FlowDefinitionRedirect flowDefinitionRedirect, ExternalContext context) Create a URL that when redirected to launches a entirely new execution of a flow definition (starts a new conversation).
java.lang.String	createFlowExecutionUrl(java.lang.String flowExecutionKey, FlowExecutionContext flowExecution, ExternalContext context) Create a URL path that when redirected to renders the current (or last) view selection made by the flow execution identified by the flow execution key.
java.lang.String	extractFlowExecutionKey(ExternalContext context) Extract the flow execution key from the external context.
java.lang.String	extractFlowId(ExternalContext context) Extracts the flow id from the external context.
java.lang.String	getKeyDelimiter() Returns the key delimiter.
boolean	isFlowExecutionKeyPresent(ExternalContext context) Returns true if the flow execution key is extractable from the context.
boolean	isFlowIdPresent(ExternalContext context) Returns true if the flow id is extractable from the context.
void	setKeyDelimiter(java.lang.String keyDelimiter) Sets the delimiter that when present in the requestPathInfo indicates the flowExecutionKey follows in the URL.

Methods inherited from class org.springframework.webflow.executor.support.RequestParameterFlowExecutorArgumentHandler

appendQueryParameter, appendQueryParameters, createExternalUrl, extractEventId, findParameter, getParameterValueDelimiter, isEventIdPresent, setParameterValueDelimiter

Methods inherited from class org.springframework.webflow.executor.support.FlowExecutorArgumentHandler

applyDefaultFlowId, encodeValue, exposeFlowExecutionContext, getDefaultFlowId, getEventIdArgumentName, getFlowExecutionContextAttributeName, getFlowExecutionKeyArgumentName, getFlowExecutionKeyAttributeName, getFlowIdArgumentName, getUrlEncodingScheme, isRedirectContextRelative, makeRedirectUrlContextRelativeIfNecessary, setDefaultFlowId, setEventIdArgumentName, setFlowExecutionContextAttributeName, setFlowExecutionKeyArgumentName, setFlowExecutionKeyAttributeName, setFlowIdArgumentName, setRedirectContextRelative, setUrlEncodingScheme

Methods inherited from class java.lang.Object

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

Constructor Detail

RequestPathFlowExecutorArgumentHandler

public RequestPathFlowExecutorArgumentHandler()

Method Detail

getKeyDelimiter

public java.lang.String getKeyDelimiter()

Returns the key delimiter. Defaults to "k".

Returns:

the key delimiter

setKeyDelimiter

public void setKeyDelimiter(java.lang.String keyDelimiter)

Sets the delimiter that when present in the requestPathInfo indicates the flowExecutionKey follows in the URL. Defaults to "k".

Parameters:

keyDelimiter - the key delimiter

See Also:

extractFlowExecutionKey(ExternalContext)

isFlowIdPresent

public boolean isFlowIdPresent(ExternalContext context)

Description copied from interface: FlowExecutorArgumentExtractor

Returns true if the flow id is extractable from the context.

Specified by:

isFlowIdPresent in interface FlowExecutorArgumentExtractor

Overrides:

isFlowIdPresent in class RequestParameterFlowExecutorArgumentHandler

Parameters:

context - the context in which a external user event occured

Returns:

true if extractable, false if not

extractFlowId

public java.lang.String extractFlowId(ExternalContext context)

Description copied from interface: FlowExecutorArgumentExtractor

Extracts the flow id from the external context.

Specified by:

extractFlowId in interface FlowExecutorArgumentExtractor

Overrides:

extractFlowId in class RequestParameterFlowExecutorArgumentHandler

Parameters:

context - the context in which a external user event occured

Returns:

the extracted flow id

isFlowExecutionKeyPresent

public boolean isFlowExecutionKeyPresent(ExternalContext context)

Description copied from interface: FlowExecutorArgumentExtractor

Returns true if the flow execution key is extractable from the context.

Specified by:

isFlowExecutionKeyPresent in interface FlowExecutorArgumentExtractor

Overrides:

isFlowExecutionKeyPresent in class RequestParameterFlowExecutorArgumentHandler

Parameters:

context - the context in which a external user event occured

Returns:

true if extractable, false if not

extractFlowExecutionKey

public java.lang.String extractFlowExecutionKey(ExternalContext context)
                                         throws FlowExecutorArgumentExtractionException

Description copied from interface: FlowExecutorArgumentExtractor

Extract the flow execution key from the external context.

Specified by:

extractFlowExecutionKey in interface FlowExecutorArgumentExtractor

Overrides:

extractFlowExecutionKey in class RequestParameterFlowExecutorArgumentHandler

Parameters:

context - the context in which the external user event occured

Returns:

the obtained flow execution key

Throws:

FlowExecutorArgumentExtractionException - if the flow execution key could not be extracted

createFlowDefinitionUrl

public java.lang.String createFlowDefinitionUrl(FlowDefinitionRedirect flowDefinitionRedirect,
                                                ExternalContext context)

Description copied from interface: FlowExecutorArgumentExposer

Create a URL that when redirected to launches a entirely new execution of a flow definition (starts a new conversation). Used to support the restart flow and redirect to flow use cases.

Specified by:

createFlowDefinitionUrl in interface FlowExecutorArgumentExposer

Overrides:

createFlowDefinitionUrl in class RequestParameterFlowExecutorArgumentHandler

Parameters:

flowDefinitionRedirect - the flow definition redirect view selection

context - the external context

Returns:

the relative flow URL path to redirect to

createFlowExecutionUrl

public java.lang.String createFlowExecutionUrl(java.lang.String flowExecutionKey,
                                               FlowExecutionContext flowExecution,
                                               ExternalContext context)

Description copied from interface: FlowExecutorArgumentExposer

Create a URL path that when redirected to renders the current (or last) view selection made by the flow execution identified by the flow execution key. Used to support the flow execution redirect use case.

Specified by:

createFlowExecutionUrl in interface FlowExecutorArgumentExposer

Overrides:

createFlowExecutionUrl in class RequestParameterFlowExecutorArgumentHandler

Parameters:

flowExecutionKey - the flow execution key

flowExecution - the flow execution

context - the external context

Returns:

the relative conversation URL path

See Also:

FlowExecutionRedirect

appendFlowExecutorPath

protected void appendFlowExecutorPath(java.lang.StringBuffer url,
                                      ExternalContext context)

Description copied from class: RequestParameterFlowExecutorArgumentHandler

Append the URL path to the flow executor capable of accepting new requests.

Overrides:

appendFlowExecutorPath in class RequestParameterFlowExecutorArgumentHandler

Parameters:

url - the url buffer to append to

context - the context of this request