1 /*
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3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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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
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24 
25 package sun.jvm.hotspot.types.basic;
26 
27 import java.util.*;
28 
29 import sun.jvm.hotspot.debugger.*;
30 import sun.jvm.hotspot.types.*;
31 
32 public abstract class BasicVtblAccess implements VtblAccess {
33   protected SymbolLookup symbolLookup;
34   protected String[] dllNames;
35 
36   private Map typeToVtblMap = new HashMap();
37 
BasicVtblAccess(SymbolLookup symbolLookup, String[] dllNames)38   public BasicVtblAccess(SymbolLookup symbolLookup,
39                          String[] dllNames) {
40     this.symbolLookup = symbolLookup;
41     this.dllNames = dllNames;
42   }
43 
44   static Object nullAddress = new Object();
45 
getVtblForType(Type type)46   public Address getVtblForType(Type type) {
47     if (type == null) {
48       return null;
49     }
50     Object result = typeToVtblMap.get(type);
51     if (result == nullAddress) {
52         return null;
53     }
54     if (result != null) {
55       return (Address)result;
56     }
57     String vtblSymbol = vtblSymbolForType(type);
58     if (vtblSymbol == null) {
59       typeToVtblMap.put(type, nullAddress);
60       return null;
61     }
62     for (int i = 0; i < dllNames.length; i++) {
63       Address addr = symbolLookup.lookup(dllNames[i], vtblSymbol);
64       if (addr != null) {
65         typeToVtblMap.put(type, addr);
66         return addr;
67       }
68     }
69     typeToVtblMap.put(type, nullAddress);
70     return null;
71   }
72 
clearCaches()73   public void clearCaches() {
74     typeToVtblMap.clear();
75   }
76 
vtblSymbolForType(Type type)77   protected abstract String vtblSymbolForType(Type type);
78 }
79