de.highbyte_le.weberknecht.ControllerFilter.java Source code

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Here is the source code for de.highbyte_le.weberknecht.ControllerFilter.java

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/*
 * ControllerFilter.java
 *
 * Copyright 2013 Patrick Mairif.
 * The program is distributed under the terms of the Apache License (ALv2).
 * 
 * tabstop=4, charset=UTF-8
 */
package de.highbyte_le.weberknecht;

import java.io.IOException;
import java.sql.SQLException;

import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

import de.highbyte_le.weberknecht.conf.ConfigurationException;
import de.highbyte_le.weberknecht.conf.WeberknechtConf;
import de.highbyte_le.weberknecht.db.DbConnectionHolder;
import de.highbyte_le.weberknecht.db.DbConnectionProvider;
import de.highbyte_le.weberknecht.request.routing.Router;
import de.highbyte_le.weberknecht.request.routing.RoutingTarget;

/**
 * webapp controller using servlet filter mechanism
 * 
 * @author pmairif
 */
@SuppressWarnings({ "nls" })
public class ControllerFilter implements Filter {

    private ControllerCore core;

    /**
     * Logger for this class
     */
    private final Log log = LogFactory.getLog(ControllerFilter.class);

    /**
     * filter initialization
     */
    @Override
    public void init(FilterConfig filterConfig) throws ServletException {
        try {
            core = new ControllerCore(filterConfig.getServletContext());
        } catch (Exception e) {
            log.error("init() - Exception: " + e.getMessage(), e);
            throw new ServletException("internal error", e);
        }
    }

    protected void init(ServletContext servletContext, WeberknechtConf conf,
            DbConnectionProvider dbConnectionProvider) throws ClassNotFoundException, ConfigurationException {
        core = new ControllerCore(servletContext, conf, dbConnectionProvider);
    }

    /* (non-Javadoc)
     * @see javax.servlet.Filter#doFilter(javax.servlet.ServletRequest, javax.servlet.ServletResponse, javax.servlet.FilterChain)
     */
    @Override
    public void doFilter(ServletRequest request, ServletResponse response, FilterChain filterChain)
            throws IOException, ServletException {
        if (log.isDebugEnabled())
            log.debug("doFilter() - start");

        long start = System.currentTimeMillis();

        if (!(request instanceof HttpServletRequest) || !(response instanceof HttpServletResponse))
            throw new IllegalArgumentException("no http request");

        HttpServletRequest httpRequest = (HttpServletRequest) request;
        HttpServletResponse httpResponse = (HttpServletResponse) response;

        DbConnectionHolder conHolder = new DbConnectionHolder(core.getDbConnectionProvider());
        try {
            Router router = core.createRouter(conHolder); //choose router depending on config
            RoutingTarget routingTarget = router.routeUri(httpRequest);
            if (null == routingTarget) {
                filterChain.doFilter(request, response);
            } else {
                core.executeAction(httpRequest, httpResponse, conHolder, routingTarget);

                long finish = System.currentTimeMillis();
                if (log.isInfoEnabled()) {
                    log.info("service() - page delivery of '" + httpRequest.getRequestURI() + "' took "
                            + (finish - start) + " ms");
                }
            }
        } catch (Exception e1) {
            try {
                log.error("service() - exception while error handler instantiation: " + e1.getMessage(), e1); //$NON-NLS-1$

                //exceptions occurring here were not processed by weberknecht error handlers.
                //so it is probably a good idea to go on with the error handling of the container. 
                httpResponse.sendError(HttpServletResponse.SC_INTERNAL_SERVER_ERROR); //call error page 500
            } catch (IOException e) {
                log.error("service() - IOException: " + e.getMessage(), e); //$NON-NLS-1$
                httpResponse.setStatus(HttpServletResponse.SC_INTERNAL_SERVER_ERROR); //just return 500
            }
        } finally {
            try {
                conHolder.close();
            } catch (SQLException e) {
                log.error("service() - SQLException while closing db connection: " + e.getMessage()); //$NON-NLS-1$
            }
        }
    }

    /* (non-Javadoc)
     * @see javax.servlet.Filter#destroy()
     */
    @Override
    public void destroy() {
        //
    }
}