/*
* JBoss, Home of Professional Open Source.
* Copyright 2012, Red Hat, Inc., and individual contributors
* as indicated by the @author tags. See the copyright.txt file in the
* distribution for a full listing of individual contributors.
*
* This is free software; you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as
* published by the Free Software Foundation; either version 2.1 of
* the License, or (at your option) any later version.
*
* This software is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this software; if not, write to the Free
* Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA, or see the FSF site: http://www.fsf.org.
*/
package org.jboss.capedwarf.datastore.stats;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.ObjectOutputStream;
import java.util.concurrent.Callable;
import com.google.appengine.api.datastore.Entity;
/**
* Total stats update
*
* @author <a href="mailto:ales.justin@jboss.org">Ales Justin</a>
*/
public abstract class AbstractUpdate implements Update {
protected static enum Signum {
PLUS(1), MINUS(-1);
private final int x;
private Signum(int x) {
this.x = x;
}
}
protected final Entity trigger;
protected final Signum signum;
protected final boolean block;
protected AbstractUpdate(Entity trigger, Signum signum) {
this(trigger, signum, true);
}
protected AbstractUpdate(Entity trigger, Signum signum, boolean block) {
this.trigger = trigger;
this.signum = signum;
this.block = block;
}
public Object taskKey() {
return statsKind();
}
public boolean block() {
return block;
}
public void initialize(Entity entity) {
entity.setProperty("count", 0L);
entity.setProperty("bytes", 0L);
}
@Override
public String statsNamespace() {
return "";
}
public Entity update(Entity entity) {
Entity updated = new Entity(entity.getKind());
doUpdate(entity, updated);
return updated;
}
protected void doUpdate(Entity current, Entity newEntity) {
newEntity.setProperty("timestamp", System.currentTimeMillis());
long count = toLong(current, "count");
newEntity.setProperty("count", count + signum.x);
long bytes = toLong(current, "bytes");
newEntity.setProperty("bytes", bytes + (signum.x * countBytes(trigger)));
}
public Callable<Entity> toCallable() {
return new UpdateKeyTask(this);
}
// TODO -- better impl
protected static long countBytes(Entity entity) {
try {
ByteArrayOutputStream baos = new ByteArrayOutputStream();
ObjectOutputStream out = new ObjectOutputStream(baos);
out.writeObject(entity);
out.flush();
return baos.size();
} catch (IOException e) {
throw new IllegalArgumentException("Cannot count entity: " + entity);
}
}
protected static Long toLong(Entity entity, String property) {
Object value = entity.getProperty(property);
return (value != null) ? Number.class.cast(value).longValue() : null;
}
}