package uk.org.woodcraft.bookings.interceptors;
/*
* 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.
*/
import java.util.Collection;
import java.util.List;
import java.util.Map;
import org.apache.struts2.dispatcher.ServletActionRedirectResult;
import org.apache.struts2.dispatcher.ServletRedirectResult;
import com.opensymphony.xwork2.ActionInvocation;
import com.opensymphony.xwork2.Result;
import com.opensymphony.xwork2.ValidationAware;
import com.opensymphony.xwork2.interceptor.MethodFilterInterceptor;
/**
* An Interceptor to preserve an actions ValidationAware messages across a
* redirect result.
*
* It makes the assumption that you always want to preserve messages across a
* redirect and restore them to the next action if they exist.
*
* The way this works is it looks at the result type after a action has executed
* and if the result was a redirect (ServletRedirectResult) or a redirectAction
* (ServletActionRedirectResult) and there were any errors, messages, or
* fieldErrors they are stored in the session. Before the next action executes
* it will check if there are any messages stored in the session and add them to
* the next action.
*
*/
public class RedirectMessageInterceptor extends MethodFilterInterceptor
{
private static final long serialVersionUID = -1847557437429753540L;
public static final String FIELD_ERRORS_KEY = "RedirectMessageInterceptor_FieldErrors";
public static final String ACTION_ERRORS_KEY = "RedirectMessageInterceptor_ActionErrors";
public static final String ACTION_MESSAGES_KEY = "RedirectMessageInterceptor_ActionMessages";
public RedirectMessageInterceptor()
{
}
public String doIntercept(ActionInvocation invocation) throws Exception
{
Object action = invocation.getAction();
if (action instanceof ValidationAware)
{
before(invocation, (ValidationAware) action);
}
String result = invocation.invoke();
if (action instanceof ValidationAware)
{
after(invocation, (ValidationAware) action);
}
return result;
}
/**
* Retrieve the errors and messages from the session and add them to the
* action.
*/
protected void before(ActionInvocation invocation,
ValidationAware validationAware)
throws Exception
{
Map<String, ?> session = invocation.getInvocationContext().getSession();
@SuppressWarnings({ "unchecked", "rawtypes" })
Collection<String> actionErrors = (Collection) session.remove(ACTION_ERRORS_KEY);
if (actionErrors != null && actionErrors.size() > 0)
{
for (String error : actionErrors)
{
validationAware.addActionError(error);
}
}
@SuppressWarnings({ "unchecked", "rawtypes" })
Collection<String> actionMessages = (Collection) session.remove(ACTION_MESSAGES_KEY);
if (actionMessages != null && actionMessages.size() > 0)
{
for (String message : actionMessages)
{
validationAware.addActionMessage(message);
}
}
@SuppressWarnings({ "unchecked", "rawtypes" })
Map<String, List<String>> fieldErrors = (Map) session.remove(FIELD_ERRORS_KEY);
if (fieldErrors != null && fieldErrors.size() > 0)
{
for (Map.Entry<String, List<String>> fieldError : fieldErrors.entrySet())
{
for (String message : fieldError.getValue())
{
validationAware.addFieldError(fieldError.getKey(), message);
}
}
}
}
/**
* If the result is a redirect then store error and messages in the session.
*/
protected void after(ActionInvocation invocation,
ValidationAware validationAware)
throws Exception
{
Result result = invocation.getResult();
if (result != null
&& (result instanceof ServletRedirectResult ||
result instanceof ServletActionRedirectResult))
{
Map<String, Object> session = invocation.getInvocationContext().getSession();
Collection<String> actionErrors = validationAware.getActionErrors();
if (actionErrors != null && actionErrors.size() > 0)
{
session.put(ACTION_ERRORS_KEY, actionErrors);
}
Collection<String> actionMessages = validationAware.getActionMessages();
if (actionMessages != null && actionMessages.size() > 0)
{
session.put(ACTION_MESSAGES_KEY, actionMessages);
}
Map<String, List<String>> fieldErrors = validationAware.getFieldErrors();
if (fieldErrors != null && fieldErrors.size() > 0)
{
session.put(FIELD_ERRORS_KEY, fieldErrors);
}
}
}
}