001 /* 002 Copyright (C) 2004 Laurent Martelli <laurent@aopsys.com> 003 004 This program is free software; you can redistribute it and/or modify 005 it under the terms of the GNU Lesser General Public License as 006 published by the Free Software Foundation; either version 2 of the 007 License, or (at your option) any later version. 008 009 This program is distributed in the hope that it will be useful, 010 but WITHOUT ANY WARRANTY; without even the implied warranty of 011 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 012 GNU Lesser General Public License for more details. 013 014 You should have received a copy of the GNU Lesser General Public License 015 along with this program; if not, write to the Free Software 016 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ 017 018 package org.objectweb.jac.aspects.cache; 019 020 import java.util.Hashtable; 021 import org.apache.log4j.Logger; 022 import org.objectweb.jac.aspects.timestamp.Timestamps; 023 import org.objectweb.jac.util.ObjectArray; 024 025 public class MethodCache extends Hashtable { 026 static final Logger logger = Logger.getLogger("cache"); 027 028 public MethodCache(Timestamps stamps) { 029 this.stamps = stamps; 030 } 031 032 Timestamps stamps; 033 public Entry getEntry(ObjectArray args, int[] ignoredArgs) { 034 Object[] argsArray = args.getArray(); 035 if (ignoredArgs!=null) { 036 for (int i=0; i<ignoredArgs.length; i++) { 037 argsArray[ignoredArgs[i]] = null; 038 } 039 } 040 Entry entry = (Entry)get(args); 041 if (entry!=null) { 042 logger.debug(" cache hit "+args.hashCode()); 043 if (stamps!=null) { 044 int argCount = argsArray.length; 045 long entryTime = entry.time; 046 int i; 047 for (i=0; i<argCount; i++) { 048 Object arg = argsArray[i]; 049 if (arg!=null) { 050 long mtime = stamps.getStamp(arg); 051 if (mtime > entryTime) { 052 logger.debug( 053 " outdated for arg "+i+": "+ 054 mtime+">"+entryTime); 055 break; 056 } 057 } 058 } 059 if (i==argCount) // we didn't break in the middle 060 return (Entry)get(args); 061 else 062 return null; 063 } else { 064 return ((Entry)get(args)); 065 } 066 } else { 067 logger.debug(" cache miss "+args.hashCode()); 068 return null; 069 } 070 } 071 072 public void putEntry(ObjectArray args, Object value) { 073 put(args,new Entry(value)); 074 } 075 076 public static class Entry { 077 long time; 078 public Object value; 079 public Entry(Object value) { 080 this.value = value; 081 this.time = System.currentTimeMillis(); 082 } 083 } 084 }