1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
|
/*
* Javassist, a Java-bytecode translator toolkit.
* Copyright (C) 1999-2006 Shigeru Chiba. All Rights Reserved.
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. Alternatively, the contents of this file may be used under
* the terms of the GNU Lesser General Public License Version 2.1 or later.
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*/
package javassist.bytecode;
import java.io.DataInputStream;
import java.io.IOException;
import java.util.Map;
/**
* <code>Exceptions_attribute</code>.
*/
public class ExceptionsAttribute extends AttributeInfo {
/**
* The name of this attribute <code>"Exceptions"</code>.
*/
public static final String tag = "Exceptions";
ExceptionsAttribute(ConstPool cp, int n, DataInputStream in)
throws IOException
{
super(cp, n, in);
}
/**
* Constructs a copy of an exceptions attribute.
*
* @param cp constant pool table.
* @param src source attribute.
*/
private ExceptionsAttribute(ConstPool cp, ExceptionsAttribute src,
Map classnames) {
super(cp, tag);
copyFrom(src, classnames);
}
/**
* Constructs a new exceptions attribute.
*
* @param cp constant pool table.
*/
public ExceptionsAttribute(ConstPool cp) {
super(cp, tag);
byte[] data = new byte[2];
data[0] = data[1] = 0; // empty
this.info = data;
}
/**
* Makes a copy. Class names are replaced according to the
* given <code>Map</code> object.
*
* @param newCp the constant pool table used by the new copy.
* @param classnames pairs of replaced and substituted
* class names. It can be <code>null</code>.
*/
public AttributeInfo copy(ConstPool newCp, Map classnames) {
return new ExceptionsAttribute(newCp, this, classnames);
}
/**
* Copies the contents from a source attribute.
* Specified class names are replaced during the copy.
*
* @param srcAttr source Exceptions attribute
* @param classnames pairs of replaced and substituted
* class names.
*/
private void copyFrom(ExceptionsAttribute srcAttr, Map classnames) {
ConstPool srcCp = srcAttr.constPool;
ConstPool destCp = this.constPool;
byte[] src = srcAttr.info;
int num = src.length;
byte[] dest = new byte[num];
dest[0] = src[0];
dest[1] = src[1]; // the number of elements.
for (int i = 2; i < num; i += 2) {
int index = ByteArray.readU16bit(src, i);
ByteArray.write16bit(srcCp.copy(index, destCp, classnames),
dest, i);
}
this.info = dest;
}
/**
* Returns <code>exception_index_table[]</code>.
*/
public int[] getExceptionIndexes() {
byte[] blist = info;
int n = blist.length;
if (n <= 2)
return null;
int[] elist = new int[n / 2 - 1];
int k = 0;
for (int j = 2; j < n; j += 2)
elist[k++] = ((blist[j] & 0xff) << 8) | (blist[j + 1] & 0xff);
return elist;
}
/**
* Returns the names of exceptions that the method may throw.
*/
public String[] getExceptions() {
byte[] blist = info;
int n = blist.length;
if (n <= 2)
return null;
String[] elist = new String[n / 2 - 1];
int k = 0;
for (int j = 2; j < n; j += 2) {
int index = ((blist[j] & 0xff) << 8) | (blist[j + 1] & 0xff);
elist[k++] = constPool.getClassInfo(index);
}
return elist;
}
/**
* Sets <code>exception_index_table[]</code>.
*/
public void setExceptionIndexes(int[] elist) {
int n = elist.length;
byte[] blist = new byte[n * 2 + 2];
ByteArray.write16bit(n, blist, 0);
for (int i = 0; i < n; ++i)
ByteArray.write16bit(elist[i], blist, i * 2 + 2);
info = blist;
}
/**
* Sets the names of exceptions that the method may throw.
*/
public void setExceptions(String[] elist) {
int n = elist.length;
byte[] blist = new byte[n * 2 + 2];
ByteArray.write16bit(n, blist, 0);
for (int i = 0; i < n; ++i)
ByteArray.write16bit(constPool.addClassInfo(elist[i]),
blist, i * 2 + 2);
info = blist;
}
/**
* Returns <code>number_of_exceptions</code>.
*/
public int tableLength() { return info.length / 2 - 1; }
/**
* Returns the value of <code>exception_index_table[nth]</code>.
*/
public int getException(int nth) {
int index = nth * 2 + 2; // nth >= 0
return ((info[index] & 0xff) << 8) | (info[index + 1] & 0xff);
}
}
|
