Limitations.txt (DC, 01.25.01)

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TINI Firmware 1.02
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This file documents some of the current limitations of TINI.  This is not a
comprehensive list, but does contain most of the items of greatest interest.

Current Limitations
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- Loader
    Does not support baud rates below 19200.

- MulticastSocket
    Only 1 local interface can send and receive on a given group.

- TINI does not support IP datagram fragmentation/reassembly.

- java.net.Socket.setSoLinger is not implemented.

- TINI has 24 total allowed socket connections.

- TINI does not support IP layer routing.

- TINI currently supports only a subset of reflection. Class.forName(),
  newInstance(), etc. are supported, but java.lang.reflect.Array, Constructor,
  Field, etc. are not yet supported. See API_Diffs.txt for a full list of
  non-supported classes and methods.

- TINI does not currently support serialization.

- printStackTrace() is only partially supported. The fully qualified
  exception name will be printed, but not the method stack list. The full
  method names do not currently exist in the .tini files.

- Native modules can't be larger than 64k.

- The maximum size of any array is 64k.

- TINI OS limits the number of processes to 8, with 16 threads per Java
  process. One process is consumed by the sweeper. The application 
  (typically slush) is the 2nd OS process created and the 1st process
  running the JVM.

- There is a limitation of 64 stack cells for local variables. 32 bit
  bit variables (such as int, char, byte, etc) take up 1 stack cell. 64 bit
  variables (long, double) take 2.

- A class file is limited to 255 static fields (including all super classes'
  static fields) and 255 instance fields (including all super classes'
  instance fields).

- All threads run at the same priority. Thread.setPriority() will not throw
  an exception, but will not change the runtime priority of that thread.

- A class file is limited to 127 methods (including all super classes' methods,
  excluding native methods). A class file is limited to 255 native methods.

- A method is limited to 63 local variables.

- Only 2 ByteToChar (and CharToByte) are supported by default: UTF8, and
  ISO_8859_1. Others can be added by users in their Java programs.

- Only the default Locale is supported. Others can be added by users in their
  Java programs.

- Each converted class file can't be larger than 64k.

- PPP
    Dial on demand is not currently supported.  

    These methods are not currently supported:
      get/setIdleTimeout().

- 1-Wire
    2480 is not supported on ports other than serial1.

- String's intern() method returns incorrect results. A VM level hashtable
  has been added for String literals.

- TINI DHCP doesn't work with some DHCP servers. Known incompatibilies from
  the past: vDHCP, MagikDHCP, and Umax Ugate 3000 ADSL-sharing device.

- Directories can only hold 254 files. Attempting to add more will result in 
  an IOException.

- An IOException will be thrown when attempting to create files with names 
  longer than 247 characters.

- The last modified time for files may not be correct if the TINI is reset 
  during file system changes. The time reported could be the file's previous 
  last modified time.

- Cannot open a "rw" RandomAccessFile for a file that has been executed. An 
  IOException will be thrown from the constructor. This is also the case for a
  FileOutputStream with the append flag set to true.

- The method Date.toLocaleString() returns the same thing as
  Date.toString().  This is because TINI does not support any of the date
  formatting classes.

- Dates representing times before January 1, 1970 will not return correct
  values for their fields, either through a Calendar object or through a Date
  object.

- Properties.load() functions like JDK1.2 and not JDK1.1 with respect to
  keys and values that have spaces in them. For the line in a properties file:
              "a key =  a value"
  Disregarding the quotes, 1.1 returns key "a" and value "key =  a value".
  1.2 returns key "a key " and value "  a value".

- The methods Double.toString() and Double.valueOf(String) (and the associated 
  methods in the Float class) do not return correct values.  The formatting
  code and the String parsing code for floating point numbers is as accurate 
  as possible given limitations on API space and processor speed.  Floating 
  point numbers may often be printed slightly incorrectly as Strings.  For 
  instance, the code:
       System.out.println(3.05f);
  may produce the String "3.0499999".
  Note that floating point calculations are not affected by this statement, 
  only conversions from a String to a floating point number or from a 
  floating point number to a String.

-The static initializers for all classes will be run even if the class
 is never referenced.

-Classes that have circular references in the static initializers will
 not produce results that are consistent with the Java Language
 Specification.  The static initializers will be sorted as needed, but
 circular references cannot not be resolved and TINIConvertor will report
 an error with the offending classes.  The actual ordering of the
 initializers in the TINI executable in this situation will vary.


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