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1
25
26 package org.netbeans.modules.classfile;
27
28 import java.io.*;
29
30
37 public final class ConstantPoolReader extends FilterInputStream implements DataInput {
38
39 public ConstantPoolReader(InputStream in) {
40 super(in);
41 }
42
43 public void readFully(byte[] b) throws IOException {
44 readFully(b, 0, b.length);
45 }
46
47 public void readFully(byte[] b, int off, int len) throws IOException {
48 InputStream in = this.in;
49 int n = 0;
50 while (n < len) {
51 int count = in.read(b, off + n, len - n);
52 if (count < 0)
53 throw new EOFException();
54 n += count;
55 }
56 }
57
58 public int skipBytes(int n) throws IOException {
59 InputStream in = this.in;
60 int total = 0;
61 int cur = 0;
62
63 while ((total<n) && ((cur = (int) in.skip(n-total)) > 0)) {
64 total += cur;
65 }
66
67 return total;
68 }
69
70 public boolean readBoolean() throws IOException {
71 int ch = in.read();
72 if (ch < 0)
73 throw new EOFException();
74 return (ch != 0);
75 }
76
77 public byte readByte() throws IOException {
78 int ch = in.read();
79 if (ch < 0)
80 throw new EOFException();
81 return (byte)(ch);
82 }
83
84 public int readUnsignedByte() throws IOException {
85 int ch = in.read();
86 if (ch < 0)
87 throw new EOFException();
88 return ch;
89 }
90
91 public short readShort() throws IOException {
92 InputStream in = this.in;
93 int ch1 = in.read();
94 int ch2 = in.read();
95 if ((ch1 | ch2) < 0)
96 throw new EOFException();
97 return (short)((ch1 << 8) + ch2);
98 }
99
100 public int readUnsignedShort() throws IOException {
101 InputStream in = this.in;
102 int ch1 = in.read();
103 int ch2 = in.read();
104 if ((ch1 | ch2) < 0)
105 throw new EOFException();
106 return (ch1 << 8) + ch2;
107 }
108
109 public char readChar() throws IOException {
110 return (char)readUnsignedShort();
111 }
112
113 public int readInt() throws IOException {
114 InputStream in = this.in;
115 int ch1 = in.read();
116 int ch2 = in.read();
117 int ch3 = in.read();
118 int ch4 = in.read();
119 if ((ch1 | ch2 | ch3 | ch4) < 0)
120 throw new EOFException();
121 return ((ch1 << 24) + (ch2 << 16) + (ch3 << 8) + ch4);
122 }
123
124 public long readLong() throws IOException {
125 return ((long)(readInt()) << 32) + (readInt() & 0xFFFFFFFFL);
126 }
127
128 public float readFloat() throws IOException {
129 return Float.intBitsToFloat(readInt());
130 }
131
132 public double readDouble() throws IOException {
133 return Double.longBitsToDouble(readLong());
134 }
135
136 private char[] lineBuffer;
137
138 public String  readLine() throws IOException {
139 InputStream in = this.in;
140 char buf[] = lineBuffer;
141
142 if (buf == null) {
143 buf = lineBuffer = new char[128];
144 }
145
146 int room = buf.length;
147 int offset = 0;
148 int c;
149
150 loop: while (true) {
151 switch (c = in.read()) {
152 case -1:
153 case '\n':
154 break loop;
155
156 case '\r':
157 int c2 = in.read();
158 if ((c2 != '\n') && (c2 != -1)) {
159 if (!(in instanceof PushbackInputStream)) {
160 in = this.in = new PushbackInputStream(in);
161 }
162 ((PushbackInputStream)in).unread(c2);
163 }
164 break loop;
165
166 default:
167 if (--room < 0) {
168 buf = new char[offset + 128];
169 room = buf.length - offset - 1;
170 System.arraycopy(lineBuffer, 0, buf, 0, offset);
171 lineBuffer = buf;
172 }
173 buf[offset++] = (char) c;
174 break;
175 }
176 }
177 if ((c == -1) && (offset == 0)) {
178 return null;
179 }
180 return String.copyValueOf(buf, 0, offset);
181 }
182
183 static char[] str = new char[1024];
185 byte[] bytearr = new byte[1024];
186
187 public String readUTF() throws IOException {
188 int utflen = readUnsignedShort();
189 if (utflen > bytearr.length)
190 bytearr = new byte[utflen];
191
192 readFully(bytearr, 0, utflen);
193 return readUTF(bytearr, utflen);
194 }
195
196 byte[] readRawUTF() throws IOException {
197 int utflen = readUnsignedShort();
198 byte[] buf = new byte[utflen];
199 readFully(buf, 0, utflen);
200 return buf;
201 }
202
203 static synchronized String readUTF(byte[] src, int utflen) {
204 int i = 0;
205 int strlen = 0;
206
207 if (utflen > str.length)
208 str = new char[utflen];
209
210 while (i < utflen) {
211 int b = src[i++] & 0xFF;
212 if (b >= 0xE0) {
213 b = (b & 0x0F) << 12;
214 b |= (src[i++] & 0x3F) << 6;
215 b |= (src[i++] & 0x3F);
216 } else if (b >= 0xC0) {
217 b = (b & 0x1F) << 6;
218 b |= (src[i++] & 0x3F);
219 }
220 str[strlen++] = (char)b;
221 }
222
223 return new String (str, 0, strlen);
225 }
226 }
227 |
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