001    /*
002     *  This file is part of the Jikes RVM project (http://jikesrvm.org).
003     *
004     *  This file is licensed to You under the Eclipse Public License (EPL);
005     *  You may not use this file except in compliance with the License. You
006     *  may obtain a copy of the License at
007     *
008     *      http://www.opensource.org/licenses/eclipse-1.0.php
009     *
010     *  See the COPYRIGHT.txt file distributed with this work for information
011     *  regarding copyright ownership.
012     */
013    package org.mmtk.vm;
014    
015    import org.vmmagic.pragma.Uninterruptible;
016    
017    /**
018     * Simple, fair locks with deadlock detection.
019     */
020    @Uninterruptible
021    public abstract class Lock {
022    
023      /**
024       * Set the name of this lock instance
025       *
026       * @param str The name of the lock (for error output).
027       */
028      public abstract void setName(String str);
029    
030      /**
031       * Try to acquire a lock and spin-wait until acquired.
032       */
033      public abstract void acquire();
034    
035      /**
036       * Perform sanity checks on the lock. For debugging.
037       *
038       * @param w Identifies the code location in the debugging output.
039       */
040      public abstract void check(int w);
041    
042      /**
043       * Release the lock by incrementing serving counter.
044       */
045      public abstract void release();
046    }