org.apache.struts2.result

Class StrutsResultSupport

java.lang.Object

org.apache.struts2.result.StrutsResultSupport

All Implemented Interfaces:

Result, Serializable, StrutsStatics

Direct Known Subclasses:

FreemarkerResult, PlainTextResult, PostbackResult, ServletDispatcherResult, ServletRedirectResult, StreamResult

public abstract class StrutsResultSupport
extends Object
implements Result, StrutsStatics

A base class for all Struts action execution results. The "location" param is the default parameter, meaning the most common usage of this result would be:

This class provides two common parameters for any subclass:

• location - the location to go to after execution (could be a jsp page or another action). It can be parsed as per the rules definied in the translateVariables method
• parse - true by default. If set to false, the location param will not be parsed for expressions
• encode - false by default. If set to false, the location param will not be url encoded. This only have effect when parse is true

NOTE: The encode param will only have effect when parse is true

In the struts.xml configuration file, these would be included as:

  <result name="success" type="redirect">
      <param name="location">foo.jsp</param>
  </result>

or

  <result name="success" type="redirect" >
      <param name="location">foo.jsp?url=${myUrl}</param>
      <param name="parse">true</param>
      <param name="encode">true</param>
  </result>
 

In the above case, myUrl will be parsed against Ognl Value Stack and then URL encoded.1

or when using the default parameter feature

  <result name="success" type="redirect">foo.jsp</result>
 

You should subclass this class if you're interested in adding more parameters or functionality to your Result. If you do subclass this class you will need to override doExecute(String, ActionInvocation).

Any custom result can be defined in struts.xml as:

  <result-types>
      ...
      <result-type name="myresult" class="com.foo.MyResult" />
  </result-types>
 

Please see the Result class for more info on Results in general.

See Also:

Result, Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
static String	DEFAULT_PARAM The default parameter
static String	DEFAULT_URL_ENCODING use UTF-8 as this is the recommended encoding by W3C to avoid incompatibilities.
protected boolean	parseLocation

Fields inherited from interface org.apache.struts2.StrutsStatics

HTTP_REQUEST, HTTP_RESPONSE, PAGE_CONTEXT, SERVLET_CONTEXT, SERVLET_DISPATCHER, STRUTS_ACTION_TAG_INVOCATION, STRUTS_PORTLET_CONTEXT

Constructor Summary

Constructors

Constructor and Description
StrutsResultSupport()
StrutsResultSupport(String location)
StrutsResultSupport(String location, boolean parse, boolean encode)

Method Summary

Modifier and Type	Method and Description
protected String	conditionalParse(String param, ActionInvocation invocation) Parses the parameter for OGNL expressions against the valuestack
protected Collection<String>	conditionalParseCollection(String param, ActionInvocation invocation, boolean excludeEmptyElements) As conditionalParse(String, ActionInvocation) but does not convert found object into String.
protected abstract void	doExecute(String finalLocation, ActionInvocation invocation) Executes the result given a final location (jsp page, action, etc) and the action invocation (the state in which the action was executed).
void	execute(ActionInvocation invocation) Implementation of the execute method from the Result interface.
String	getLastFinalLocation() Returns the last parsed and encoded location value
String	getLocation() Gets the location it was created with, mainly for testing
void	setEncode(boolean encode) Set encode to true to indicate that the location should be url encoded.
void	setLocation(String location) The location to go to after action execution.
void	setParse(boolean parse) Set parse to true to indicate that the location should be parsed as an OGNL expression.

Methods inherited from class java.lang.Object

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

Field Detail

DEFAULT_PARAM

public static final String DEFAULT_PARAM

The default parameter

See Also:

Constant Field Values

DEFAULT_URL_ENCODING

public static final String DEFAULT_URL_ENCODING

use UTF-8 as this is the recommended encoding by W3C to avoid incompatibilities.

See Also:

Constant Field Values

parseLocation

protected boolean parseLocation

Constructor Detail

StrutsResultSupport

public StrutsResultSupport()

StrutsResultSupport

public StrutsResultSupport(String location)

StrutsResultSupport

public StrutsResultSupport(String location,
                           boolean parse,
                           boolean encode)

Method Detail

setLocation

public void setLocation(String location)

The location to go to after action execution. This could be a JSP page or another action. The location can contain OGNL expressions which will be evaulated if the parse parameter is set to true.

Parameters:

location - the location to go to after action execution.

See Also:

setParse(boolean)

getLocation

public String getLocation()

Gets the location it was created with, mainly for testing

Returns:

the location

getLastFinalLocation

public String getLastFinalLocation()

Returns the last parsed and encoded location value

Returns:

the last final location

setParse

public void setParse(boolean parse)

Set parse to true to indicate that the location should be parsed as an OGNL expression. This is set to true by default.

Parameters:

parse - true if the location parameter is an OGNL expression, false otherwise.

setEncode

public void setEncode(boolean encode)

Set encode to true to indicate that the location should be url encoded. This is set to true by default

Parameters:

encode - true if the location parameter should be url encode, false otherwise.

execute

public void execute(ActionInvocation invocation)
             throws Exception

Implementation of the execute method from the Result interface. This will call the abstract method doExecute(String, ActionInvocation) after optionally evaluating the location as an OGNL evaluation.

Specified by:

execute in interface Result

Parameters:

invocation - the execution state of the action.

Throws:

Exception - if an error occurs while executing the result.

conditionalParse

protected String conditionalParse(String param,
                                  ActionInvocation invocation)

Parses the parameter for OGNL expressions against the valuestack

Parameters:

param - The parameter value

invocation - The action invocation instance

Returns:

the resulting string

conditionalParseCollection

protected Collection<String> conditionalParseCollection(String param,
                                                        ActionInvocation invocation,
                                                        boolean excludeEmptyElements)

As conditionalParse(String, ActionInvocation) but does not convert found object into String. If found object is a collection it is returned if found object is not a collection it is wrapped in one.

Parameters:

param - parameter

invocation - action invocation

excludeEmptyElements - 'true' for excluding empty elements

Returns:

the parsed collection of strings

doExecute

protected abstract void doExecute(String finalLocation,
                                  ActionInvocation invocation)
                           throws Exception

Executes the result given a final location (jsp page, action, etc) and the action invocation (the state in which the action was executed). Subclasses must implement this class to handle custom logic for result handling.

Parameters:

finalLocation - the location (jsp page, action, etc) to go to.

invocation - the execution state of the action.

Throws:

Exception - if an error occurs while executing the result.