Jetty example source code file (FilterHolder.java)

This example Jetty source code file (FilterHolder.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - Jetty tags/keywords

config, enumeration, exception, exception, filter, filter, filterconfig, filterholder, filterholder, holder, illegalstateexception, object, servlet, string, string, util

The Jetty FilterHolder.java source code

// ========================================================================
// Copyright 1996-2005 Mort Bay Consulting Pty. Ltd.
// ------------------------------------------------------------------------
// 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.mortbay.jetty.servlet;

import java.util.Enumeration;

import javax.servlet.Filter;
import javax.servlet.FilterConfig;
import javax.servlet.ServletContext;

import org.mortbay.jetty.Handler;
import org.mortbay.log.Log;

/* --------------------------------------------------------------------- */
/** 
 * @author Greg Wilkins
 */
public class FilterHolder
    extends Holder
{

    /* ------------------------------------------------------------ */
    /** Dispatch type from name
     */
    public static int dispatch(String type)
    {
        if ("request".equalsIgnoreCase(type))
            return Handler.REQUEST;
        if ("forward".equalsIgnoreCase(type))
            return Handler.FORWARD;
        if ("include".equalsIgnoreCase(type))
            return Handler.INCLUDE;
        if ("error".equalsIgnoreCase(type))
            return Handler.ERROR;
        throw new IllegalArgumentException(type);
    }
    
    /* ------------------------------------------------------------ */
    private transient Filter _filter;
    private transient Config _config;
        
    /* ---------------------------------------------------------------- */
    /** Constructor for Serialization.
     */
    public FilterHolder()
    {
    }   
    
    /* ---------------------------------------------------------------- */
    /** Constructor for Serialization.
     */
    public FilterHolder(Class filter)
    {
        super (filter);
    }

    /* ---------------------------------------------------------------- */
    /** Constructor for existing filter.
     */
    public FilterHolder(Filter filter)
    {
        setFilter(filter);
    }
    
    /* ------------------------------------------------------------ */
    public void doStart()
        throws Exception
    {
        super.doStart();
        
        if (!javax.servlet.Filter.class
            .isAssignableFrom(_class))
        {
            String msg = _class+" is not a javax.servlet.Filter";
            super.stop();
            throw new IllegalStateException(msg);
        }

        if (_filter==null)
            _filter=(Filter)newInstance();
        
        _filter = getServletHandler().customizeFilter(_filter);
        
        _config=new Config();
        _filter.init(_config);
    }

    /* ------------------------------------------------------------ */
    public void doStop()
    {      
        if (_filter!=null)
        {
            try
            {
                destroyInstance(_filter);
            }
            catch (Exception e)
            {
                Log.warn(e);
            }
        }
        if (!_extInstance)
            _filter=null;
        
        _config=null;
        super.doStop();   
    }
    
    public void destroyInstance (Object o)
    throws Exception
    {
        if (o==null)
            return;
        Filter f = (Filter)o;
        f.destroy();
        getServletHandler().customizeFilterDestroy(f);
    }

    /* ------------------------------------------------------------ */
    public synchronized void setFilter(Filter filter)
    {
        _filter=filter;
        _extInstance=true;
        setHeldClass(filter.getClass());
        if (getName()==null)
            setName(filter.getClass().getName());
    }
    
    /* ------------------------------------------------------------ */
    public Filter getFilter()
    {
        return _filter;
    }

    /* ------------------------------------------------------------ */
    public String toString()
    {
        return getName();
    }
    
    /* ------------------------------------------------------------ */
    /* ------------------------------------------------------------ */
    /* ------------------------------------------------------------ */
    class Config implements FilterConfig
    {
        /* ------------------------------------------------------------ */
        public String getFilterName()
        {
            return _name;
        }

        /* ------------------------------------------------------------ */
        public ServletContext getServletContext()
        {
            return _servletHandler.getServletContext();
        }
        
        /* -------------------------------------------------------- */
        public String getInitParameter(String param)
        {
            return FilterHolder.this.getInitParameter(param);
        }
    
        /* -------------------------------------------------------- */
        public Enumeration getInitParameterNames()
        {
            return FilterHolder.this.getInitParameterNames();
        }
    }
    


}