1 /*
2  * Copyright (c) 2004, 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.utilities;
26 
27 import java.util.regex.*;
28 
29 /** Provides helper routines for parsing simple C++ expressions such
30     as "(JavaThread *) 0xf00" and "Universe::_collectedHeap". */
31 
32 public class CPPExpressions {
33   private static Pattern castPattern;
34 
35   /** Represents a cast expression such as "(JavaThread *)
36       0xf00". Returns both the type to which we are casting as well as
37       the address. */
38   public static class CastExpr {
39     private String type;
40     private String address;
41 
CastExpr(String type, String address)42     private CastExpr(String type, String address) {
43       this.type = type;
44       this.address = address;
45     }
46 
getType()47     public String getType() {
48       return type;
49     }
50 
getAddress()51     public String getAddress() {
52       return address;
53     }
54   }
55 
56   /** Represents a static field expression such as "Universe::_collectedHeap". */
57   public static class StaticFieldExpr {
58     private String containingType;
59     private String fieldName;
60 
StaticFieldExpr(String containingType, String fieldName)61     private StaticFieldExpr(String containingType, String fieldName) {
62       this.containingType = containingType;
63       this.fieldName = fieldName;
64     }
65 
getContainingType()66     public String getContainingType() {
67       return containingType;
68     }
69 
getFieldName()70     public String getFieldName() {
71       return fieldName;
72     }
73   }
74 
75   /** Attempts to parse the given string into a CastExpr. Returns null
76       if the string did not match the supported pattern. */
parseCast(String expr)77   public static CastExpr parseCast(String expr) {
78     if (castPattern == null) {
79       castPattern = Pattern.compile("\\s*\\(\\s*([0-9A-Za-z:_]*)\\s*\\*\\s*\\)\\s*([0-9a-zA-Z]*)\\s*");
80     }
81     Matcher matcher = castPattern.matcher(expr);
82     if (matcher.matches()) {
83       String type = matcher.group(1);
84       String addr = matcher.group(2);
85       return new CastExpr(type, addr);
86     }
87     return null;
88   }
89 
90   /** Attempts to parse the given string into a
91       StaticFieldExpr. Returns null if the string did not match the
92       supported pattern. */
parseStaticField(String expr)93   public static StaticFieldExpr parseStaticField(String expr) {
94     String sep = "::";
95     int idx = expr.lastIndexOf(sep);
96     if (idx < 0) {
97       return null;
98     }
99     String containingType = expr.substring(0, idx);
100     String fieldName = expr.substring(idx + sep.length(), expr.length());
101     return new StaticFieldExpr(containingType, fieldName);
102   }
103 }
104