jadex.rules.state.javaimpl.OAVMixedWeakState Maven / Gradle / Ivy
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Jadex Rules is a small lightweight rule engine, which currently
employs the well-known Rete algorithm for highly efficient rule
matching. Jadex rules is therefore similar to other rule engines
like JESS and Drools. Despite the similarities there are also
important differences between these systems:
* Jadex Rules is very small and
intended to be used as component
of other software. Even though rules can be specified in a Java
dialect as well as (a small variation of) the CLIPS language
its primary usage is on the API level. Jadex Rules is currently
the core component of the Jadex BDI reasoning engine.
* Jadex Rules cleanly separates between state and rule representation.
This allows the state implementation as well as the matcher to be
flexibly exchanged. Some experiments have e.g. been conducted with
a Jena representation. Regarding the matcher, it is planned to
support also the Treat algorithm, which has a lower memory footprint
than Rete.
* Jadex Rules pays close attention to rule debugging. The state as
well as the rete engine can be observed at runtime. The rule debugger
provides functionalities to execute a rule program stepwise and also
use rule breakpoints to stop the execution at those points.
package jadex.rules.state.javaimpl;
import jadex.rules.state.OAVTypeModel;
import java.util.LinkedHashMap;
import java.util.Map;
import java.util.Set;
import java.util.WeakHashMap;
/**
* An object holding the state as
* OAV triples (object, attribute, value).
*/
public class OAVMixedWeakState extends OAVAbstractState
{
//-------- attributes --------
/** The objects table (oid -> content map). */
protected Map objects;
/** The weak objects (object id -> content map). */
protected Map weakobjects;
//-------- constructors --------
/**
* Create a new empty OAV state representation.
*/
public OAVMixedWeakState(OAVTypeModel tmodel)
{
super(tmodel);
this.objects = new LinkedHashMap();
this.weakobjects = new WeakHashMap();
// this.nocheck = true;
/* new Thread(new Runnable()
{
public void run()
{
int old_dsize = 0;
int old_wsize = 0;
int old_osize = 0;
int old_ousize = 0;
int old_psize = 0;
int old_rsize = 0;
int old_tsize = 0;
while(true)
{
try
{
Thread.sleep(10000);
}
catch(InterruptedException e)
{
}
// int dsize = deletedobjects.size();
int wsize = weakobjects.size();
// int osize = objects.size();
// int ousize = objectusages.size();
// int psize = pcls!=null ? pcls.size() : 0;
// int rsize = rootobjects.size();
// int tsize = types.size();
// if(dsize>old_dsize)
// System.out.println("dsize@"+OAVMixedWeakState.this.hashCode()+": "+dsize);
if(wsize!=old_wsize)
System.out.println("wsize@"+OAVMixedWeakState.this.hashCode()+": "+wsize);
// if(osize>old_osize)
// System.out.println("osize@"+OAVMixedWeakState.this.hashCode()+": "+osize);
// if(ousize>old_ousize)
// System.out.println("ousize@"+OAVMixedWeakState.this.hashCode()+": "+ousize);
// if(psize>old_psize)
// System.out.println("psize@"+OAVMixedWeakState.this.hashCode()+": "+psize);
// if(rsize>old_rsize)
// System.out.println("rsize@"+OAVMixedWeakState.this.hashCode()+": "+rsize);
// if(tsize>old_tsize)
// System.out.println("tsize@"+OAVMixedWeakState.this.hashCode()+": "+tsize);
// Calculate number of objects per type.
// Run on synchronizator to avoid concurrent modification.
Runnable cmd = new Runnable()
{
public void run()
{
// Sum up occurrences of types.
// final Map cnts = new HashMap();
// for(Iterator it=types.values().iterator(); it.hasNext(); )
// {
// Object type = it.next();
// Integer cnt = (Integer)cnts.get(type);
// if(cnt!=null)
// cnt = new Integer(cnt.intValue()+1);
// else
// cnt = new Integer(1);
// cnts.put(type, cnt);
// }
final Map cnts = new HashMap();
for(Iterator it=weakobjects.keySet().iterator(); it.hasNext(); )
{
Object id = it.next();
Object type = getType(id);
Integer cnt = (Integer)cnts.get(type);
if(cnt!=null)
cnt = new Integer(cnt.intValue()+1);
else
cnt = new Integer(1);
cnts.put(type, cnt);
}
// Sort types by number.
Map sorted = new TreeMap(new Comparator()
{
public int compare(Object t2, Object t1)
{
int ret = ((Integer)cnts.get(t1)).intValue() - ((Integer)cnts.get(t2)).intValue();
if(ret==0 && t1!=t2)
ret = t1.hashCode() - t2.hashCode();
return ret;
}
});
sorted.putAll(cnts);
if(cnts.size()>0)
System.out.println("objects@"+OAVMixedWeakState.this.hashCode()+": "+sorted);
// try
// {
// System.out.print("checkcyc[");
// List cycles = findCycle(weakobjects.keySet());
// if(cycles!=null && cycles.size()>0)
// System.out.println("WAHHHHHHHHHH: "+cycles);
// System.out.println("]");
// }
// catch(Exception e)
// {
// e.printStackTrace();
// }
}
};
if(synchronizator!=null)
synchronizator.invokeLater(cmd);
else
cmd.run();
// old_dsize = Math.max(old_dsize, dsize);
old_wsize = wsize;//Math.max(old_wsize, wsize);
// old_osize = Math.max(old_osize, osize);
// old_ousize = Math.max(old_ousize, ousize);
// old_psize = Math.max(old_psize, psize);
// old_rsize = Math.max(old_rsize, rsize);
// old_tsize = Math.max(old_tsize, tsize);
}
}
}).start();*/
}
/**
* Ultimately remove an object (oid), when there are no more external or internal references.
*/
protected void removeObject(Object id)
{
// #ifndef MIDP
assert nocheck || generator.isId(id);
// #endif
// Remove the object itself (needs to be done before removing its references to avoid recursion)
Map content = (Map)objects.remove(id);
weakobjects.put(id, content);
// objectspertype.remove(types.get(id), id);
if(content==null)
throw new RuntimeException("Object not found: "+id);
deletedobjects.put(id, content);
assert getObjectUsages(id)==null || getObjectUsages(id).isEmpty() : getObjectUsages(id);
objectusages.remove(id);
// type will be removed in notifyEventListeners()
}
//--------- methods --------
/**
* Add an external usage of a state object (oid). This prevents
* the oav object of being garbage collected as long
* as external references are present.
* @param id The oav object id.
* @param external The user object.
*/
public void addExternalObjectUsage(Object id, Object external)
{
// #ifndef MIDP
assert nocheck || generator.isId(id);
// #endif
}
/**
* Remove an external usage of a state object (oid). This allows
* the oav object of being garbage collected when no
* further external references and no internal references
* are present.
* @param id The oav object id.
* @param external The state external object.
*/
public void removeExternalObjectUsage(Object id, Object external)
{
// #ifndef MIDP
assert nocheck || generator.isId(id);
// #endif
}
/**
* Test if an object is externally used.
* @param id The id.
* @return True, if externally used.
*/
protected boolean isExternallyUsed(Object id)
{
return weakobjects.containsKey(id);
}
//-------- internal helper classes --------
/**
* Get an object map for its id.
* @param id The id.
* @return The object map.
*/
protected Map getObject0(Object id)
{
Map ret = super.getObject0(id);
if(ret==null)
ret = (Map)weakobjects.get(id);
return ret;
}
/**
* Test if reading the object (oid) is allowed.
* Reading is allowed on removed objects as long as there are external references.
* @param id The object (oid).
* @return True, if valid.
*/
protected boolean checkValidStateObjectRead(Object id)
{
// #ifndef MIDP
assert nocheck || generator.isId(id);
// #endif
return checkValidStateObject(id) || weakobjects.containsKey(id);
}
//-------- internal object handling --------
/**
* Internally create an object.
* @param id The id.
* @return The content map of the new object.
*/
protected Map internalCreateObject(Object id)
{
Map content = new LinkedHashMap();
objects.put(id, content);
return content;
}
/**
* Remove an object from the state objects.
* @param id The id.
* @return The content map of the object.
*/
protected Map internalRemoveObject(Object id)
{
return (Map)objects.remove(id);
}
/**
* Get the object content of an object.
* @param id The id.
* @return The content map of the object.
*/
protected Map internalGetObjectContent(Object id)
{
return (Map)objects.get(id);
}
/**
* Test if an object is contained in the state.
* @param id The id.
* @return True, if object is contained.
*/
protected boolean internalContainsObject(Object id)
{
return objects.containsKey(id);
}
/**
* Test how many object are contained in the state.
* @return The number of objects.
*/
protected int internalObjectsSize()
{
return objects.size();
}
/**
* Get a set of the internal state objects.
* @return A set of the state objects.
*/
protected Set internalGetObjects()
{
return objects.keySet();
}
}