org.pentaho.platform.web.servlet.JAXRSServlet.java Source code

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Here is the source code for org.pentaho.platform.web.servlet.JAXRSServlet.java

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/*!
 * This program is free software; you can redistribute it and/or modify it under the
 * terms of the GNU Lesser General Public License, version 2.1 as published by the Free Software
 * Foundation.
 *
 * You should have received a copy of the GNU Lesser General Public License along with this
 * program; if not, you can obtain a copy at http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html
 * or from the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
 * without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 * See the GNU Lesser General Public License for more details.
 *
 * Copyright (c) 2002-2013 Pentaho Corporation..  All rights reserved.
 */

package org.pentaho.platform.web.servlet;

import com.sun.jersey.api.core.ResourceConfig;
import com.sun.jersey.spi.container.WebApplication;
import com.sun.jersey.spi.spring.container.servlet.SpringServlet;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.pentaho.platform.engine.core.system.PentahoSystem;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ConfigurableApplicationContext;
import org.springframework.core.io.FileSystemResource;
import org.springframework.core.io.Resource;
import org.springframework.web.context.ConfigurableWebApplicationContext;
import org.springframework.web.context.support.XmlWebApplicationContext;

import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.ws.rs.core.MediaType;
import javax.ws.rs.ext.MessageBodyWriter;
import java.io.File;
import java.io.IOException;
import java.lang.reflect.InvocationHandler;
import java.lang.reflect.Method;
import java.lang.reflect.Proxy;
import java.util.Enumeration;
import java.util.List;
import java.util.Map;

/**
 * This should only be used by a plugin in the plugin.spring.xml file to initialize a Jersey. The presence of this
 * servlet in the spring file will make it possible to write JAX-RS POJOs in your plugin.
 * 
 * @author Aaron Phillips
 */
public class JAXRSServlet extends SpringServlet {

    private static final long serialVersionUID = 457538570048660945L;

    private static final Log logger = LogFactory.getLog(JAXRSServlet.class);
    public static final String MIME_TYPE = "mime-type";
    public static final String GET_HEADERS = "getHeaders";
    public static final String ACCEPT = "accept";
    public static final String GET = "GET";

    @Override
    protected ConfigurableApplicationContext getContext() {
        return (ConfigurableApplicationContext) getAppContext();
    }

    @Override
    public void service(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {

        if (logger.isDebugEnabled()) {
            logger.debug("servicing request for resource " + request.getPathInfo()); //$NON-NLS-1$
        }

        if (request.getMethod().equals(GET)) {
            // Extension to allow accept type override from mime-type query param
            final String mimeType = request.getParameter(MIME_TYPE);
            if (mimeType != null) {
                final HttpServletRequest originalRequest = request;

                request = (HttpServletRequest) Proxy.newProxyInstance(getClass().getClassLoader(),
                        new Class[] { HttpServletRequest.class }, new InvocationHandler() {
                            public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
                                if (method.getName().equals(GET_HEADERS) && args.length > 0
                                        && args[0].equals(ACCEPT)) {
                                    return new Enumeration() {
                                        boolean hasMore = true;

                                        @Override
                                        public boolean hasMoreElements() {
                                            return hasMore;
                                        }

                                        @Override
                                        public Object nextElement() {
                                            hasMore = false;
                                            return mimeType;
                                        }
                                    };
                                }
                                return method.invoke(originalRequest, args);
                            }
                        });
            }
        }
        super.service(request, response);
    }

    @Override
    public void service(ServletRequest req, ServletResponse res) throws ServletException, IOException {
        super.service(req, res);
    }

    @SuppressWarnings("unchecked")
    @Override
    protected void initiate(ResourceConfig rc, WebApplication wa) {
        if (logger.isDebugEnabled()) {
            rc.getFeatures().put(ResourceConfig.FEATURE_TRACE, true);
            rc.getFeatures().put(ResourceConfig.FEATURE_TRACE_PER_REQUEST, true);
        }
        super.initiate(rc, wa);
        if (logger.isDebugEnabled()) {
            Map<MediaType, List<MessageBodyWriter>> writers = wa.getMessageBodyWorkers()
                    .getWriters(MediaType.WILDCARD_TYPE);
            logger.debug("Writers: " + writers); //$NON-NLS-1$
        }
    }

    protected ApplicationContext getAppContext() {

        ConfigurableWebApplicationContext wac = new XmlWebApplicationContext() {
            @Override
            protected Resource getResourceByPath(String path) {
                return new FileSystemResource(new File(path));
            }
        };

        wac.setServletContext(getServletContext());
        wac.setServletConfig(getServletConfig());
        wac.setNamespace(getServletName());
        String springFile = PentahoSystem.getApplicationContext()
                .getSolutionPath("system" + File.separator + "pentahoServices.spring.xml"); //$NON-NLS-1$ //$NON-NLS-2$
        wac.setConfigLocations(new String[] { springFile });
        wac.refresh();

        return wac;
    }

}