JamVM

File Release Notes and Changelog

Release Name: JamVM 1.4.3

Notes:
JamVM 1.4.3 is a major release.  The release number will be updated to
1.5.0 when all VM-level changes for 1.5.0 is complete. 

Changes:
A summary of changes since 1.4.2:

- Heap compaction implemented.  Previously on some programs the object
  allocation pattern could lead to a highly fragmented heap (lots of
  small holes).  This caused early heap expansion, and in some cases
  an OutOfMemory exception (a result of repeated heap expansion until
  heap fully expanded).

  JamVM now includes a mark/compact collector in addition to the
  mark/sweep GC.  This is normally ran after forced finalisation, and
  before heap expansion.  It removes fragmentation by sliding the objects
  to the bottom of the heap, closing the holes.

  Two new command line options can be used to control compaction :

    -Xnocompact : don't do compaction and just use the mark/sweep
                  collector.  This is equivalent to JamVM 1.4.2 behaviour.

    -Xcompactalways : do compaction on every garbage-collection.   In
                      some cases this may lead to less collections, but
                      the compactor is slower than the sweeper.

- The interned String table is now garbage-collected (JamVM uses its
  own interned String hashtable).

- Additional Java 1.5 support
    - New methods within VMClass implemented
        - isMemberClass, isLocalClass, isAnonymousClass,
          getEnclosingClass, getEnclosingMethod,
          getEnclosingConstructor, getClassSignature.

    - Generic signature support in reflection classes (Constructor, Method
      Field).
        - getTypeParameters, getSignature, getGenericExceptionTypes,
          getGenericParameterTypes, toGenericString, getGenericType,
          getGenericReturnType

    - Uncaught exceptions will now use the thread's uncaughtExceptionHandler
      (if available).

- Fix for Non-ASCII characters in class name parameter
    - affected methods Class.ForName, ClassLoader.defineClass

- Use getcwd() instead of PWD enviroment variable for user.dir
  property.  This fixes problems seen on some applications.

- Fix in VMClass.defineClass on 64-bit machines (protection domain
  parameter assumed to be 4 bytes).

- Minor interpreter optimisation in direct-mode with handler
  prefetch (reload of handler address in aload_0/getfield pair).

- Command line options -version and -showversion now prints a "Java
  compatible" version number.  This is to work with shell scripts which
  parse the output to get the Java version.

- Set the java.home property to the JAVA_HOME environment variable if set.

- Ported to Mac OS X on Intel.

- Runtime.availableProcessors implemented (Linux, Mac OS X and BSD
  systems).

- Updated to be compatible with Classpath 0.91.
    - Merged in changes to GNU Classpath's VM reference classes and
      JamVM's classes.

- Various compiler warnings.