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1
52
53 package com.go.trove.classfile;
54
55 import java.util.*;
56 import java.io.*;
57
58
66 class LineNumberTableAttr extends Attribute {
67 private List mEntries = new ArrayList();
68 private boolean mClean = false;
69
70 public LineNumberTableAttr(ConstantPool cp) {
71 super(cp, LINE_NUMBER_TABLE);
72 }
73
74 public int getLineNumber(Location start) {
75 clean();
76 int index = Collections.binarySearch(mEntries, new Entry(start, 0));
77 if (index < 0) {
78 if ((index = -index - 2) < 0) {
79 return -1;
80 }
81 }
82 return ((Entry)mEntries.get(index)).mLineNumber;
83 }
84
85 public void addEntry(Location start, int line_number) {
86 check("line number", line_number);
87 mEntries.add(new Entry(start, line_number));
88 mClean = false;
89 }
90
91 public int getLength() {
92 clean();
93 return 2 + 4 * mEntries.size();
94 }
95
96 public void writeDataTo(DataOutput dout) throws IOException {
97 int size = mEntries.size();
98 dout.writeShort(size);
99 for (int i=0; i<size; i++) {
100 Entry entry = (Entry)mEntries.get(i);
101
102 int start_pc = entry.mStart.getLocation();
103
104 check("line number table entry start PC", start_pc);
105
106 dout.writeShort(start_pc);
107 dout.writeShort(entry.mLineNumber);
108 }
109 }
110
111 private void check(String  type, int addr) throws RuntimeException {
112 if (addr < 0 || addr > 65535) {
113 throw new RuntimeException ("Value for " + type + " out of " +
114 "valid range: " + addr);
115
116 }
117 }
118
119 private void clean() {
120 if (!mClean) {
121 mClean = true;
122
123
129 Set reduced = new TreeSet();
130 for (int i = mEntries.size(); --i >= 0; ) {
131 reduced.add(mEntries.get(i));
132 }
133
134 mEntries = new ArrayList(reduced);
135 }
136 }
137
138 static Attribute define(ConstantPool cp,
139 String name,
140 int length,
141 DataInput din) throws IOException {
142
143 LineNumberTableAttr lineNumbers = new LineNumberTableAttr(cp);
144
145 int size = din.readUnsignedShort();
146 for (int i=0; i<size; i++) {
147 int start_pc = din.readUnsignedShort();
148 int line_number = din.readUnsignedShort();
149
150 lineNumbers.addEntry(new FixedLocation(start_pc), line_number);
151 }
152
153 return lineNumbers;
154 }
155
156 private static class Entry implements Comparable {
157 public final Location mStart;
158 public final int mLineNumber;
159
160 public Entry(Location start, int line_number) {
161 mStart = start;
162 mLineNumber = line_number;
163 }
164
165 public int compareTo(Object other) {
166 int thisLoc = mStart.getLocation();
167 int thatLoc = ((Entry)other).mStart.getLocation();
168
169 if (thisLoc < thatLoc) {
170 return -1;
171 }
172 else if (thisLoc > thatLoc) {
173 return 1;
174 }
175 else {
176 return 0;
177 }
178 }
179
180 public boolean equals(Object other) {
181 if (other instanceof Entry) {
182 return mStart.getLocation() ==
183 ((Entry)other).mStart.getLocation();
184 }
185 return false;
186 }
187
188 public String toString() {
189 return "start_pc=" + mStart.getLocation() + " => " +
190 "line_number=" + mLineNumber;
191 }
192 }
193 }
194 |
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