1 /*
2 * reserved comment block
3 * DO NOT REMOVE OR ALTER!
4 */
5 /*
6 * Licensed to the Apache Software Foundation (ASF) under one or more
7 * contributor license agreements. See the NOTICE file distributed with
8 * this work for additional information regarding copyright ownership.
9 * The ASF licenses this file to You under the Apache License, Version 2.0
10 * (the "License"); you may not use this file except in compliance with
11 * the License. You may obtain a copy of the License at
12 *
13 * http://www.apache.org/licenses/LICENSE-2.0
14 *
15 * Unless required by applicable law or agreed to in writing, software
16 * distributed under the License is distributed on an "AS IS" BASIS,
17 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
18 * See the License for the specific language governing permissions and
19 * limitations under the License.
20 */
21
22 package com.sun.org.apache.bcel.internal.classfile;
23
24
25 import com.sun.org.apache.bcel.internal.Constants;
26 import java.io.*;
27
28 /**
29 * This class represents a stack map entry recording the types of
30 * local variables and the the of stack items at a given byte code offset.
31 * See CLDC specification 5.3.1.2
32 *
33 * @author <A HREF="mailto:markus.dahm@berlin.de">M. Dahm</A>
34 * @see StackMap
35 * @see StackMapType
36 */
37 public final class StackMapEntry implements Cloneable {
38 private int byte_code_offset;
39 private int number_of_locals;
40 private StackMapType[] types_of_locals;
41 private int number_of_stack_items;
42 private StackMapType[] types_of_stack_items;
43 private ConstantPool constant_pool;
44
45 /**
46 * Construct object from file stream.
47 * @param file Input stream
48 * @throws IOException
49 */
50 StackMapEntry(DataInputStream file, ConstantPool constant_pool) throws IOException
51 {
52 this(file.readShort(), file.readShort(), null, -1, null, constant_pool);
53
54 types_of_locals = new StackMapType[number_of_locals];
55 for(int i=0; i < number_of_locals; i++)
56 types_of_locals[i] = new StackMapType(file, constant_pool);
57
58 number_of_stack_items = file.readShort();
59 types_of_stack_items = new StackMapType[number_of_stack_items];
60 for(int i=0; i < number_of_stack_items; i++)
61 types_of_stack_items[i] = new StackMapType(file, constant_pool);
62 }
63
64 public StackMapEntry(int byte_code_offset, int number_of_locals,
65 StackMapType[] types_of_locals,
66 int number_of_stack_items,
67 StackMapType[] types_of_stack_items,
68 ConstantPool constant_pool) {
69 this.byte_code_offset = byte_code_offset;
70 this.number_of_locals = number_of_locals;
71 this.types_of_locals = types_of_locals;
72 this.number_of_stack_items = number_of_stack_items;
73 this.types_of_stack_items = types_of_stack_items;
74 this.constant_pool = constant_pool;
75 }
76
77 /**
78 * Dump stack map entry
79 *
80 * @param file Output file stream
81 * @throws IOException
82 */
83 public final void dump(DataOutputStream file) throws IOException
84 {
85 file.writeShort(byte_code_offset);
86
87 file.writeShort(number_of_locals);
88 for(int i=0; i < number_of_locals; i++)
89 types_of_locals[i].dump(file);
90
91 file.writeShort(number_of_stack_items);
92 for(int i=0; i < number_of_stack_items; i++)
93 types_of_stack_items[i].dump(file);
94 }
95
96 /**
97 * @return String representation.
98 */
99 public final String toString() {
100 StringBuffer buf = new StringBuffer("(offset=" + byte_code_offset);
101
102 if(number_of_locals > 0) {
103 buf.append(", locals={");
104
105 for(int i=0; i < number_of_locals; i++) {
106 buf.append(types_of_locals[i]);
107 if(i < number_of_locals - 1)
108 buf.append(", ");
109 }
110
111 buf.append("}");
112 }
113
114 if(number_of_stack_items > 0) {
115 buf.append(", stack items={");
116
117 for(int i=0; i < number_of_stack_items; i++) {
118 buf.append(types_of_stack_items[i]);
119 if(i < number_of_stack_items - 1)
120 buf.append(", ");
121 }
122
123 buf.append("}");
124 }
125
126 buf.append(")");
127
128 return buf.toString();
129 }
130
131
132 public void setByteCodeOffset(int b) { byte_code_offset = b; }
133 public int getByteCodeOffset() { return byte_code_offset; }
134 public void setNumberOfLocals(int n) { number_of_locals = n; }
135 public int getNumberOfLocals() { return number_of_locals; }
136 public void setTypesOfLocals(StackMapType[] t) { types_of_locals = t; }
137 public StackMapType[] getTypesOfLocals() { return types_of_locals; }
138 public void setNumberOfStackItems(int n) { number_of_stack_items = n; }
139 public int getNumberOfStackItems() { return number_of_stack_items; }
140 public void setTypesOfStackItems(StackMapType[] t) { types_of_stack_items = t; }
141 public StackMapType[] getTypesOfStackItems() { return types_of_stack_items; }
142
143 /**
144 * @return deep copy of this object
145 */
146 public StackMapEntry copy() {
147 try {
148 return (StackMapEntry)clone();
149 } catch(CloneNotSupportedException e) {}
150
151 return null;
152 }
153
154 /**
155 * Called by objects that are traversing the nodes of the tree implicitely
156 * defined by the contents of a Java class. I.e., the hierarchy of methods,
157 * fields, attributes, etc. spawns a tree of objects.
158 *
159 * @param v Visitor object
160 */
161 public void accept(Visitor v) {
162 v.visitStackMapEntry(this);
163 }
164
165 /**
166 * @return Constant pool used by this object.
167 */
168 public final ConstantPool getConstantPool() { return constant_pool; }
169
170 /**
171 * @param constant_pool Constant pool to be used for this object.
172 */
173 public final void setConstantPool(ConstantPool constant_pool) {
174 this.constant_pool = constant_pool;
175 }
176 }