org.impalaframework.web.jsp.ModuleJspServlet Maven / Gradle / Ivy
/*
* Copyright 2007-2010 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.impalaframework.web.jsp;
import java.io.IOException;
import javax.servlet.ServletConfig;
import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.impalaframework.web.servlet.qualifier.WebAttributeQualifier;
/**
* Simple servlet implementation which is able to wrap a JSP invocation. Setup
* require and use requires the following:
*
* - Ensure that the property 'partitioned.servlet.context' is set to true in
* impala.properties
*
- Add a JSP servlet entry into the module itself, for example using an
* entry such as the following:
* <bean id="jspServlet" class="org.impalaframework.web.jsp.JspServletFactoryBean">
<property name="servletName" value="jspServlet"/>
</bean>
*
* Note that direct external invocation to JSPs hosted within modules via this
* servlet is not supported. Invocation is expected to be internally within the
* application, for example via {@link java.servet.RequestDispatcher}
* forward() or include() calls.
*
* @author Phil Zoio
*/
public class ModuleJspServlet extends HttpServlet {
private static final long serialVersionUID = 1L;
private ServletContext servletContext;
@Override
public void init(ServletConfig config) throws ServletException {
super.init(config);
this.servletContext = config.getServletContext();
}
@Override
protected void service(HttpServletRequest req, HttpServletResponse resp)
throws ServletException, IOException {
final String prefix = (String) req.getAttribute(WebAttributeQualifier.MODULE_QUALIFIER_PREFIX);
if (prefix == null) {
throw new IllegalStateException("Cannot resolve attribute '" + WebAttributeQualifier.MODULE_QUALIFIER_PREFIX + "'." +
" This attribute needs to be set in order for ModuleJspServlet to be able to find the module registered JSP servlet to which the request will be forwarded." +
" Possible causes: 1) you have not set the property 'partitioned.servlet.context=true' in impala.properties, or " +
" 2) you have attempted to access the JSP directly rather than through a request or forward from a servlet or filter within the application.");
}
final HttpServlet jspServlet = (HttpServlet) servletContext.getAttribute(prefix + JspConstants.JSP_SERVLET);
if (jspServlet == null) {
throw new IllegalStateException("No JSP servlet registered in the module to which the request was directed." +
" Your module configuration requires a " + JspServletFactoryBean.class + " configuration entry, or equivalent.");
}
jspServlet.service(req, resp);
}
@Override
protected void doGet(HttpServletRequest req, HttpServletResponse resp)
throws ServletException, IOException {
service(req, resp);
}
@Override
protected void doPost(HttpServletRequest req, HttpServletResponse resp)
throws ServletException, IOException {
service(req, resp);
}
}