org.vrspace.server
Class DBObject

java.lang.Object
  java.util.Observable
      org.vrspace.server.VRObject
          org.vrspace.server.DBObject

All Implemented Interfaces:

java.lang.Cloneable

Direct Known Subclasses:

PassiveDBObject, PrivateDBObject, PublicDBObject

public class DBObject

extends VRObject

DBObject defines methodes for database storage. When processing a request, sets the field value and stores itself into database, if one is specified.

Field Summary

protected DB

db

Fields inherited from class org.vrspace.server.VRObject

db_id, primitiveMap, primitives

Constructor Summary

DBObject()

DBObject(DB db)
This constructor implies autocommit, that is, sendEvent will immediately store changed object into the database.

Method Summary

void	delete(DB db) Deletes itself from the database.
java.lang.Object	get(DB db, long id) Fetches the object having db_id = id from the database db
protected void	put() store this into the database
void	put(DB db) Stores (insert/update) the object into database db
void	sendEvent(Request r) Forwards request r to other clients, listeners added by Dispatcher.

Methods inherited from class org.vrspace.server.VRObject

arrayToString, canRead, canWrite, clone, equals, fieldToText, fromString, fromText, getClassName, getField, getFields, getId, getID, getMemebers, hasField, hasMethod, isNew, newInstance, sendResponse, setField, setField, setField, setFields, setFields, setValue, stringToArray, toString, toText, toText, toText

Methods inherited from class java.util.Observable

addObserver, clearChanged, countObservers, deleteObserver, deleteObservers, hasChanged, notifyObservers, notifyObservers, setChanged

Methods inherited from class java.lang.Object

equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

db

protected DB db

Constructor Detail

DBObject

public DBObject()

DBObject

public DBObject(DB db)

This constructor implies autocommit, that is, sendEvent will immediately store changed object into the database.

Method Detail

put

public void put(DB db)
         throws java.lang.Exception

Stores (insert/update) the object into database db

Throws:

java.lang.Exception

put

protected void put()

store this into the database

get

public java.lang.Object get(DB db,
                            long id)
                     throws java.lang.Exception

Fetches the object having db_id = id from the database db

Throws:

java.lang.Exception

delete

public void delete(DB db)
            throws java.lang.Exception

Deletes itself from the database.

Throws:

java.lang.Exception

sendEvent

public void sendEvent(Request r)
               throws RequestException

Forwards request r to other clients, listeners added by Dispatcher. Sets the field r.eventName to r.eventValue. I field does not exist, forwards event anyway. Stores itself into the database if one is set. Throws RequestException if request target is another object, or if database exception occured. Calls setValue() method which actualy forwards the event.

Overrides:

sendEvent in class VRObject

Throws:

RequestException