diff options
Diffstat (limited to 'source/com/c2kernel/entity/proxy/EntityProxy.java')
| -rwxr-xr-x | source/com/c2kernel/entity/proxy/EntityProxy.java | 246 |
1 files changed, 246 insertions, 0 deletions
diff --git a/source/com/c2kernel/entity/proxy/EntityProxy.java b/source/com/c2kernel/entity/proxy/EntityProxy.java new file mode 100755 index 0000000..a5b6822 --- /dev/null +++ b/source/com/c2kernel/entity/proxy/EntityProxy.java @@ -0,0 +1,246 @@ +/**************************************************************************
+ * EntityProxy.java
+ *
+ * $Revision: 1.35 $
+ * $Date: 2005/05/10 11:40:09 $
+ *
+ * Copyright (C) 2001 CERN - European Organization for Nuclear Research
+ * All rights reserved.
+ **************************************************************************/
+
+package com.c2kernel.entity.proxy;
+
+import java.util.*;
+
+import com.c2kernel.common.ObjectNotFoundException;
+import com.c2kernel.entity.*;
+import com.c2kernel.persistency.*;
+import com.c2kernel.process.Gateway;
+import com.c2kernel.property.Property;
+import com.c2kernel.utils.*;
+
+
+/******************************************************************************
+* It is a wrapper for the connection and communication with Entities.
+* It can cache data loaded from the Entity to reduce communication with it.
+* This cache is syncronised with corresponding Entity through an event mechanism.
+*
+* @version $Revision: 1.35 $ $Date: 2005/05/10 11:40:09 $
+* @author $Author: abranson $
+******************************************************************************/
+
+abstract public class EntityProxy implements ManageableEntity
+{
+
+ protected ManageableEntity mEntity = null;
+ protected org.omg.CORBA.Object mIOR;
+ protected int mSystemKey;
+ private HashMap mSubscriptions;
+
+ /**************************************************************************
+ *
+ **************************************************************************/
+ protected EntityProxy( org.omg.CORBA.Object ior,
+ int systemKey)
+ throws ObjectNotFoundException
+ {
+ Logger.msg(8,"EntityProxy::EntityProxy() - Initialising '" +systemKey+ "' entity");
+
+ initialise( ior, systemKey);
+ }
+
+ /**************************************************************************
+ *
+ **************************************************************************/
+ private void initialise( org.omg.CORBA.Object ior,
+ int systemKey)
+ throws ObjectNotFoundException
+ {
+ Logger.msg(8, "EntityProxy::initialise() - Initialising '" +systemKey+ "' entity");
+
+ mIOR = ior;
+ mSystemKey = systemKey;
+ mSubscriptions = new HashMap();
+ }
+
+
+ /**************************************************************************
+ *
+ **************************************************************************/
+ public ManageableEntity getEntity() throws ObjectNotFoundException
+ {
+ if (mEntity == null) {
+ mEntity = narrow();
+ }
+ return mEntity;
+ }
+
+ abstract public ManageableEntity narrow() throws ObjectNotFoundException;
+
+ /**************************************************************************
+ *
+ **************************************************************************/
+ //check who is using.. and if toString() is sufficient
+ public int getSystemKey()
+ {
+ return mSystemKey;
+ }
+
+
+ /**************************************************************************
+ *
+ **************************************************************************/
+ public String queryData( String path )
+ throws ObjectNotFoundException
+ {
+
+ try {
+ Logger.msg(7, "EntityProxy.queryData() - "+mSystemKey+"/"+path);
+ if (path.endsWith("all")) {
+ Logger.msg(7, "EntityProxy.queryData() - listing contents");
+ String[] result = Gateway.getStorage().getClusterContents(mSystemKey, path.substring(0, path.length()-3));
+ StringBuffer retString = new StringBuffer();
+ for (int i = 0; i < result.length; i++) {
+ retString.append(result[i]);
+ if (i<result.length-1) retString.append(",");
+ }
+ Logger.msg(7, "EntityProxy.queryData() - "+retString.toString());
+ return retString.toString();
+ }
+ C2KLocalObject target = Gateway.getStorage().get(mSystemKey, path, null);
+ return CastorXMLUtility.marshall(target);
+ } catch (ObjectNotFoundException e) {
+ throw e;
+ } catch (Exception e) {
+ Logger.error(e);
+ return "<ERROR>"+e.getMessage()+"</ERROR>";
+ }
+ }
+
+ public String[] getContents( String path ) throws ObjectNotFoundException {
+ try {
+ return Gateway.getStorage().getClusterContents(mSystemKey, path.substring(0, path.length()));
+ } catch (ClusterStorageException e) {
+ throw new ObjectNotFoundException(e.toString());
+ }
+ }
+
+
+ /**************************************************************************
+ *
+ **************************************************************************/
+ public C2KLocalObject getObject( String xpath )
+ throws ObjectNotFoundException
+ {
+ // load from storage, falling back to proxy loader if not found in others
+ try
+ {
+ return Gateway.getStorage().get( mSystemKey, xpath , this);
+ }
+ catch( ClusterStorageException ex )
+ {
+ Logger.msg(4, "Exception loading object :"+mSystemKey+"/"+xpath);
+ throw new ObjectNotFoundException( ex.toString() );
+ }
+ }
+
+
+
+ public String getProperty( String name )
+ throws ObjectNotFoundException
+ {
+ Logger.msg(5, "Get property "+name+" from syskey/"+mSystemKey);
+ Property prop = (Property)getObject("Property/"+name);
+ try
+ {
+ return prop.getValue();
+ }
+ catch (NullPointerException ex)
+ {
+ throw new ObjectNotFoundException();
+ }
+ }
+
+ public String getName()
+ {
+ try {
+ return getProperty("Name");
+ } catch (ObjectNotFoundException ex) {
+ return null;
+ }
+ }
+
+
+ /**************************************************************************
+ * Subscription methods
+ **************************************************************************/
+
+ public void subscribe (EntityProxyObserver observer,
+ String interest,
+ boolean preload)
+ {
+ MemberSubscription newSub = new MemberSubscription(this, interest, observer, preload);
+ synchronized (this){
+ mSubscriptions.put( newSub, observer );
+ }
+ new Thread(newSub).start();
+ Logger.msg(7, "Subscribed "+observer.getClass().getName()+" for "+interest);
+ }
+
+
+ public void unsubscribe(EntityProxyObserver observer)
+ {
+ synchronized (this){
+ for (Iterator e = mSubscriptions.keySet().iterator(); e.hasNext();) {
+ MemberSubscription thisSub = (MemberSubscription)e.next();
+ if (mSubscriptions.get( thisSub ) == observer) {
+ e.remove();
+ Logger.msg(7, "Unsubscribed "+observer.getClass().getName());
+ }
+ }
+ }
+ }
+
+ public void dumpSubscriptions(int logLevel) {
+ if (mSubscriptions.size() == 0) return;
+ Logger.msg(logLevel, "Subscriptions to proxy "+mSystemKey+":");
+ synchronized(this) {
+ for (Iterator iter = mSubscriptions.keySet().iterator(); iter.hasNext();) {
+ MemberSubscription element = (MemberSubscription)iter.next();
+ EntityProxyObserver obs = element.getObserver();
+ if (obs != null)
+ Logger.msg(logLevel, " "+element.getObserver().getClass().getName()+" subscribed to "+element.interest);
+ else
+ Logger.msg(logLevel, " Phantom subscription to "+element.interest);
+ }
+ }
+ }
+
+ public void notify(ProxyMessage message) {
+ Logger.msg(4, "EntityProxy.notify() - Received change notification for "+message.getPath()+" on "+mSystemKey);
+ synchronized (this){
+ if (!message.getServer().equals(EntityProxyManager.serverName))
+ Gateway.getStorage().clearCache(mSystemKey, message.getPath());
+ for (Iterator e = mSubscriptions.keySet().iterator(); e.hasNext();) {
+ MemberSubscription newSub = (MemberSubscription)e.next();
+ if (newSub.getObserver() == null) { // phantom
+ Logger.msg(4, "Removing phantom subscription to "+newSub.interest);
+ e.remove();
+ }
+ else
+ newSub.update(message.getPath(), message.getState());
+ }
+ }
+ }
+
+ /**
+ * If this is reaped, clear out the cache for it too.
+ */
+ protected void finalize() throws Throwable {
+ Logger.msg(7, "Proxy "+mSystemKey+" reaped");
+ Gateway.getStorage().clearCache(mSystemKey, null);
+ Gateway.getProxyManager().removeProxy(mSystemKey);
+ super.finalize();
+ }
+
+}
|