1    /* 
2     * Javassist, a Java-bytecode translator toolkit. 
3     * Copyright (C) 1999-2003 Shigeru Chiba. All Rights Reserved. 
4     * 
5     * The contents of this file are subject to the Mozilla Public License Version 
6     * 1.1 (the "License"); you may not use this file except in compliance with 
7     * the License.  Alternatively, the contents of this file may be used under 
8     * the terms of the GNU Lesser General Public License Version 2.1 or later. 
9     * 
10    * Software distributed under the License is distributed on an "AS IS" basis, 
11    * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License 
12    * for the specific language governing rights and limitations under the 
13    * License. 
14    */ 
15    
16   package javassist.compiler.ast; 
17    
18   import javassist.compiler.TokenId; 
19   import javassist.compiler.CompileError; 
20    
21   /** 
22    * Expression. 
23    */ 
24   public class Expr extends ASTList implements TokenId { 
25       /* operator must be either of: 
26        * (unary) +, (unary) -, ++, --, !, ~, 
27        * CALL, ARRAY, . (dot), MEMBER (static member access). 
28        * Otherwise, the object should be an instance of a subclass. 
29        */ 
30    
31       protected int operatorId; 
32    
33       public Expr(int op, ASTree _head, ASTList _tail) { 
34           super(_head, _tail); 
35           operatorId = op; 
36       } 
37    
38       public Expr(int op, ASTree _head) { 
39           super(_head); 
40           operatorId = op; 
41       } 
42    
43       public static Expr make(int op, ASTree oprand1, ASTree oprand2) { 
44           return new Expr(op, oprand1, new ASTList(oprand2)); 
45       } 
46    
47       public int getOperator() { 
48           return operatorId; 
49       } 
50    
51       public ASTree oprand1() { 
52           return getLeft(); 
53       } 
54    
55       public ASTree oprand2() { 
56           return getRight().getLeft(); 
57       } 
58    
59       public void accept(Visitor v) throws CompileError { 
60           v.atExpr(this); 
61       } 
62    
63       public String getName() { 
64           int id = operatorId; 
65           if (id < 128) 
66               return String.valueOf((char) id); 
67           else if (NEQ <= id && id <= ARSHIFT_E) 
68               return opNames[id - NEQ]; 
69           else if (id == INSTANCEOF) 
70               return "instanceof"; 
71           else 
72               return String.valueOf(id); 
73       } 
74    
75       protected String getTag() { 
76           return "op:" + getName(); 
77       } 
78   } 
79