parametrizedfilter.java

CRM源码This file describes some issues that should be implemented in future and how it should be imple

/*
 * Copyright 2006-2007 Queplix Corp.
 *
 * Licensed under the Queplix Public License, Version 1.1.1 (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.queplix.com/solutions/commercial-open-source/queplix-public-license/
 *
 * 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 com.queplix.core.utils.www;

import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import java.io.IOException;
import java.util.Enumeration;
import java.util.HashMap;
import java.util.Map;

/**
 * <p>Basic filter, that reads configuration into array</p>
 * @author [DAG] Dmitry Gaponenko
 * @author [ALB] Baranov Andrey
 * @version $Revision: 1.1.1.1 $ $Date: 2005/09/12 15:31:24 $
 */

public abstract class ParametrizedFilter
    extends AbstractFilter {

    private Object[] params;
    private int paramsNum;

    /**
     * Initialize filter
     * @param filterConfig HTTP filter config
     * @throws ServletException
     */
    public void init( FilterConfig filterConfig )
        throws ServletException {

        HashMap paramsMap = new HashMap();
        for( Enumeration e = filterConfig.getInitParameterNames(); e.hasMoreElements(); ) {
            String name = ( String ) e.nextElement();
            String value = filterConfig.getInitParameter( name );
            paramsMap.put( name, value );
        }
        paramsNum = paramsMap.size();
        params = paramsMap.entrySet().toArray();
    }

    /**
     * Do filter
     * @param request HTTP request
     * @param response HTTP response
     * @param chain FilterChain object
     * @throws IOException
     * @throws ServletException
     */
    public void doFilter( ServletRequest request,
                          ServletResponse response,
                          FilterChain chain )
        throws IOException, ServletException {

        for( int j = 0; j < paramsNum; j++ ) {
            Map.Entry entry = ( Map.Entry ) params[j];
            String paramName = ( String ) entry.getKey();
            String paramValue = ( String ) entry.getValue();

            if( doFilterParam( request, response, chain, paramName, paramValue ) )
                return;
        }
        chain.doFilter( request, response );
    }

    /**
     * Destroy filter
     */
    public void destroy() {
        super.destroy();
        params = null;
    }

    /**
     * Abstract method wich performs filter params
     * @param request HTTP request
     * @param response HTTP response
     * @param chain FilterChain object
     * @param paramName param name
     * @param paramValue param value
     * @return <code>true</code> if procedure fail
     * @throws IOException
     * @throws ServletException
     */
    public abstract boolean doFilterParam( ServletRequest request,
                                           ServletResponse response,
                                           FilterChain chain,
                                           String paramName,
                                           String paramValue )
        throws IOException, ServletException;
}