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1   /*
2    * Licensed to the Apache Software Foundation (ASF) under one or more
3    * contributor license agreements.  See the NOTICE file distributed with
4    * this work for additional information regarding copyright ownership.
5    * The ASF licenses this file to You under the Apache License, Version 2.0
6    * (the "License"); you may not use this file except in compliance with
7    * the License.  You may obtain a copy of the License at
8    * 
9    *     http://www.apache.org/licenses/LICENSE-2.0
10   * 
11   * Unless required by applicable law or agreed to in writing, software 
12   * distributed under the License is distributed on an "AS IS" BASIS, 
13   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 
14   * See the License for the specific language governing permissions and 
15   * limitations under the License.
16   */
17  
18  
19  package org.apache.jdo.impl.enhancer.classfile;
20  
21  import java.util.Hashtable;
22  
23  /***
24   * Environment in which to decode the attributes of a CodeAttribute.
25   */
26  class CodeEnv {
27      /* The constant pool */
28      private ConstantPool constantPool;
29  
30      /* hash table mapping byte code offset to InsnTarget */
31      private Hashtable targets = new Hashtable(7);
32  
33      CodeEnv(ConstantPool constantPool) {
34          this.constantPool = constantPool;
35      }
36  
37      final InsnTarget getTarget(int offset) {
38          Integer off = new Integer(offset);
39          InsnTarget targ = (InsnTarget)targets.get(off);
40          if (targ == null) {
41              targ = new InsnTarget(offset);
42              targets.put(off, targ);
43          }
44          return targ;
45      }
46  
47      final InsnTarget findTarget(int offset) {
48          Integer off = new Integer(offset);
49          return (InsnTarget)targets.get(off);
50      }
51  
52      final ConstantPool pool() {
53          return constantPool;
54      }
55  }