/*
* JBoss, Home of Professional Open Source
* Copyright 2005, JBoss Inc., and individual contributors as indicated
* by the @authors tag. See the copyright.txt 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.
*/
import java.io.Serializable;
/**
* A long integer counter class.
*
* @version <tt>$Revision: 2800 $</tt>
* @author <a href="mailto:[email protected]">Jason Dillon</a>
*/ public class LongCounter implements Serializable, Cloneable {
/** The serialVersionUID */ private static final long serialVersionUID = 1615297462859270139L;
/** The current count */ private long count;
/**
* Construct a LongCounter with a starting value.
*
* @param count
* Starting value for counter.
*/ public LongCounter(final long count) { this.count = count;
}
/**
* Construct a LongCounter.
*/ public LongCounter() {
}
/**
* Increment the counter. (Optional operation)
*
* @return The incremented value of the counter.
*/ public long increment() { return ++count;
}
/**
* Decrement the counter. (Optional operation)
*
* @return The decremented value of the counter.
*/ public long decrement() { return --count;
}
/**
* Return the current value of the counter.
*
* @return The current value of the counter.
*/ public long getCount() { return count;
}
/**
* Reset the counter to zero. (Optional operation)
*/ public void reset() { this.count = 0;
}
/**
* Check if the given object is equal to this.
*
* @param obj
* Object to test equality with.
* @return True if object is equal to this.
*/ public boolean equals(final Object obj) { if (obj == this) return true;
/**
* Return a string representation of this.
*
* @return A string representation of this.
*/ public String toString() { return String.valueOf(count);
}
/**
* Return a cloned copy of this object.
*
* @return A cloned copy of this object.
*/ public Object clone() { try { return super.clone();
} catch (CloneNotSupportedException e) { throw new InternalError();
}
}
/**
* Base wrapper class for other wrappers.
*/ private static class Wrapper extends LongCounter {
/** The serialVersionUID */ private static final long serialVersionUID = 6720507617603163762L;
/** The wrapped counter */ protected final LongCounter counter;
public Wrapper(final LongCounter counter) { this.counter = counter;
}
public long increment() { return counter.increment();
}
public long decrement() { return counter.decrement();
}
public long getCount() { return counter.getCount();
}
public void reset() {
counter.reset();
}
public boolean equals(final Object obj) { return counter.equals(obj);
}
public String toString() { return counter.toString();
}
public Object clone() { return counter.clone();
}
}
/**
* Return a synchronized counter.
*
* @param counter
* LongCounter to synchronize.
* @return Synchronized counter.
*/ public static LongCounter makeSynchronized(final LongCounter counter) { return new Wrapper(counter) {
/** The serialVersionUID */ private static final long serialVersionUID = 8903330696503363758L;
public synchronized long increment() { return this.counter.increment();
}
public synchronized long decrement() { return this.counter.decrement();
}
public synchronized long getCount() { return this.counter.getCount();
}
public synchronized void reset() { this.counter.reset();
}
public synchronized int hashCode() { return this.counter.hashCode();
}
public synchronized boolean equals(final Object obj) { return this.counter.equals(obj);
}
public synchronized String toString() { return this.counter.toString();
}
public synchronized Object clone() { return this.counter.clone();
}
};
}
/**
* Returns a directional counter.
*
* @param counter
* LongCounter to make directional.
* @param increasing
* True to create an increasing only or false to create a decreasing
* only.
* @return A directional counter.
*/ public static LongCounter makeDirectional(final LongCounter counter, final boolean increasing) {
LongCounter temp; if (increasing) {
temp = new Wrapper(counter) {
/** The serialVersionUID */ private static final long serialVersionUID = -8902748795144754375L;
public long decrement() { throw new UnsupportedOperationException();
}
public void reset() { throw new UnsupportedOperationException();
}
};
} else {
temp = new Wrapper(counter) {
/** The serialVersionUID */ private static final long serialVersionUID = 2584758778978644599L;
public long increment() { throw new UnsupportedOperationException();
}
};
}
