// Meta - a "minimal" approach to adding meta-level to Java objects

sclass Meta implements IMeta {
  // We allocate one extra field for each Java object to make it
  // reasoning-compatible. We couldn't go for 0 extra fields and
  // there are no half fields in Java... so there you go.
  // Also, if you don't use any meta data, you are probably not
  // reasoning about anything. The point of reasoning in JavaX is
  // to attach information to objects directly used in the program.
  
  // Possible information contained in the meta field:
  //   Origin, destination, security level, sender, cost center,
  //   purpose, list of reifications, ...
  
  // So here it is. THE FIELD YOU HAVE BEEN WAITING FOR
  // We also have IMeta to retrofit foreign classes (rare but
  // probably useful)
  
  ////////////
  // "meta" //
  ////////////
  
  // Generic meta value of any kind, but the typical case is it's a
  // Map with extra field values for the object etc.
  // "meta" is volatile to avoid synchronization; but you can also synchronize on
  // _tempMetaMutex() which is usually the object itself. Collections
  // and maps are exempt from using the collections's monitor as the meta
  // mutex because their monitor tends to be held for long operations
  // (e.g. cloneList). For those we use a substantially more complex
  // algorithm using a weakMap. Probably overkill. I may reconsider.
  
  volatile O meta;
  
  // The meta field is not transient, thus by default it will be
  // persisted like anything else unless you customize your object
  // to suppress or modulate this.
  
  // ...and the interface methods
  
  public void _setMeta(O meta) { this.meta = meta; }
  public O _getMeta() { ret meta; }
  
  // MOST functions are implemented in IMeta (default implementations)
}