/*
* Copyright 2004-2012 the original author or authors.
*
* 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.springframework.webflow.execution;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.core.style.ToStringCreator;
import org.springframework.util.Assert;
import org.springframework.util.StringUtils;
import org.springframework.webflow.core.AnnotatedObject;
/**
* An action proxy/decorator that stores arbitrary properties about a target <code>Action</code> implementation for use
* within a specific Action execution context, for example an <code>ActionState</code> definition, a
* <code>TransitionCriteria</code> definition, or in a test environment.
* <p>
* An annotated action is an action that wraps another action (referred to as the <i>target</i> action), setting up the
* target action's execution attributes before invoking {@link Action#execute}.
*
* @author Keith Donald
* @author Erwin Vervaet
*/
public class AnnotatedAction extends AnnotatedObject implements Action {
private static final Log logger = LogFactory.getLog(AnnotatedAction.class);
// well known attributes
/**
* The action name attribute ("name").
* <p>
* The name attribute is often used as a qualifier for an action's result event, and is typically used to allow the
* flow to respond to a specific action's outcome within a larger action execution chain.
*/
public static final String NAME_ATTRIBUTE = "name";
/**
* The action execution method attribute ("method").
* <p>
* The method property is a hint about what method should be invoked.
*/
public static final String METHOD_ATTRIBUTE = "method";
/**
* The target action to execute.
*/
private Action targetAction;
/**
* Creates a new annotated action object for the specified action. No contextual properties are provided.
* @param targetAction the action
*/
public AnnotatedAction(Action targetAction) {
setTargetAction(targetAction);
}
/**
* Returns the wrapped target action.
* @return the action
*/
public Action getTargetAction() {
return targetAction;
}
/**
* Set the target action wrapped by this decorator.
*/
public void setTargetAction(Action targetAction) {
Assert.notNull(targetAction, "The targetAction to annotate is required");
this.targetAction = targetAction;
}
/**
* Returns the name of a named action, or <code>null</code> if the action is unnamed. Used when mapping action
* result events to transitions.
* @see #isNamed()
* @see #postProcessResult(Event)
*/
public String getName() {
return getAttributes().getString(NAME_ATTRIBUTE);
}
/**
* Sets the name of a named action. This is optional and can be <code>null</code>.
* @param name the action name
*/
public void setName(String name) {
getAttributes().put(NAME_ATTRIBUTE, name);
}
/**
* Returns whether or not the wrapped target action is a named action.
* @see #getName()
* @see #setName(String)
*/
public boolean isNamed() {
return StringUtils.hasText(getName());
}
/**
* Returns the name of the action method to invoke when the target action is executed.
*/
public String getMethod() {
return getAttributes().getString(METHOD_ATTRIBUTE);
}
/**
* Sets the name of the action method to invoke when the target action is executed.
* @param method the action method name
*/
public void setMethod(String method) {
getAttributes().put(METHOD_ATTRIBUTE, method);
}
/**
* Set an attribute on this annotated object.
* @param attributeName the name of the attribute to set
* @param attributeValue the value of the attribute
* @return this object, to support call chaining
*/
public AnnotatedAction putAttribute(String attributeName, Object attributeValue) {
getAttributes().put(attributeName, attributeValue);
return this;
}
public Event execute(RequestContext context) throws Exception {
try {
if (logger.isDebugEnabled()) {
logger.debug("Putting action execution attributes " + getAttributes());
}
context.getAttributes().putAll(getAttributes());
Event result = getTargetAction().execute(context);
return postProcessResult(result);
} finally {
if (logger.isDebugEnabled()) {
logger.debug("Clearing action execution attributes " + getAttributes());
}
context.getAttributes().removeAll(getAttributes());
}
}
/**
* Get the event id to be used as grounds for a transition in the containing state, based on given result returned
* from action execution.
* <p>
* If the wrapped action is named, the name will be used as a qualifier for the event (e.g. "myAction.success").
* @param resultEvent the action result event
*/
protected Event postProcessResult(Event resultEvent) {
if (resultEvent == null) {
return null;
}
if (isNamed()) {
// qualify result event id with action name for a named action
String qualifiedId = getName() + "." + resultEvent.getId();
if (logger.isDebugEnabled()) {
logger.debug("Qualifying action result '" + resultEvent.getId() + "'; qualified result = '"
+ qualifiedId + "'");
}
resultEvent = new Event(resultEvent.getSource(), qualifiedId, resultEvent.getAttributes());
}
return resultEvent;
}
public String toString() {
return new ToStringCreator(this).append("targetAction", getTargetAction())
.append("attributes", getAttributes()).toString();
}
}