| /* |
| * This file is part of the Jikes RVM project (http://jikesrvm.org). |
| * |
| * This file is licensed to You under the Eclipse Public License (EPL); |
| * You may not use this file except in compliance with the License. You |
| * may obtain a copy of the License at |
| * |
| * http://www.opensource.org/licenses/eclipse-1.0.php |
| * |
| * See the COPYRIGHT.txt file distributed with this work for information |
| * regarding copyright ownership. |
| */ |
| package org.mmtk.vm; |
| |
| import org.vmmagic.pragma.Uninterruptible; |
| |
| |
| /** |
| * A counter that supports atomic increment and reset. |
| */ |
| @Uninterruptible public abstract class SynchronizedCounter { |
| |
| /** |
| * Reset the counter to 0, returning its previous value. |
| * |
| * @return The value of the counter, prior to reset. |
| */ |
| public abstract int reset(); |
| |
| /** |
| * Adds 1 to the counter. |
| * |
| * @return the value before the add |
| */ |
| public abstract int increment(); |
| |
| /** |
| * Peek at the counter |
| * |
| * @return The current value of the counter. |
| */ |
| public abstract int peek(); |
| } |