httpframe.java

很棒的web服务器源代码

		    }
		    return COND_OK;
		}
	    }
	} else if (fresource != null) {
	    long cmt = getLastModified();
	    if ( ims >= 0 ) {
		if (cmt > 0) {
		    long s_cmt = cmt / 1000;
		    long s_ims = ims / 1000;		    
		    if (s_cmt < s_ims) {
			return COND_FAILED;
		    } else if (s_cmt == s_ims) {
			return COND_WEAK;
		    }
		    return COND_OK;
		}
	    }
	}
	return 0;
    }

    /**
     * Check the <code>If-Unmodified-Since</code> condition of that request.
     * @param request The request to check.
     * @return An integer, either <code>COND_FAILED</cond> if condition
     * was checked, but failed, <code>COND_OK</code> if condition was checked
     * and succeeded, or <strong>0</strong> if the condition was not checked
     * at all (eg because the resource or the request didn't support it).
     */

    public int checkIfUnmodifiedSince(Request request) {
	if (fresource != null) {
	    // Check for an If-Unmodified-Since conditional:
	    long iums = request.getIfUnmodifiedSince();
	    long cmt = getLastModified();
	    if ( iums >= 0 ) 
		return ((cmt > 0) && (cmt - 1000) >= iums) 
		    ? COND_FAILED : COND_OK;
	}
	return 0;
    }

    /**
     * Check the <code>Expect</code> condition of that request
     * @param request The request to check.
     * @return A boolean <code>true</code> if the requirement is known
     */

    public boolean checkExpect(Request request) {
	// crude for now as we only support 100-continue
	// so FIXME for a more evolved version of this.
	String exp = request.getExpect();
	if (exp != null) {
	    if (!exp.equalsIgnoreCase(HTTP.HTTP_100_CONTINUE)) {
		return false;
	    }
	}
	return true;
    }

    /**
     * check the validators namely LMT/Etags according to rfc2616 rules
     * @return An integer, either <code>COND_FAILED</cond> if condition
     * was checked, but failed, <code>COND_OK</code> if condition was checked
     * and succeeded, or <strong>0</strong> if the condition was not checked
     * at all (eg because the resource or the request didn't support it).
     */
    public int checkValidators(Request request) {
	int v_inm = checkIfNoneMatch(request);
	int v_ims = checkIfModifiedSince(request);

	if ((v_inm == COND_OK) || (v_ims == COND_OK)) {
	    return COND_OK;
	}
	if ((v_inm == COND_FAILED) || (v_ims == COND_FAILED)) {
	    return COND_FAILED;
	}
	if ((v_inm == COND_WEAK) || (v_ims == COND_WEAK)) {
	    return COND_FAILED;
	}
	return 0;
    }

     /**
     * Lookup the target resource. Lookup filters and then resource.
     * @param ls The current lookup state
     * @param lr The result
     * @return true if lookup is done.
     * @exception ProtocolException If an error relative to the protocol occurs
     * @see org.w3c.tools.resources.ResourceFrame#lookupFilters
     * @see #lookupResource
     */
    public boolean lookup(LookupState ls, LookupResult lr) 
	throws ProtocolException
    {
	RequestInterface req = ls.getRequest(); 
	if (! checkRequest(req)) 
	    return false;
	if (lookupFilters(ls,lr))
	    return true;
	return lookupResource(ls,lr);
    }

     /**
     * Lookup the target resource (dispath to more specific lookup methods).
     * @param ls The current lookup state
     * @param lr The result
     * @return true if lookup is done.
     * @exception ProtocolException If an error relative to the protocol occurs
     * @see #lookupDirectory
     * @see #lookupFile
     * @see #lookupOther
     */
    protected boolean lookupResource(LookupState ls, LookupResult lr) 
	throws ProtocolException
    {
	if (fresource != null) {
	    return lookupFile(ls,lr);
	} else if (dresource != null) {
	    return lookupDirectory(ls,lr);
	} else {
	    return lookupOther(ls,lr);
	}
    }

    /**
     * Lookup the target resource when associated with a DirectoryResource.
     * @param ls The current lookup state
     * @param lr The result
     * @return true if lookup is done.
     * @exception ProtocolException If an error relative to the protocol
     * occurs
     */
    protected boolean lookupDirectory(LookupState ls, LookupResult lr) 
	throws ProtocolException
    {
	// Give a chance to our super-class to run its own lookup scheme:
	// do we have to create a resource (PUT) ?
	if ((ls.hasMoreComponents()) && getPutableFlag()) {
	    Request request = (Request) ls.getRequest() ;
	    if ((request == null) || request.getMethod().equals("PUT")) {
		// We might well want to create a resource:
		String            name = ls.peekNextComponent() ;
		ResourceReference rr   = dresource.lookup(name);
		if ((rr == null) && (dresource.getExtensibleFlag())) {
		    if (ls.countRemainingComponents() == 1)
			rr = dresource.createResource(name, request);
		    else
			rr = dresource.createDirectoryResource(name);
		    if (rr == null) {
			Reply error = 
			    request.makeReply(HTTP.UNSUPPORTED_MEDIA_TYPE);
			error.setContent(
			    "Failed to create resource "+
			    name +" : "+
			    "Unable to create the appropriate file:"+
			    request.getURLPath()+
			    " this media type is not supported");
			throw new HTTPException (error);
		    }
		} else if (rr == null) {
		    Reply error = request.makeReply(HTTP.FORBIDDEN) ;
		    error.setContent("You are not allowed to create resource "+
				     name +" : "+
				     dresource.getIdentifier()+
				     " is not extensible.");
		    throw new HTTPException (error);
		}
	    }
	}
	if ( super.lookup(ls, lr) ) {
	    if ( ! ls.isDirectory() && ! ls.isInternal() ) {
		// The directory lookup URL doesn't end with a slash:
		Request request = (Request)ls.getRequest() ;
		if ( request == null ) {
		    lr.setTarget(null);
		    return true;
		}
		URL url = null;
		try {
		    if ((request != null ) && 
			request.hasState(Request.ORIG_URL_STATE)) {
			URL oldurl;
			oldurl = (URL)request.getState(Request.ORIG_URL_STATE);
			url = new URL(oldurl, oldurl.getFile() + "/");
		    } else {
			url = (ls.hasRequest() 
			       ? getURL(request)
			       : new URL(getServer().getURL(), 
					 resource.getURLPath()));
		    }
		} catch (MalformedURLException ex) {
		    getServer().errlog(this, "unable to build full URL.");
		    throw new HTTPException("Internal server error");
		}
		String msg = "Invalid requested URL: the directory resource "+
		    " you are trying to reach is available only through "+
		    " its full URL: <a href=\""+
		    url + "\">" + url + "</a>.";
		if ( getRelocateFlag() ) {
		    // Emit an error (with reloc if allowed)
		    Reply reloc = request.makeReply(HTTP.FOUND);
		    reloc.setContent(msg) ;
		    reloc.setLocation(url);
		    lr.setTarget(null);
		    lr.setReply(reloc);
		    return true;
		} else {
		    Reply error = request.makeReply(HTTP.NOT_FOUND) ;
		    error.setContent(msg) ;
		    lr.setTarget(null);
		    lr.setReply(error);
		    return true;
		}
	    } else if ( ! ls.isInternal() ) {
		Request request = (Request)ls.getRequest() ;
		request.setState(STATE_CONTENT_LOCATION, "true");
		// return the index file.
		String indexes[] = getIndexes();
		if (indexes != null) {
		    for (int i = 0 ; i < indexes.length ; i++) {
			String index = indexes[i];
			if ( index != null && index.length() > 0) {
			    DirectoryResource dir = 
				(DirectoryResource) resource;
			    ResourceReference rr = dir.lookup(index);
			    if (rr != null) {
				try {
				    FramedResource rindex = 
					(FramedResource) rr.lock();
				    return rindex.lookup(ls,lr);
				} catch (InvalidResourceException ex) {
				} finally {
				    rr.unlock();
				}
			    }
			}
		    }	
		}
	    }
	    return true;
	}
	return false;
    }

    /**
     * Lookup the target resource when associated with a FileResource.
     * @param ls The current lookup state
     * @param lr The result
     * @return true if lookup is done.
     * @exception ProtocolException If an error relative to the protocol occurs
     */
    protected boolean lookupFile(LookupState ls, LookupResult lr) 
	throws ProtocolException
    {
	return super.lookup(ls,lr);
    }

    /**
     * Lookup the target resource when associated with an unknown resource.
     * @param ls The current lookup state
     * @param lr The result
     * @return true if lookup is done.
     * @exception ProtocolException If an error relative to the protocol occurs
     */
    protected boolean lookupOther(LookupState ls, LookupResult lr) 
	throws ProtocolException
    {
	return super.lookup(ls,lr);
    }

    /**
     * Check the request.
     * @param request the incomming request.
     * @return true if the request is an HTTP Request. 
     */
    public boolean checkRequest(RequestInterface request) {
	return ((request == null) 
		? true 
		:(request instanceof org.w3c.jigsaw.http.Request));
    }

    /**
     * Perform the request on all the frames of that resource. The
     * Reply returned is the first non-null reply.
     * @param request A RequestInterface instance.
     * @return A ReplyInterface instance.
     * @exception ProtocolException If an error relative to the protocol occurs
     * @exception ResourceException If an error not relative to the 
     * protocol occurs
     */
    protected ReplyInterface performFrames(RequestInterface request) 
	throws ProtocolException, ResourceException
    {
	return super.performFrames(request);
    }

    /**
     * Perform the request
     * @param req The request to handle.
     * @exception ProtocolException If processsing the request failed.
     * @exception ResourceException If the resource got a fatal error.
     */

    public ReplyInterface perform(RequestInterface req) 
	throws ProtocolException, ResourceException
    {
	ReplyInterface repi = super.perform(req);
	if (repi != null)
	    return repi;

	if (! checkRequest(req))
	    return null;

	Reply  reply  = null;
	Request request = (Request) req;
	String method = request.getMethod () ;
	// Perform the request:
	if ( method.equals("GET") ) {
	    reply = get(request) ;
	} else if ( method.equals("HEAD") ) {
	    reply = head(request) ;
	} else if ( method.equals("POST") ) {
	    reply = post(request) ;
	} else if ( method.equals("PUT") ) {
	    reply = put(request) ;
	} else if ( method.equals("OPTIONS") ) {
	    reply = options(request);
	} else if ( method.equals("DELETE") ) {
	    reply = delete(request) ;
	} else if ( method.equals("LINK") ) {
	    reply = link(request) ;
	} else if ( method.equals("UNLINK") ) {
	    reply = unlink(request) ;
	} else if ( method.equals("TRACE") ) {
	    reply = trace(request) ;
	} else {
	    reply = extended(request) ;
	}
	return reply;
    }

    /**
     * The default GET method.
     * @param request The request to handle.
     * @exception ProtocolException If processsing the request failed.
     * @exception ResourceException If the resource got a fatal error.
     */

    public Reply get(Request request)
	throws ProtocolException, ResourceException
    {
	if (dresource != null) {
	    // we manage a DirectoryResource
	    return getDirectoryResource(request) ;
	} else if (fresource != null) {
	    // we manage a FileResource
	    return getFileResource(request);
	} else {
	    return getOtherResource(request);
	}
    }

    /**
     * The default GET method for other king of associated resource
     * @param request The request to handle.
     * @exception ProtocolException If processsing the request failed.
     * @exception ResourceException If the resource got a fatal error.
     */
    protected Reply getOtherResource(Request request) 
	throws ProtocolException, ResourceException
    {
	if (resource instanceof ContainerResource) {
	    return getDirectoryResource(request);
	} else {
	    // we don't manage this kind of resource
	    Reply error = request.makeReply(HTTP.NOT_IMPLEMENTED) ;
	    error.setContent("Method GET not implemented.") ;
	    throw new HTTPException (error) ;
	}
    }

    /**
     * Create the reply relative to the given file.
     * @param request the incomming request.
     * @return A Reply instance
     * @exception ProtocolException If processsing the request failed.
     * @exception ResourceException If the resource got a fatal error.
     */
    protected Reply createFileReply(Request request) 
	throws ProtocolException, ResourceException
    {
	File file = fresource.getFile() ;
	Reply reply = null;
	// Check for a range request:
	HttpRange ranges[] = request.getRange();
	if ((ranges != null) && (ranges.length == 1)) {
	    Reply rangereply = handleRangeRequest(request, ranges[0]);
	    if ( rangereply != null )
		return rangereply;
	}
	// Default to full reply:
	reply = createDefaultReply(request, HTTP.OK) ;
	try { 
	    reply.setStream(new FileInputStream(file));
	} catch (IOException ex) {
	    Reply error = request.makeReply(HTTP.SERVICE_UNAVAILABLE);
	    error.setContent("Error while accessing filesystem");
	    return error;
	}
	return reply ;
    }

    /**
     * Alway throws an HTTPException
     */
    protected Reply deleteMe(Request request) 
	throws HTTPException
    {
	// Delete the resource if parent is extensible:
	boolean shrinkable = false;
	ResourceReference rr = fresource.getParent();
	ResourceReference rrtemp = null;
	Resource p = null;
	while ( true ) {
	    try {
		if (rr == null)
		    break;