1 /*
   2  * Copyright (c) 2005, 2011, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 package sun.jvm.hotspot.memory;
  26 
  27 import java.io.*;
  28 import java.util.*;
  29 import sun.jvm.hotspot.debugger.*;
  30 import sun.jvm.hotspot.oops.*;
  31 import sun.jvm.hotspot.types.*;
  32 import sun.jvm.hotspot.runtime.*;
  33 import sun.jvm.hotspot.utilities.*;
  34 
  35 public class StringTable extends sun.jvm.hotspot.utilities.Hashtable {
  36   static {
  37     VM.registerVMInitializedObserver(new Observer() {
  38         public void update(Observable o, Object data) {
  39           initialize(VM.getVM().getTypeDataBase());
  40         }
  41       });
  42   }
  43 
  44   private static synchronized void initialize(TypeDataBase db) {
  45     Type type = db.lookupType("StringTable");
  46     theTableField  = type.getAddressField("_the_table");
  47   }
  48 
  49   // Fields
  50   private static AddressField theTableField;
  51 
  52   // Accessors
  53   public static StringTable getTheTable() {
  54     Address tmp = theTableField.getValue();
  55     return (StringTable) VMObjectFactory.newObject(StringTable.class, tmp);
  56   }
  57 
  58   public StringTable(Address addr) {
  59     super(addr);
  60   }
  61 
  62   public interface StringVisitor {
  63     public void visit(Instance string);
  64   }
  65 
  66   public void stringsDo(StringVisitor visitor) {
  67     ObjectHeap oh = VM.getVM().getObjectHeap();
  68     int numBuckets = tableSize();
  69     for (int i = 0; i < numBuckets; i++) {
  70       for (HashtableEntry e = (HashtableEntry) bucket(i); e != null;
  71            e = (HashtableEntry) e.next()) {
  72         Instance s = (Instance)oh.newOop(e.literalValue().addOffsetToAsOopHandle(0));
  73         visitor.visit(s);
  74       }
  75     }
  76   }
  77 }