/*
* $Id: ActionComponent.java 451544 2006-09-30 05:38:02Z mrdon $
*
* Copyright 2006 The Apache Software Foundation.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.struts2.components;
import java.io.IOException;
import java.io.Writer;
import java.util.HashMap;
import java.util.Map;
import javax.servlet.ServletContext;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.jsp.PageContext;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.struts2.ServletActionContext;
import org.apache.struts2.StrutsException;
import org.apache.struts2.dispatcher.Dispatcher;
import org.apache.struts2.dispatcher.RequestMap;
import org.apache.struts2.views.jsp.TagUtils;
import com.opensymphony.xwork2.ActionContext;
import com.opensymphony.xwork2.ActionProxy;
import com.opensymphony.xwork2.ActionProxyFactory;
import com.opensymphony.xwork2.config.Configuration;
import com.opensymphony.xwork2.util.ValueStack;
import com.opensymphony.xwork2.util.ValueStackFactory;
/**
* <!-- START SNIPPET: javadoc -->
* <p>This tag enables developers to call actions directly from a JSP page by specifying the action name and an optional
* namespace. The body content of the tag is used to render the results from the Action. Any result processor defined
* for this action in struts.xml will be ignored, <i>unless</i> the executeResult parameter is specified.</p>
* <!-- END SNIPPET: javadoc -->
*
* <!-- START SNIPPET: params -->
* <ul>
* <li>id (String) - the id (if specified) to put the action under stack's context.
* <li>name* (String) - name of the action to be executed (without the extension suffix eg. .action)</li>
* <li>namespace (String) - default to the namespace where this action tag is invoked</li>
* <li>executeResult (Boolean) - default is false. Decides wheather the result of this action is to be executed or not</li>
* <li>ignoreContextParams (Boolean) - default to false. Decides wheather the request parameters are to be included when the action is invoked</li>
* </ul>
* <!-- END SNIPPET: params -->
*
* <pre>
* <!-- START SNIPPET: javacode -->
* public class ActionTagAction extends ActionSupport {
*
* public String execute() throws Exception {
* return "done";
* }
*
* public String doDefault() throws Exception {
* ServletActionContext.getRequest().setAttribute("stringByAction", "This is a String put in by the action's doDefault()");
* return "done";
* }
* }
* <!-- END SNIPPET: javacode -->
* </pre>
*
* <pre>
* <!-- START SNIPPET: strutsxml -->
* <xwork>
* ....
* <action name="actionTagAction1" class="tmjee.testing.ActionTagAction">
* <result name="done">success.jsp</result>
* </action>
* <action name="actionTagAction2" class="tmjee.testing.ActionTagAction" method="default">
* <result name="done">success.jsp</result>
* </action>
* ....
* </xwork>
* <!-- END SNIPPET: strutsxml -->
* </pre>
*
* <pre>
* <!-- START SNIPPET: example -->
* <div>The following action tag will execute result and include it in this page</div>
* <br />
* <s:action name="actionTagAction" executeResult="true" />
* <br />
* <div>The following action tag will do the same as above, but invokes method specialMethod in action</div>
* <br />
* <s:action name="actionTagAction!specialMethod" executeResult="true" />
* <br />
* <div>The following action tag will not execute result, but put a String in request scope
* under an id "stringByAction" which will be retrieved using property tag</div>
* <s:action name="actionTagAction!default" executeResult="false" />
* <s:property value="#attr.stringByAction" />
* <!-- END SNIPPET: example -->
* </pre>
*
* @s.tag name="action" tld-body-content="JSP" tld-tag-class="org.apache.struts2.views.jsp.ActionTag"
* description="Execute an action from within a view"
*/
public class ActionComponent extends Component {
private static final Log LOG = LogFactory.getLog(ActionComponent.class);
protected HttpServletResponse res;
protected HttpServletRequest req;
protected ActionProxy proxy;
protected String name;
protected String namespace;
protected boolean executeResult;
protected boolean ignoreContextParams;
public ActionComponent(ValueStack stack, HttpServletRequest req, HttpServletResponse res) {
super(stack);
this.req = req;
this.res = res;
}
public boolean end(Writer writer, String body) {
boolean end = super.end(writer, "", false);
try {
try {
writer.flush();
} catch (IOException e) {
LOG.warn("error while trying to flush writer ", e);
}
executeAction();
if ((getId() != null) && (proxy != null)) {
getStack().setValue("#attr['" + getId() + "']",
proxy.getAction());
}
} finally {
popComponentStack();
}
return end;
}
private Map createExtraContext() {
Map parentParams = null;
if (!ignoreContextParams) {
parentParams = new ActionContext(getStack().getContext()).getParameters();
}
Map newParams = (parentParams != null) ? new HashMap(parentParams) : new HashMap();
if (parameters != null) {
newParams.putAll(parameters);
}
ActionContext ctx = new ActionContext(stack.getContext());
ServletContext servletContext = (ServletContext) ctx.get(ServletActionContext.SERVLET_CONTEXT);
PageContext pageContext = (PageContext) ctx.get(ServletActionContext.PAGE_CONTEXT);
Map session = ctx.getSession();
Map application = ctx.getApplication();
Dispatcher du = Dispatcher.getInstance();
Map extraContext = du.createContextMap(new RequestMap(req),
newParams,
session,
application,
req,
res,
servletContext);
ValueStack newStack = ValueStackFactory.getFactory().createValueStack(stack);
extraContext.put(ActionContext.VALUE_STACK, newStack);
// add page context, such that ServletDispatcherResult will do an include
extraContext.put(ServletActionContext.PAGE_CONTEXT, pageContext);
return extraContext;
}
public ActionProxy getProxy() {
return proxy;
}
/**
* Execute the requested action. If no namespace is provided, we'll
* attempt to derive a namespace using buildNamespace(). The ActionProxy
* and the namespace will be saved into the instance variables proxy and
* namespace respectively.
*
* @see org.apache.struts2.views.jsp.TagUtils#buildNamespace
*/
private void executeAction() {
String actualName = findString(name, "name", "Action name is required. Example: updatePerson");
if (actualName == null) {
throw new StrutsException("Unable to find value for name " + name);
}
// handle "name!method" convention.
final String actionName;
final String methodName;
int exclamation = actualName.lastIndexOf("!");
if (exclamation != -1) {
actionName = actualName.substring(0, exclamation);
methodName = actualName.substring(exclamation + 1);
} else {
actionName = actualName;
methodName = null;
}
String namespace;
if (this.namespace == null) {
namespace = TagUtils.buildNamespace(getStack(), req);
} else {
namespace = findString(this.namespace);
}
// get the old value stack from the request
ValueStack stack = getStack();
// execute at this point, after params have been set
try {
Configuration config = Dispatcher.getInstance().getConfigurationManager().getConfiguration();
proxy = ActionProxyFactory.getFactory().createActionProxy(config, namespace, actionName, createExtraContext(), executeResult, true);
if (null != methodName) {
proxy.setMethod(methodName);
}
// set the new stack into the request for the taglib to use
req.setAttribute(ServletActionContext.STRUTS_VALUESTACK_KEY, proxy.getInvocation().getStack());
proxy.execute();
} catch (Exception e) {
String message = "Could not execute action: " + namespace + "/" + actualName;
LOG.error(message, e);
} finally {
// set the old stack back on the request
req.setAttribute(ServletActionContext.STRUTS_VALUESTACK_KEY, stack);
}
if ((getId() != null) && (proxy != null)) {
final Map context = stack.getContext();
context.put(getId(), proxy.getAction());
}
}
/**
* the id (if speficied) to put the action under stack's context.
* @s.tagattribute required="false" type="String"
*/
public void setId(String id) {
super.setId(id);
}
/**
* name of the action to be executed (without the extension suffix eg. .action)
* @s.tagattribute required="true" type="String"
*/
public void setName(String name) {
this.name = name;
}
/**
* namespace for action to call
* @s.tagattribute required="false" type="String" default="namespace from where tag is used"
*/
public void setNamespace(String namespace) {
this.namespace = namespace;
}
/**
* whether the result of this action (probably a view) should be executed/rendered
* @s.tagattribute required="false" type="Boolean" default="false"
*/
public void setExecuteResult(boolean executeResult) {
this.executeResult = executeResult;
}
/**
* whether the request parameters are to be included when the action is invoked
* @s.tagattribute required="false" type="Boolean" default="false"
*/
public void setIgnoreContextParams(boolean ignoreContextParams) {
this.ignoreContextParams = ignoreContextParams;
}
}