All Packages  This Package  Class Hierarchy  Class Search  Index

java.lang.Object
   |
   +----utah.npm.core.Lockable
           |
           +----utah.npm.core.NPMObject
                   |
                   +----utah.npm.core.Refable
                           |
                           +----utah.npm.core.Space

Summary

public final class  Space
     extends utah.npm.core.Refable
{
          // Fields 4
     private MemPool currMemPool_;
     private Link keeperPort_;
     private Thread s_threadQ_;
     private int vmState;

          // Constructors 3
     private Space();
     public Space(Reference, MemPool);
     public Space(Reference, MemPool, int);

          // Methods 16
     private static native Space currSpace();
     public static void currentSpaceKeeperPort(Reference);
     public static void currentSpaceMemPool(Reference);
     static String typeName();

     private Class classNameException(String);
     public synchronized void destroy();
     private void lastThreadDied();
     int s_getVMState();
     private void s_init(Reference, MemPool, int);
     void s_setMemPool(MemPool);
     int s_type();
     public void startMain(String, String, String[]) throws Insanity;
     public String toString();
     private native void vmCreateSpace();
     private native void vmSpawnInitialThread(String, String, String[]);
     private int vm_MemPool();
}

Provide a virtual VM for Java applications to run in. The Space is the hook on which all of the resources for an application hang. Each thread in the system is associated with a Space. Each Space has a MemPool for its memory allocation. Each space has an (implied) namespace with fault handlers. TODO: Move the namespace stuff out of this class into a separate class Rename to Process

Version:

NPMJava 0.5.0 April, 1998

Author:

Patrick Tullmann tullmann@cs.utah.edu

Cross Reference

Returned By:

Space.currSpace()

   private int vmState

   private MemPool currMemPool_

The current MemPool threads in this space should allocate out of.

   private Link keeperPort_

A reference to a port the keeper thread for this space is waiting on.

   private Thread s_threadQ_

The head of the list of threads in this space.

Constructors

· Space

Summary  |  Top

   public Space(Reference keeperPort, 
                MemPool memPool) 

Create a new Space object with the provided KeeperPort reference and the provided MemPool.

Parameter	Description
keeperPort	a reference to a port to send Space-related requests to.
memPool	the MemPool object to link this Space to.

   public Space(Reference keeperPort, 
                MemPool memPool, 
                int hashCode) 

Create a new Space object with the provided KeeperPort reference and the provided MemPool. Give the new space the provided hash code.

Parameter	Description
keeperPort	a reference to a port to send Space-related requests to.
memPool	the MemPool object to link this Space to.
hashCode	the hash code to give this Space.

   private Space() 

A special null constructor used by the VM to bootstrap the special root Space object.

   private void s_init(Reference keeperPortRef, 
                       MemPool memPool, 
                       int hashCode) 

Private Space initialization routine. Sets the various fields in the Space to the provided values.

Parameter	Description
keeperPortRef	a reference to a port to send Space-related requests to.
memPool	the MemPool object to link this Space to.
hashCode	the hash code to give this Space.

   private native void vmCreateSpace() 

Create the VM-internal state associated with this space. This should only ever be called once for any given Space.

   private static native Space currSpace() 

Return the current thread's space object. This function is private because the Space object itself should unavailable to the threads running in it.

Returns:

the current thread's space.

   public static void currentSpaceKeeperPort(Reference out_ref) 

Return the Keeper Port reference for the current space object. TODO: rename to currentSpaceKeeperPort()

Parameter	Description
out_ref	The reference to fill in with the keeper port info.

   public static void currentSpaceMemPool(Reference out_ref) 

Return the current Space's mem pool.

Parameter	Description
out_ref	The reference to point to the MemPool.

   private native void vmSpawnInitialThread(String threadName, 
                                            String initialObj, 
                                            String[] initialArgs) 

Ask the VM to actually fire off the initial thread. Both of the parameters must be non-null (this check is done by spawnInitialThread.) Only called by startMain.

Parameter	Description
threadName	the name of the thread to be created
initialObj	the initial object to invoke the Main method of.
initialArgs	the initial arguments to pass to the main method of the initialObj.

See Also: startMain

   public void startMain(String threadName, 
                         String initialObj, 
                         String[] initialArgs)  throws Insanity

Fire up the initial thread in this space. The thread is started up executing the Main method of the given initial object with the given vector of arguments (exactly like the object name on the command line of the VM.)

Parameter	Description
threadName	the name of the first thread to start in the space.
initialObj	the name of the initial object to load and invoke the main method on.
initialArgs	the initial arguments to the main method of initialObj.

   private Class classNameException(String className) 

This method is invoked when a class isn't found in the Space. It generates a ClassNotFound fault on the Keeper port. The Keeper may respond with the name of a class to load, or just kill the Space off (as a real ClassNotFoundException would.)

This is only ever called directly by the VM.

Parameter	Description
className	the string name of the fully-qualified class to load.

Returns:

The class object to use in its place.

   private void lastThreadDied() 

This method is invoked when the last thread in the Space has died. It generates a "lastThreadDied" message to the Keeper.

This is only ever called directly by the VM.

   private int vm_MemPool() 

Return this Space's current memlimit's vmPrivate info.

This is only ever called directly by the VM.

   int s_getVMState() 

This is method simply returns the VM's private Space state associated with the object. No locking is necessary, as the vmState is never changed after it is assigned at startup. XXX not used??

Returns:

the VM-private state associated with this Space

   void s_setMemPool(MemPool pool) 

Associate the given mempool with this space.

   public synchronized void destroy() 

Overrides:

destroy in class Refable

   public String toString() 

Return a string representation of this space.

Returns:

the string "NPM Space"

Overrides:

toString in class NPMObject

   static String typeName() 

Return the string name of the Space type, "Space".

Returns:

the string "Space"

Overrides:

typeName in class NPMObject

   int s_type() 

Return the type of this object, NPMObject.SpaceType

Returns:

NPMObject.SpaceType

Overrides:

s_type in class NPMObject

See Also: NPMObject.SpaceType

All Packages  This Package  Class Hierarchy  Class Search  Index