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1
52
53 package com.go.trove.classfile;
54
55 import java.io.*;
56
57
65 public class ExceptionHandler implements LocationRange {
66 private Location mStart;
67 private Location mEnd;
68 private Location mCatch;
69 private ConstantClassInfo mCatchType;
70
71
77 public ExceptionHandler(Location startLocation,
78 Location endLocation,
79 Location catchLocation,
80 ConstantClassInfo catchType) {
81 mStart = startLocation;
82 mEnd = endLocation;
83 mCatch = catchLocation;
84 mCatchType = catchType;
85 }
86
87 public Location getStartLocation() {
88 return mStart;
89 }
90
91 public Location getEndLocation() {
92 return mEnd;
93 }
94
95 public Location getCatchLocation() {
96 return mCatch;
97 }
98
99
102 public ConstantClassInfo getCatchType() {
103 return mCatchType;
104 }
105
106 public int compareTo(Object  obj) {
107 if (this == obj) {
108 return 0;
109 }
110
111 LocationRange other = (LocationRange)obj;
112
113 int result = getStartLocation().compareTo(other.getStartLocation());
114
115 if (result == 0) {
116 result = getEndLocation().compareTo(other.getEndLocation());
117 }
118
119 if (result == 0 && obj instanceof ExceptionHandler) {
120 result = getCatchLocation().compareTo
121 (((ExceptionHandler)other).getCatchLocation());
122 }
123
124 return result;
125 }
126
127 public void writeTo(DataOutput dout) throws IOException {
128 int start_pc = getStartLocation().getLocation();
129 int end_pc = getEndLocation().getLocation();
130 int handler_pc = getCatchLocation().getLocation();
131 int catch_type;
132 ConstantClassInfo catchType = getCatchType();
133 if (catchType == null) {
134 catch_type = 0;
135 }
136 else {
137 catch_type = catchType.getIndex();
138 }
139
140 check("exception start PC", start_pc);
141 check("exception end PC", end_pc);
142 check("exception handler PC", handler_pc);
143
144 dout.writeShort(start_pc);
145 dout.writeShort(end_pc);
146 dout.writeShort(handler_pc);
147 dout.writeShort(catch_type);
148 }
149
150 private void check(String type, int addr) throws RuntimeException {
151 if (addr < 0 || addr > 65535) {
152 throw new RuntimeException ("Value for " + type + " out of " +
153 "valid range: " + addr);
154
155 }
156 }
157
158 static ExceptionHandler readFrom(ConstantPool cp,
159 DataInput din) throws IOException {
160 int start_pc = din.readUnsignedShort();
161 int end_pc = din.readUnsignedShort();
162 int handler_pc = din.readUnsignedShort();
163 int catch_type = din.readUnsignedShort();
164
165 ConstantClassInfo catchTypeConstant;
166 if (catch_type == 0) {
167 catchTypeConstant = null;
168 }
169 else {
170 catchTypeConstant = (ConstantClassInfo)cp.getConstant(catch_type);
171 }
172
173 return new ExceptionHandler(new FixedLocation(start_pc),
174 new FixedLocation(end_pc),
175 new FixedLocation(handler_pc),
176 catchTypeConstant);
177 }
178 }
179 |
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