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1   /*
2    * Copyright  2000-2004 The Apache Software Foundation
3    *
4    *  Licensed under the Apache License, Version 2.0 (the "License"); 
5    *  you may not use this file except in compliance with the License.
6    *  You may obtain a copy of the License at
7    *
8    *      http://www.apache.org/licenses/LICENSE-2.0
9    *
10   *  Unless required by applicable law or agreed to in writing, software
11   *  distributed under the License is distributed on an "AS IS" BASIS,
12   *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13   *  See the License for the specific language governing permissions and
14   *  limitations under the License. 
15   *
16   */ 
17  package org.apache.bcel.verifier.statics;
18  
19  
20  import org.apache.bcel.generic.Type;
21  import org.apache.bcel.verifier.exc.AssertionViolatedException;
22  import org.apache.bcel.verifier.exc.LocalVariableInfoInconsistentException;
23  
24  /***
25   * A utility class holding the information about
26   * the names and the types of the local variables in
27   * a given method.
28   *
29   * @version $Id: LocalVariablesInfo.java 386056 2006-03-15 11:31:56Z tcurdt $
30   * @author Enver Haase
31   */
32  public class LocalVariablesInfo{
33  	
34  	/*** The information about the local variables is stored here. */
35  	private LocalVariableInfo[] localVariableInfos;
36  
37  	/*** The constructor. */
38  	LocalVariablesInfo(int max_locals){
39  		localVariableInfos = new LocalVariableInfo[max_locals];
40  		for (int i=0; i<max_locals; i++){
41  			localVariableInfos[i] = new LocalVariableInfo();
42  		}
43  	}
44  
45  	/*** Returns the LocalVariableInfo for the given slot. */
46  	public LocalVariableInfo getLocalVariableInfo(int slot){
47  		if (slot < 0 || slot >= localVariableInfos.length){
48  			throw new AssertionViolatedException("Slot number for local variable information out of range.");
49  		}
50  		return localVariableInfos[slot];
51  	}
52  
53  	/***
54  	 * Adds information about the local variable in slot 'slot'. Automatically 
55  	 * adds information for slot+1 if 't' is Type.LONG or Type.DOUBLE.
56  	 * @throws LocalVariableInfoInconsistentException if the new information conflicts
57  	 *         with already gathered information.
58  	 */
59  	public void add(int slot, String name, int startpc, int length, Type t) throws LocalVariableInfoInconsistentException{
60  		// The add operation on LocalVariableInfo may throw the '...Inconsistent...' exception, we don't throw it explicitely here.
61  		
62  		if (slot < 0 || slot >= localVariableInfos.length){
63  			throw new AssertionViolatedException("Slot number for local variable information out of range.");
64  		}
65  
66  		localVariableInfos[slot].add(name, startpc, length, t);
67  		if (t == Type.LONG) {
68              localVariableInfos[slot+1].add(name, startpc, length, LONG_Upper.theInstance());
69          }
70  		if (t == Type.DOUBLE) {
71              localVariableInfos[slot+1].add(name, startpc, length, DOUBLE_Upper.theInstance());
72          }
73  	}
74  }