net.sf.farrago.server.FarragoServletCommandSink.java Source code

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Here is the source code for net.sf.farrago.server.FarragoServletCommandSink.java

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/*
// Licensed to DynamoBI Corporation (DynamoBI) under one
// or more contributor license agreements.  See the NOTICE file
// distributed with this work for additional information
// regarding copyright ownership.  DynamoBI 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 net.sf.farrago.server;

import java.io.*;
import java.sql.*;
import java.util.*;

import javax.servlet.*;
import javax.servlet.http.*;

import org.apache.commons.logging.*;

import de.simplicit.vjdbc.command.*;
import de.simplicit.vjdbc.serial.*;
import de.simplicit.vjdbc.server.command.*;
import de.simplicit.vjdbc.server.config.*;
import de.simplicit.vjdbc.servlet.*;
import de.simplicit.vjdbc.util.*;

/**
 * FarragoServletCommandSink was cloned from VJDBC ServletCommandSink.  We
 * could have foregone this entire class and simpy extended ServletCommandSink,
 * except _processor was private.  We just needed to add an additional member
 * (vjdbcConfig) and overload the init().
 *
 * @author ngoodman
 */
public class FarragoServletCommandSink extends HttpServlet {
    private static Log logger = LogFactory.getLog(FarragoServletCommandSink.class);

    private CommandProcessor processor;
    private VJdbcConfiguration vjdbcConfig;

    public FarragoServletCommandSink() {
    }

    public VJdbcConfiguration getVjdbcConfig() {
        return vjdbcConfig;
    }

    public void setVjdbcConfig(VJdbcConfiguration vjdbcConfig) {
        this.vjdbcConfig = vjdbcConfig;
    }

    public void init(ServletConfig servletConfig) throws ServletException {
        VJdbcConfiguration.init(vjdbcConfig);
        processor = CommandProcessor.getInstance();
    }

    public void destroy() {
    }

    protected void doGet(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse)
            throws ServletException {
        handleRequest(httpServletRequest, httpServletResponse);
    }

    protected void doPost(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse)
            throws ServletException {
        handleRequest(httpServletRequest, httpServletResponse);
    }

    private void handleRequest(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse)
            throws ServletException {
        ObjectInputStream ois = null;
        ObjectOutputStream oos = null;

        try {
            // Get the method to execute
            String method = httpServletRequest.getHeader(ServletCommandSinkIdentifier.METHOD_IDENTIFIER);

            if (method != null) {
                ois = new ObjectInputStream(httpServletRequest.getInputStream());
                // And initialize the output
                OutputStream os = httpServletResponse.getOutputStream();
                oos = new ObjectOutputStream(os);
                Object objectToReturn = null;

                try {
                    // Some command to process ?
                    if (method.equals(ServletCommandSinkIdentifier.PROCESS_COMMAND)) {
                        // Read parameter objects
                        Long connuid = (Long) ois.readObject();
                        Long uid = (Long) ois.readObject();
                        Command cmd = (Command) ois.readObject();
                        CallingContext ctx = (CallingContext) ois.readObject();
                        // Delegate execution to the CommandProcessor
                        objectToReturn = processor.process(connuid, uid, cmd, ctx);
                    } else if (method.equals(ServletCommandSinkIdentifier.CONNECT_COMMAND)) {
                        String url = ois.readUTF();
                        Properties props = (Properties) ois.readObject();
                        Properties clientInfo = (Properties) ois.readObject();
                        CallingContext ctx = (CallingContext) ois.readObject();

                        ConnectionConfiguration connectionConfiguration = VJdbcConfiguration.singleton()
                                .getConnection(url);

                        if (connectionConfiguration != null) {
                            Connection conn = connectionConfiguration.create(props);
                            objectToReturn = processor.registerConnection(conn, connectionConfiguration, clientInfo,
                                    ctx);
                        } else {
                            objectToReturn = new SQLException("VJDBC-Connection " + url + " not found");
                        }
                    }
                } catch (Throwable t) {
                    // Wrap any exception so that it can be transported back to
                    // the client
                    objectToReturn = SQLExceptionHelper.wrap(t);
                }

                // Write the result in the response buffer
                oos.writeObject(objectToReturn);
                oos.flush();

                httpServletResponse.flushBuffer();
            } else {
                // No VJDBC-Method ? Then we redirect the stupid browser user to
                // some information page :-)
                httpServletResponse.sendRedirect("index.html");
            }
        } catch (Exception e) {
            logger.error("Unexpected Exception", e);
            throw new ServletException(e);
        } finally {
            StreamCloser.close(ois);
            StreamCloser.close(oos);
        }
    }
}

// End FarragoServletCommandSink.java