// FileServlet - servlet similar to a standard httpd//// Copyright (C)1996,1998 by Jef Poskanzer <jef@acme.com>. All rights reserved.//// Redistribution and use in source and binary forms, with or without// modification, are permitted provided that the following conditions// are met:// 1. Redistributions of source code must retain the above copyright//    notice, this list of conditions and the following disclaimer.// 2. Redistributions in binary form must reproduce the above copyright//    notice, this list of conditions and the following disclaimer in the//    documentation and/or other materials provided with the distribution.//// THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND// ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE// ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE// FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL// DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS// OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)// HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT// LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY// OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF// SUCH DAMAGE.//// Visit the ACME Labs Java page for up-to-date versions of this and other// fine Java utilities: http://www.acme.com/java/// // All enhancments Copyright (C)1998,2000 by Dmitriy Rogatkin// http://tjws.sourceforge.netpackage Acme.Serve;import java.io.*;import java.util.*;import java.text.*;import javax.servlet.*;import javax.servlet.http.*;/// Servlet similar to a standard httpd.// <P>// Implements the "GET" and "HEAD" methods for files and directories.// Handles index.html, index.htm, default.htm, default.html.// Redirects directory URLs that lack a trailing /.// Handles If-Modified-Since.// <P>// <A HREF="/resources/classes/Acme/Serve/FileServlet.java">Fetch the software.</A><BR>// <A HREF="/resources/classes/Acme.tar.Z">Fetch the entire Acme package.</A>// <P>// @see Acme.Serve.Serve// All enhancments Copyright (C)1998-2000 by Dmitriy Rogatkin// this version is compatible with the latest JSDK 2.2// http://tjws.sourceforge.netpublic class FileServlet extends HttpServlet {    // We keep a single throttle table for all instances of the servlet.    // Normally there is only one instance; the exception is subclasses.    static Acme.WildcardDictionary throttleTab = null;    static final String[] DEFAULTINDEXPAGES = {"index.html", "index.htm", "default.htm", "default.html"};    static final DecimalFormat lengthftm = new DecimalFormat("#");	private static final boolean logenabled =//		true;		false;    /// Constructor.    public FileServlet()    {    }    /// Constructor with throttling.    // @param throttles filename containing throttle settings    // @see ThrottledOutputStream    public FileServlet( String throttles ) throws IOException    {        this();        readThrottles( throttles );    }    private void readThrottles( String throttles ) throws IOException    {        Acme.WildcardDictionary newThrottleTab =        ThrottledOutputStream.parseThrottleFile( throttles );        if ( throttleTab == null )            throttleTab = newThrottleTab;        else {            // Merge the new one into the old one.            Enumeration keys = newThrottleTab.keys();            Enumeration elements = newThrottleTab.elements();            while ( keys.hasMoreElements() ) {                Object key = keys.nextElement();                Object element = elements.nextElement();                throttleTab.put( key, element );            }        }    }    /// Returns a string containing information about the author, version, and    // copyright of the servlet.    public String getServletInfo()    {        return "servlet similar to a standard httpd";    }    /// Services a single request from the client.    // @param req the servlet request    // @param req the servlet response    // @exception ServletException when an exception has occurred    public void service( HttpServletRequest req, HttpServletResponse res ) throws ServletException, IOException    {        boolean headOnly;        if ( req.getMethod().equalsIgnoreCase( "get" ) )            headOnly = false;        else if ( ! req.getMethod().equalsIgnoreCase( "head" ) )            headOnly = true;        else {            res.sendError( HttpServletResponse.SC_NOT_IMPLEMENTED );            return;        }		String path = req.getPathInfo();		if (path != null && path.length() > 2) {			path = path.replace( '\\', '/');			if ( path.indexOf( "/../" ) >0 || path.endsWith( "/.." ) ) {				res.sendError( HttpServletResponse.SC_FORBIDDEN );				return;			}		}        dispatchPathname( req, res, headOnly, path );    }    private void dispatchPathname( HttpServletRequest req, HttpServletResponse res, boolean headOnly, String path ) throws IOException    {		String filename = req.getPathTranslated()!=null?req.getPathTranslated().replace( '/', File.separatorChar ):"";        if ( filename.length() > 0 && filename.charAt( filename.length() - 1 ) == File.separatorChar )            filename = filename.substring( 0, filename.length() - 1 );        File file = new File( filename );		log("showing "+filename+" for path "+path);        if ( file.exists() ) {            if ( ! file.isDirectory() )                serveFile( req, res, headOnly, path, file );			else {				log("showing dir "+file);				if ( path.charAt( path.length() - 1 ) != '/' )					redirectDirectory( req, res, path, file );				else 										showIdexFile(req, res, headOnly, path, filename);			}		} else {			for (int i=0; i<DEFAULTINDEXPAGES.length; i++) {				if ( filename.endsWith( File.separator+DEFAULTINDEXPAGES[i] ) ) {					showIdexFile(req, res, headOnly, path, file.getParent());					return;				}			}			res.sendError( HttpServletResponse.SC_NOT_FOUND );		}	}	private void showIdexFile(HttpServletRequest req, HttpServletResponse res,							  boolean headOnly, String path, String parent) throws IOException {		log("showing index in directory "+parent);		for (int i=0; i<DEFAULTINDEXPAGES.length; i++) {			File indexFile = new File( parent, DEFAULTINDEXPAGES[i] );			if ( indexFile.exists() ) {				serveFile(req, res, headOnly, path, indexFile );				return;			}		}		// index not found		serveDirectory(req, res, headOnly, path, new File(parent) );	}	    private void serveFile( HttpServletRequest req, HttpServletResponse res, boolean headOnly, String path, File file ) throws IOException    {        log( "getting " + file );        if ( ! file.canRead() ) {            res.sendError( HttpServletResponse.SC_FORBIDDEN );            return;        }        // Handle If-Modified-Since.        res.setStatus( HttpServletResponse.SC_OK );        long lastMod = file.lastModified();        String ifModSinceStr = req.getHeader( "If-Modified-Since" );        long ifModSince = -1;        if ( ifModSinceStr != null ) {            int semi = ifModSinceStr.indexOf( ';' );            if ( semi != -1 )                ifModSinceStr = ifModSinceStr.substring( 0, semi );            try {                ifModSince =                DateFormat.getDateInstance().parse( ifModSinceStr ).getTime();            } catch ( Exception ignore ) {            }        }        if ( ifModSince != -1 && ifModSince == lastMod ) {            res.setStatus( HttpServletResponse.SC_NOT_MODIFIED );            headOnly = true;        }        res.setContentType( getServletContext().getMimeType( file.getName() ) );        res.setContentLength( (int) file.length() );        res.setDateHeader( "Last-modified", lastMod );        OutputStream out = res.getOutputStream();        if ( ! headOnly ) {            // Check throttle.            if ( throttleTab != null ) {                ThrottleItem throttleItem =                (ThrottleItem) throttleTab.get( path );                if ( throttleItem != null ) {                    // !!! Need to account for multiple simultaneous fetches.                    out = new ThrottledOutputStream(                                                   out, throttleItem.getMaxBps() );                }            }            InputStream in = new FileInputStream( file );            copyStream( in, out );            in.close();        }        out.close();    }    /// Copy a file from in to out.    // Sub-classes can override this in order to do filtering of some sort.    public void copyStream( InputStream in, OutputStream out ) throws IOException    {        Acme.Utils.copyStream( in, out );    }    private void serveDirectory( HttpServletRequest req, HttpServletResponse res, boolean headOnly, String path, File file ) throws IOException    {        log( "indexing " + file );        if ( ! file.canRead() ) {            res.sendError( HttpServletResponse.SC_FORBIDDEN );            return;        }        res.setStatus( HttpServletResponse.SC_OK );        res.setContentType( "text/html" );        OutputStream out = res.getOutputStream();        if ( ! headOnly ) {            PrintStream p = new PrintStream( new BufferedOutputStream( out ) );            p.println( "<HTML><HEAD>" );            p.println( "<TITLE>Index of " + path + "</TITLE>" );            p.println( "</HEAD><BODY BGCOLOR=\"#F1D0F2\">" );            p.println( "<H2>Index of " + path + "</H2>" );            p.println( "<PRE>" );            p.println( "mode         bytes  last-changed  name" );            p.println( "<HR>" );            String[] names = file.list();            Acme.Utils.sortStrings( names );            for ( int i = 0; i < names.length; ++i ) {                File aFile = new File( file, names[i] );                String aFileType;                if ( aFile.isDirectory() )                    aFileType = "d";                else if ( aFile.isFile() )                    aFileType = "-";                else                    aFileType = "?";                String aFileRead = ( aFile.canRead() ? "r" : "-" );                String aFileWrite = ( aFile.canWrite() ? "w" : "-" );                String aFileExe = "-";                String aFileSize = lengthftm.format( aFile.length() );                while (aFileSize.length() < 12)                    aFileSize = " "+aFileSize;                String aFileDate =                Acme.Utils.lsDateStr( new Date( aFile.lastModified() ) );                while (aFileDate.length() < 14)                    aFileDate += " ";                String aFileDirsuf = ( aFile.isDirectory() ? "/" : "" );                String aFileSuf = ( aFile.isDirectory() ? "/" : "" );                p.println(                         aFileType + aFileRead + aFileWrite + aFileExe +                         "  " + aFileSize + "  " + aFileDate + "  " +                         "<A HREF=\"" + names[i] + aFileDirsuf + "\">" +                         names[i] + aFileSuf + "</A>" );            }            p.println( "</PRE>" );            p.println( "<HR>" );            Serve.Identification.writeAddress( p );            p.println( "</BODY></HTML>" );            p.flush();        }        out.close();    }    private void redirectDirectory( HttpServletRequest req, HttpServletResponse res, String path, File file ) throws IOException    {        log( "redirecting " + path );        res.sendRedirect( path + "/" );    }    public void log(String msg)    {        if (logenabled)            super.log(msg);    }}