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1
21 package com.db4o;
22
23 import com.db4o.foundation.*;
24
25
31 public class YapReader implements SlotReader {
32
33 public byte[] _buffer;
35 public int _offset;
36
37
38 YapReader(){
39 }
40
41 public YapReader(int a_length){
42 _buffer = new byte[a_length];
43 }
44
45 public void seek(int offset) {
46 _offset = offset;
47 }
48
49 public final void append(byte a_byte) {
50 _buffer[_offset++] = a_byte;
51 }
52
53 public void append(byte[] a_bytes) {
54 System.arraycopy(a_bytes, 0, _buffer, _offset, a_bytes.length);
55 _offset += a_bytes.length;
56 }
57
58 final boolean containsTheSame(YapReader other) {
59 if(other != null) {
60 byte[] otherBytes = other._buffer;
61 if(_buffer == null) {
62 return otherBytes == null;
63 }
64 if(otherBytes != null && _buffer.length == otherBytes.length) {
65 int len = _buffer.length;
66 for (int i = 0; i < len; i++) {
67 if(_buffer[i] != otherBytes[i]) {
68 return false;
69 }
70 }
71 return true;
72 }
73 }
74 return false;
75 }
76
77 public void copyTo(YapReader to, int fromOffset, int toOffset, int length) {
78 System.arraycopy(_buffer, fromOffset, to._buffer, toOffset, length);
79 }
80
81 public int getLength() {
82 return _buffer.length;
83 }
84
85 public void incrementOffset(int a_by) {
86 _offset += a_by;
87 }
88
89
94 public void read(YapStream a_stream, int a_address, int addressOffset){
95 a_stream.readBytes(_buffer, a_address, addressOffset, getLength());
96 }
97
98 public final void readBegin(byte a_identifier) {
99 if (Deploy.debug) {
100 if (Deploy.brackets) {
101 if (readByte() != YapConst.YAPBEGIN) {
102 throw new RuntimeException  ("YapBytes.readBegin() YAPBEGIN expected.");
103 }
104 }
105 if (Deploy.identifiers) {
106 byte readB = readByte();
107 if (readB != a_identifier) {
108 throw new RuntimeException ("YapBytes.readBegin() wrong identifier: "+(char)readB);
109 }
110 }
111 }
112 }
113
114 public BitMap4 readBitMap(int bitCount){
115 BitMap4 map = new BitMap4(_buffer, _offset, bitCount);
116 _offset += map.marshalledLength();
117 return map;
118 }
119
120 public byte readByte() {
121 return _buffer[_offset++];
122 }
123
124 public byte[] readBytes(int a_length){
125 byte[] bytes = new byte[a_length];
126 readBytes(bytes);
127 return bytes;
128 }
129
130 void readBytes(byte[] bytes) {
131 int length = bytes.length;
132 System.arraycopy(_buffer, _offset, bytes, 0, length);
133 _offset += length;
134 }
135
136 public final YapReader readEmbeddedObject(Transaction a_trans) {
137 return a_trans.stream().readReaderByAddress(readInt(), readInt());
138 }
139
140 public void readEncrypt(YapStream a_stream, int a_address) {
141 a_stream.readBytes(_buffer, a_address, getLength());
142 a_stream.i_handlers.decrypt(this);
143 }
144
145 public void readEnd() {
146 if (Deploy.debug && Deploy.brackets) {
147 if (readByte() != YapConst.YAPEND) {
148 throw new RuntimeException ("YapBytes.readEnd() YAPEND expected");
149 }
150 }
151 }
152
153 public final int readInt() {
154 if (Deploy.debug) {
155 return YInt.readInt(this);
156 }
157
158
160 int o = (_offset += 4) - 1;
161 return (_buffer[o] & 255) | (_buffer[--o] & 255)
162 << 8 | (_buffer[--o] & 255)
163 << 16 | _buffer[--o]
164 << 24;
165
166
175 }
176
177 public long readLong() {
178 return YLong.readLong(this);
179 }
180
181 public YapReader readPayloadReader(int offset, int length){
182 YapReader payLoad = new YapReader(length);
183 System.arraycopy(_buffer,offset, payLoad._buffer, 0, length);
184 return payLoad;
185 }
186
187 void replaceWith(byte[] a_bytes) {
188 System.arraycopy(a_bytes, 0, _buffer, 0, getLength());
189 }
190
191 public String toString() {
192 try {
193 String str = "";
194 for (int i = 0; i < _buffer.length; i++) {
195 if(i > 0){
196 str += " , ";
197 }
198 str += _buffer[i];
199 }
200 return str;
201 } catch (Exception e) {
202 if(Deploy.debug || Debug.atHome) {
203 e.printStackTrace();
204 }
205 }
206 return "";
207 }
208
209 public void writeBegin(byte a_identifier) {
210 if (Deploy.debug) {
211 if (Deploy.brackets) {
212 append(YapConst.YAPBEGIN);
213 }
214 if (Deploy.identifiers) {
215 append(a_identifier);
216 }
217 }
218 }
219
220 public final void writeBitMap(BitMap4 nullBitMap) {
221 nullBitMap.writeTo(_buffer, _offset);
222 _offset += nullBitMap.marshalledLength();
223 }
224
225 public final void writeEncrypt(YapFile file, int address, int addressOffset) {
226 file.i_handlers.encrypt(this);
227 file.writeBytes(this, address, addressOffset);
228 file.i_handlers.decrypt(this);
229 }
230
231 public void writeEnd() {
232 if (Deploy.debug && Deploy.brackets) {
233 append(YapConst.YAPEND);
234 }
235 }
236
237 public final void writeInt(int a_int) {
238
239 if (Deploy.debug) {
240 YInt.writeInt(a_int, this);
241 } else {
242
243
245 int o = _offset + 4;
246 _offset = o;
247 byte[] b = _buffer;
248 b[--o] = (byte)a_int;
249 b[--o] = (byte) (a_int >>= 8);
250 b[--o] = (byte) (a_int >>= 8);
251 b[--o] = (byte) (a_int >>= 8);
252
253
259 }
260 }
261
262 public void writeIDOf(Transaction trans, Object obj) {
263 if(obj == null){
264 writeInt(0);
265 return;
266 }
267
268 if(obj instanceof YapMeta){
269 writeIDOf(trans, (YapMeta)obj);
270 return;
271 }
272
273 writeInt(((Integer )obj).intValue());
274 }
275
276 public void writeIDOf(Transaction trans, YapMeta yapMeta) {
277 if(yapMeta == null){
278 writeInt(0);
279 return;
280 }
281 yapMeta.writeOwnID(trans, this);
282 }
283
284 public void writeShortString(Transaction trans, String a_string) {
285 trans.stream().i_handlers.i_stringHandler.writeShort(a_string, this);
286 }
287
288 public void writeLong(long l) {
289 YLong.writeLong(l, this);
290 }
291
292 public void incrementIntSize() {
293 incrementOffset(YapConst.INT_LENGTH);
294 }
295
296 public int offset() {
297 return _offset;
298 }
299
300 public void offset(int offset) {
301 _offset=offset;
302 }
303
304 public void copyBytes(byte[] target,int sourceOffset,int targetOffset, int length) {
305 System.arraycopy(_buffer, sourceOffset, target, targetOffset, length);
306 }
307 }
308 |
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