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.plan.nogc;
014    
015    import org.mmtk.plan.*;
016    
017    import org.mmtk.vm.VM;
018    
019    import org.vmmagic.pragma.*;
020    
021    /**
022     * This class implements <i>per-collector thread</i> behavior and state
023     * for the <i>NoGC</i> plan, which simply allocates (without ever collecting
024     * until the available space is exhausted.<p>
025     *
026     * Specifically, this class <i>would</i> define <i>NoGC</i> collection time semantics,
027     * however, since this plan never collects, this class consists only of stubs which
028     * may be useful as a template for implementing a basic collector.
029     *
030     * @see NoGC
031     * @see NoGCMutator
032     * @see CollectorContext
033     */
034    @Uninterruptible
035    public class NoGCCollector extends ParallelCollector {
036    
037      /************************************************************************
038       * Instance fields
039       */
040    
041      /**
042       *
043       */
044      private final NoGCTraceLocal trace = new NoGCTraceLocal(global().trace);
045      protected final TraceLocal currentTrace = trace;
046    
047    
048      /****************************************************************************
049       * Collection
050       */
051    
052      /**
053       * Perform a garbage collection
054       */
055      @Override
056      public final void collect() {
057        VM.assertions.fail("GC Triggered in NoGC Plan. Is -X:gc:ignoreSystemGC=true ?");
058      }
059    
060      @Inline
061      @Override
062      public final void collectionPhase(short phaseId, boolean primary) {
063        VM.assertions.fail("GC Triggered in NoGC Plan.");
064        /*
065        if (phaseId == NoGC.PREPARE) {
066        }
067    
068        if (phaseId == NoGC.CLOSURE) {
069        }
070    
071        if (phaseId == NoGC.RELEASE) {
072        }
073    
074        super.collectionPhase(phaseId, primary);
075        */
076      }
077    
078      /****************************************************************************
079       * Miscellaneous
080       */
081    
082      /** @return The active global plan as a <code>NoGC</code> instance. */
083      @Inline
084      private static NoGC global() {
085        return (NoGC) VM.activePlan.global();
086      }
087    
088      @Override
089      public final TraceLocal getCurrentTrace() {
090        return currentTrace;
091      }
092    }