This document discusses the features and restrictions of the
This server was written with two things in mind:
- Compliance with the specifications, and
- Efficiency: High speed & Low memory usage
Every design decision in this project considered these two points.
Below are listed the notable features and
minor restrictions of this server.
There are a number of features that serparate this server from the pack.
- Conditionally HTTP/1.1 compilant.
- Servlet 2.2 compilant (minus some minor things specified in
- Persistent connections.
- Understands the "Chunked" transfer-coding.
- Basic authentication.
- Multiline headers.
- Support for nonstandard HTTP methods.
- URL rewriting for sessions.
- Quoted cookie values.
- Authenticated GET and POST servlets do not require any change to the
code other than changing the superclass from
- Remote server shutdown.
- Pays attention to
- The author's goal is compilance with the specifications.
This server was designed explicitly for an embedded Java platform.
Hence, there are a few minor limitations that must be considered and
accounted for in your designs.
aJile Version Limitations
java.io.BufferedReader classes are unsupported, so
any methods in the servlet API that use them are removed.
Specifically, the request and response objects are affected.
There is a class called
in the Tynamo™ core library that you can use for reading data
line by line. There is a
readLine() method that returns
null when there are no more lines to be read. This is a
InputStream object, with a constructor that takes
InputStream as an argument.
- Floating point to string conversion is not perfected yet, and may
display long repeating decimals. e.g. "0.09999999" instead of "0.1".
- The current version of the aJile firmware (3.16.09) uses the maximum
TCP timeout, and so sockets can be unavailable for two full minutes.
This was circumvented by using the
system property. It is set to 10 seconds (specified in ms), but can
be changed. This may be fixed in a future release of their software.
Servlet 2.2 Restrictions
- Response buffer size of 0. This means that simply retrieving an
output stream or writer will commit the response.
- No relative URLs permitted in
- The response is not "closed" after
RequestDispatcher.forward, or when the amount of
content specified in the "Content-Length" header has been written to
Except for the case of exceeding the specified content length,
there are no checks performed that catch a servlet writing out
content after these events.
- No JSP.
- Currently only one
ServletContext for all requested paths.
- Must add cookies and sessions before the response is committed.
- Does not pay attention to the time indicated by
A "Retry-After" header is sent during when servicing, but the container
does not wait to recreate the servlet for another request during
javax.servlet.context.tempdir context attribute is
method is called on a servlet immediately after a permanent
UnavailableException is detected. This means that the
servlet author should take care to properly synchronize and manage any
resources used during the
- There is a similar note for when the server is shut down. The
destroy method is called immediately, and any threads
running in the
service method are not given a chance to
complete. In other words, the server defined time limit is
- Changes from the Servlet/2.2 API:
- Not included:
javax.servlet.GenericServlet does not implement
javax.servlet.http.HttpServlet does not implement
javax.servlet.http.Cookie does not implement
- Because the firmware (3.16.09) does not support reflection,
javax.servlet.http.HttpServlet cannot determine
which methods to put into the "Allow" header when a "405
Method Not Allowed" error is sent.
- The "Expect" header is not supported.
- Path parameters are only allowed at the end of a path.
- Persistent connections are not used with the "chunked" transfer