org.apache.struts2.interceptor.ServletConfigInterceptor Maven / Gradle / Ivy

/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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.interceptor;

import java.util.Map;

import javax.servlet.ServletContext;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.apache.struts2.StrutsStatics;
import org.apache.struts2.interceptor.servlet.ServletPrincipalProxy;
import org.apache.struts2.util.ServletContextAware;

import com.opensymphony.xwork2.ActionContext;
import com.opensymphony.xwork2.ActionInvocation;
import com.opensymphony.xwork2.interceptor.AbstractInterceptor;

/**
 * 
 * 
 * An interceptor which sets action properties based on the interfaces an action implements. For example, if the action
 * implements {@link ParameterAware} then the action context's parameter map will be set on it.
 * 
 *
 * This interceptor is designed to set all properties an action needs if it's aware of servlet parameters, the
 * servlet context, the session, etc. Interfaces that it supports are:
 * 
 *
 * 
 *
 * {@link ServletContextAware}
 *
 * {@link ServletRequestAware}
 *
 * {@link ServletResponseAware}
 *
 * {@link ParameterAware} - deprecated since 2.5.4, please use {@link HttpParametersAware}
 *
 * {@link HttpParametersAware}
 *
 * {@link RequestAware}
 *
 * {@link SessionAware}
 *
 * {@link ApplicationAware}
 *
 * {@link PrincipalAware}
 *
 * 
 *
 * 
 *
 * Interceptor parameters:
 *
 * 
 *
 * 
 *
 * None
 *
 * 
 *
 * 
 *
 * Extending the interceptor:
 *
 * 
 *
 * There are no known extension points for this interceptor.
 *
 * 
 *
 * Example code:
 *
 *  * 
 * <action name="someAction" class="com.examples.SomeAction">
 *     <interceptor-ref name="servletConfig"/>
 *     <interceptor-ref name="basicStack"/>
 *     <result name="success">good_result.ftl</result>
 * </action>
 * 
 * 
 *
 * @see ServletContextAware
 * @see ServletRequestAware
 * @see ServletResponseAware
 * @see ParameterAware
 * @see HttpParametersAware
 * @see SessionAware
 * @see ApplicationAware
 * @see PrincipalAware
 */
public class ServletConfigInterceptor extends AbstractInterceptor implements StrutsStatics {

    private static final long serialVersionUID = 605261777858676638L;

    /**
     * Sets action properties based on the interfaces an action implements. Things like application properties,
     * parameters, session attributes, etc are set based on the implementing interface.
     *
     * @param invocation an encapsulation of the action execution state.
     * @throws Exception if an error occurs when setting action properties.
     */
    public String intercept(ActionInvocation invocation) throws Exception {
        final Object action = invocation.getAction();
        final ActionContext context = invocation.getInvocationContext();

        if (action instanceof ServletRequestAware) {
            HttpServletRequest request = (HttpServletRequest) context.get(HTTP_REQUEST);
            ((ServletRequestAware) action).setServletRequest(request);
        }

        if (action instanceof ServletResponseAware) {
            HttpServletResponse response = (HttpServletResponse) context.get(HTTP_RESPONSE);
            ((ServletResponseAware) action).setServletResponse(response);
        }

        if (action instanceof ParameterAware) {
            context.getParameters().applyParameters((ParameterAware) action);
        }

        if (action instanceof HttpParametersAware) {
            ((HttpParametersAware) action).setParameters(context.getParameters());
        }

        if (action instanceof ApplicationAware) {
            ((ApplicationAware) action).setApplication(context.getApplication());
        }
        
        if (action instanceof SessionAware) {
            ((SessionAware) action).setSession(context.getSession());
        }
        
        if (action instanceof RequestAware) {
            ((RequestAware) action).setRequest((Map) context.get("request"));
        }

        if (action instanceof PrincipalAware) {
            HttpServletRequest request = (HttpServletRequest) context.get(HTTP_REQUEST);
            if(request != null) {
                // We are in servtlet environment, so principal information resides in HttpServletRequest
                ((PrincipalAware) action).setPrincipalProxy(new ServletPrincipalProxy(request));
            }
        }
        if (action instanceof ServletContextAware) {
            ServletContext servletContext = (ServletContext) context.get(SERVLET_CONTEXT);
            ((ServletContextAware) action).setServletContext(servletContext);
        }
        return invocation.invoke();
    }
}