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1
24
25 package com.mckoi.database;
26
27 import java.io.DataInputStream  ;
29 import java.io.IOException ;
30 import java.io.InputStream ;
31 import java.io.DataInput ;
32
33
43
44 final class CellBufferInputStream extends InputStream implements CellInput {
45
46
51 private byte buf[];
52 private int pos;
53 private int mark = 0;
54 private int count;
55
56
59 CellBufferInputStream() {
60 this.buf = null;
61 this.pos = 0;
62 this.count = 0;
63 }
64
65
68 void setArray(byte[] new_buffer) {
69 buf = new_buffer;
70 pos = 0;
71 mark = 0;
72 count = new_buffer.length;
73 }
74
75
78 void setArray(byte[] new_buffer, int offset, int length) {
79 buf = new_buffer;
80 pos = offset;
81 mark = 0;
82 count = Math.min(new_buffer.length, length + offset);
83 }
84
85
88 public int read() {
89 return buf[pos++] & 0x0FF;
90 }
92
93 public int read(byte b[], int off, int len) {
94 if (pos >= count) {
101 return -1;
102 }
103 if (pos + len > count) {
104 len = count - pos;
105 }
106 if (len <= 0) {
107 return 0;
108 }
109 System.arraycopy(buf, pos, b, off, len);
110 pos += len;
111 return len;
112 }
113
114 public long skip(long n) {
115 if (pos + n > count) {
116 n = count - pos;
117 }
118 if (n < 0) {
119 return 0;
120 }
121 pos += n;
122 return n;
123 }
124
125 public int available() {
126 return count - pos;
127 }
128
129 public void mark(int readAheadLimit) {
130 mark = pos;
131 }
132
133 public void reset() {
134 pos = mark;
135 }
136
137 public void close() throws IOException {
138 }
139
140
141
143 public void readFully(byte[] b) throws IOException {
144 read(b, 0, b.length);
145 }
146
147 public void readFully(byte b[], int off, int len) throws IOException {
148 read(b, off, len);
149 }
150
151 public int skipBytes(int n) throws IOException {
152 return (int) skip(n);
153 }
154
155 public boolean readBoolean() throws IOException {
156 return (read() != 0);
157 }
158
159 public byte readByte() throws IOException {
160 return (byte) read();
161 }
162
163 public int readUnsignedByte() throws IOException {
164 return read();
165 }
166
167 public short readShort() throws IOException {
168 int ch1 = read();
169 int ch2 = read();
170 return (short)((ch1 << 8) + (ch2 << 0));
171 }
172
173 public int readUnsignedShort() throws IOException {
174 int ch1 = read();
175 int ch2 = read();
176 return (ch1 << 8) + (ch2 << 0);
177 }
178
179 public char readChar() throws IOException {
180 int ch1 = read();
181 int ch2 = read();
182 return (char)((ch1 << 8) + (ch2 << 0));
183 }
184
185 private char[] char_buffer = new char[8192];
186
187 public String readChars(int length) throws IOException {
188 if (length <= char_buffer.length) {
189 for (int i = 0; i < length; ++i) {
190 char_buffer[i] = (char) (((buf[pos++] & 0x0FF) << 8) +
191 ((buf[pos++] & 0x0FF) << 0));
192 }
193 return new String (char_buffer, 0, length);
194 }
195 else {
196 StringBuffer chrs = new StringBuffer (length);
197 for (int i = length; i > 0; --i) {
198 chrs.append((char) (((buf[pos++] & 0x0FF) << 8) +
199 ((buf[pos++] & 0x0FF) << 0)));
200 }
201 return new String (chrs);
202 }
203 }
204
205 public int readInt() throws IOException {
206 return ((buf[pos++] & 0x0FF) << 24) +
207 ((buf[pos++] & 0x0FF) << 16) +
208 ((buf[pos++] & 0x0FF) << 8) +
209 ((buf[pos++] & 0x0FF) << 0);
210 }
211
212 public long readLong() throws IOException {
213 return ((long)(readInt()) << 32) + (readInt() & 0xFFFFFFFFL);
214 }
215
216 public float readFloat() throws IOException {
217 return Float.intBitsToFloat(readInt());
218 }
219
220 public double readDouble() throws IOException {
221 return Double.longBitsToDouble(readLong());
222 }
223
224 public String readLine() throws IOException {
225 throw new Error ("Not implemented.");
226 }
227
228 public String readUTF() throws IOException {
229 throw new Error ("Not implemented.");
230 }
231
232
233
234
235
247 }
248 |
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