Jake Slack | 03928ae | 2014-05-13 18:41:56 -0700 | [diff] [blame] | 1 | // |
| 2 | // ======================================================================== |
| 3 | // Copyright (c) 1995-2014 Mort Bay Consulting Pty. Ltd. |
| 4 | // ------------------------------------------------------------------------ |
| 5 | // All rights reserved. This program and the accompanying materials |
| 6 | // are made available under the terms of the Eclipse Public License v1.0 |
| 7 | // and Apache License v2.0 which accompanies this distribution. |
| 8 | // |
| 9 | // The Eclipse Public License is available at |
| 10 | // http://www.eclipse.org/legal/epl-v10.html |
| 11 | // |
| 12 | // The Apache License v2.0 is available at |
| 13 | // http://www.opensource.org/licenses/apache2.0.php |
| 14 | // |
| 15 | // You may elect to redistribute this code under either of these licenses. |
| 16 | // ======================================================================== |
| 17 | // |
| 18 | |
| 19 | package org.eclipse.jetty.io; |
| 20 | |
| 21 | import java.io.IOException; |
| 22 | import java.io.InputStream; |
| 23 | import java.io.OutputStream; |
| 24 | import java.nio.charset.Charset; |
| 25 | |
| 26 | |
| 27 | /** |
| 28 | * Byte Buffer interface. |
| 29 | * |
| 30 | * This is a byte buffer that is designed to work like a FIFO for bytes. Puts and Gets operate on different |
| 31 | * pointers into the buffer and the valid _content of the buffer is always between the getIndex and the putIndex. |
| 32 | * |
| 33 | * This buffer interface is designed to be similar, but not dependent on the java.nio buffers, which may |
| 34 | * be used to back an implementation of this Buffer. The main difference is that NIO buffer after a put have |
| 35 | * their valid _content before the position and a flip is required to access that data. |
| 36 | * |
| 37 | * For this buffer it is always true that: |
| 38 | * markValue <= getIndex <= putIndex <= capacity |
| 39 | * |
| 40 | * |
| 41 | * @version 1.0 |
| 42 | */ |
| 43 | public interface Buffer extends Cloneable |
| 44 | { |
| 45 | public final static int |
| 46 | IMMUTABLE=0, // neither indexes or contexts can be changed |
| 47 | READONLY=1, // indexes may be changed, but not content |
| 48 | READWRITE=2; // anything can be changed |
| 49 | public final boolean VOLATILE=true; // The buffer may change outside of current scope. |
| 50 | public final boolean NON_VOLATILE=false; |
| 51 | |
| 52 | /** |
| 53 | * Get the underlying array, if one exists. |
| 54 | * @return a <code>byte[]</code> backing this buffer or null if none exists. |
| 55 | */ |
| 56 | byte[] array(); |
| 57 | |
| 58 | /** |
| 59 | * |
| 60 | * @return a <code>byte[]</code> value of the bytes from the getIndex to the putIndex. |
| 61 | */ |
| 62 | byte[] asArray(); |
| 63 | |
| 64 | /** |
| 65 | * Get the underlying buffer. If this buffer wraps a backing buffer. |
| 66 | * @return The root backing buffer or this if there is no backing buffer; |
| 67 | */ |
| 68 | Buffer buffer(); |
| 69 | |
| 70 | /** |
| 71 | * |
| 72 | * @return a non volatile version of this <code>Buffer</code> value |
| 73 | */ |
| 74 | Buffer asNonVolatileBuffer(); |
| 75 | |
| 76 | /** |
| 77 | * |
| 78 | * @return a readonly version of this <code>Buffer</code>. |
| 79 | */ |
| 80 | Buffer asReadOnlyBuffer(); |
| 81 | |
| 82 | /** |
| 83 | * |
| 84 | * @return an immutable version of this <code>Buffer</code>. |
| 85 | */ |
| 86 | Buffer asImmutableBuffer(); |
| 87 | |
| 88 | /** |
| 89 | * |
| 90 | * @return an immutable version of this <code>Buffer</code>. |
| 91 | */ |
| 92 | Buffer asMutableBuffer(); |
| 93 | |
| 94 | /** |
| 95 | * |
| 96 | * The capacity of the buffer. This is the maximum putIndex that may be set. |
| 97 | * @return an <code>int</code> value |
| 98 | */ |
| 99 | int capacity(); |
| 100 | |
| 101 | /** |
| 102 | * the space remaining in the buffer. |
| 103 | * @return capacity - putIndex |
| 104 | */ |
| 105 | int space(); |
| 106 | |
| 107 | /** |
| 108 | * Clear the buffer. getIndex=0, putIndex=0. |
| 109 | */ |
| 110 | void clear(); |
| 111 | |
| 112 | /** |
| 113 | * Compact the buffer by discarding bytes before the postion (or mark if set). |
| 114 | * Bytes from the getIndex (or mark) to the putIndex are moved to the beginning of |
| 115 | * the buffer and the values adjusted accordingly. |
| 116 | */ |
| 117 | void compact(); |
| 118 | |
| 119 | /** |
| 120 | * Get the byte at the current getIndex and increment it. |
| 121 | * @return The <code>byte</code> value from the current getIndex. |
| 122 | */ |
| 123 | byte get(); |
| 124 | |
| 125 | /** |
| 126 | * Get bytes from the current postion and put them into the passed byte array. |
| 127 | * The getIndex is incremented by the number of bytes copied into the array. |
| 128 | * @param b The byte array to fill. |
| 129 | * @param offset Offset in the array. |
| 130 | * @param length The max number of bytes to read. |
| 131 | * @return The number of bytes actually read. |
| 132 | */ |
| 133 | int get(byte[] b, int offset, int length); |
| 134 | |
| 135 | /** |
| 136 | * |
| 137 | * @param length an <code>int</code> value |
| 138 | * @return a <code>Buffer</code> value |
| 139 | */ |
| 140 | Buffer get(int length); |
| 141 | |
| 142 | /** |
| 143 | * The index within the buffer that will next be read or written. |
| 144 | * @return an <code>int</code> value >=0 <= putIndex() |
| 145 | */ |
| 146 | int getIndex(); |
| 147 | |
| 148 | /** |
| 149 | * @return true of putIndex > getIndex |
| 150 | */ |
| 151 | boolean hasContent(); |
| 152 | |
| 153 | /** |
| 154 | * |
| 155 | * @return a <code>boolean</code> value true if case sensitive comparison on this buffer |
| 156 | */ |
| 157 | boolean equalsIgnoreCase(Buffer buffer); |
| 158 | |
| 159 | |
| 160 | /** |
| 161 | * |
| 162 | * @return a <code>boolean</code> value true if the buffer is immutable and that neither |
| 163 | * the buffer contents nor the indexes may be changed. |
| 164 | */ |
| 165 | boolean isImmutable(); |
| 166 | |
| 167 | /** |
| 168 | * |
| 169 | * @return a <code>boolean</code> value true if the buffer is readonly. The buffer indexes may |
| 170 | * be modified, but the buffer contents may not. For example a View onto an immutable Buffer will be |
| 171 | * read only. |
| 172 | */ |
| 173 | boolean isReadOnly(); |
| 174 | |
| 175 | /** |
| 176 | * |
| 177 | * @return a <code>boolean</code> value true if the buffer contents may change |
| 178 | * via alternate paths than this buffer. If the contents of this buffer are to be used outside of the |
| 179 | * current context, then a copy must be made. |
| 180 | */ |
| 181 | boolean isVolatile(); |
| 182 | |
| 183 | /** |
| 184 | * The number of bytes from the getIndex to the putIndex |
| 185 | * @return an <code>int</code> == putIndex()-getIndex() |
| 186 | */ |
| 187 | int length(); |
| 188 | |
| 189 | /** |
| 190 | * Set the mark to the current getIndex. |
| 191 | */ |
| 192 | void mark(); |
| 193 | |
| 194 | /** |
| 195 | * Set the mark relative to the current getIndex |
| 196 | * @param offset an <code>int</code> value to add to the current getIndex to obtain the mark value. |
| 197 | */ |
| 198 | void mark(int offset); |
| 199 | |
| 200 | /** |
| 201 | * The current index of the mark. |
| 202 | * @return an <code>int</code> index in the buffer or -1 if the mark is not set. |
| 203 | */ |
| 204 | int markIndex(); |
| 205 | |
| 206 | /** |
| 207 | * Get the byte at the current getIndex without incrementing the getIndex. |
| 208 | * @return The <code>byte</code> value from the current getIndex. |
| 209 | */ |
| 210 | byte peek(); |
| 211 | |
| 212 | /** |
| 213 | * Get the byte at a specific index in the buffer. |
| 214 | * @param index an <code>int</code> value |
| 215 | * @return a <code>byte</code> value |
| 216 | */ |
| 217 | byte peek(int index); |
| 218 | |
| 219 | /** |
| 220 | * |
| 221 | * @param index an <code>int</code> value |
| 222 | * @param length an <code>int</code> value |
| 223 | * @return The <code>Buffer</code> value from the requested getIndex. |
| 224 | */ |
| 225 | Buffer peek(int index, int length); |
| 226 | |
| 227 | /** |
| 228 | * |
| 229 | * @param index an <code>int</code> value |
| 230 | * @param b The byte array to peek into |
| 231 | * @param offset The offset into the array to start peeking |
| 232 | * @param length an <code>int</code> value |
| 233 | * @return The number of bytes actually peeked |
| 234 | */ |
| 235 | int peek(int index, byte[] b, int offset, int length); |
| 236 | |
| 237 | /** |
| 238 | * Put the contents of the buffer at the specific index. |
| 239 | * @param index an <code>int</code> value |
| 240 | * @param src a <code>Buffer</code>. If the source buffer is not modified |
| 241 | |
| 242 | * @return The number of bytes actually poked |
| 243 | */ |
| 244 | int poke(int index, Buffer src); |
| 245 | |
| 246 | /** |
| 247 | * Put a specific byte to a specific getIndex. |
| 248 | * @param index an <code>int</code> value |
| 249 | * @param b a <code>byte</code> value |
| 250 | */ |
| 251 | void poke(int index, byte b); |
| 252 | |
| 253 | /** |
| 254 | * Put a specific byte to a specific getIndex. |
| 255 | * @param index an <code>int</code> value |
| 256 | * @param b a <code>byte array</code> value |
| 257 | * @return The number of bytes actually poked |
| 258 | */ |
| 259 | int poke(int index, byte b[], int offset, int length); |
| 260 | |
| 261 | /** |
| 262 | * Write the bytes from the source buffer to the current getIndex. |
| 263 | * @param src The source <code>Buffer</code> it is not modified. |
| 264 | * @return The number of bytes actually poked |
| 265 | */ |
| 266 | int put(Buffer src); |
| 267 | |
| 268 | /** |
| 269 | * Put a byte to the current getIndex and increment the getIndex. |
| 270 | * @param b a <code>byte</code> value |
| 271 | */ |
| 272 | void put(byte b); |
| 273 | |
| 274 | /** |
| 275 | * Put a byte to the current getIndex and increment the getIndex. |
| 276 | * @param b a <code>byte</code> value |
| 277 | * @return The number of bytes actually poked |
| 278 | */ |
| 279 | int put(byte[] b,int offset, int length); |
| 280 | |
| 281 | /** |
| 282 | * Put a byte to the current getIndex and increment the getIndex. |
| 283 | * @param b a <code>byte</code> value |
| 284 | * @return The number of bytes actually poked |
| 285 | */ |
| 286 | int put(byte[] b); |
| 287 | |
| 288 | /** |
| 289 | * The index of the first element that should not be read. |
| 290 | * @return an <code>int</code> value >= getIndex() |
| 291 | */ |
| 292 | int putIndex(); |
| 293 | |
| 294 | /** |
| 295 | * Reset the current getIndex to the mark |
| 296 | */ |
| 297 | void reset(); |
| 298 | |
| 299 | /** |
| 300 | * Set the buffers start getIndex. |
| 301 | * @param newStart an <code>int</code> value |
| 302 | */ |
| 303 | void setGetIndex(int newStart); |
| 304 | |
| 305 | /** |
| 306 | * Set a specific value for the mark. |
| 307 | * @param newMark an <code>int</code> value |
| 308 | */ |
| 309 | void setMarkIndex(int newMark); |
| 310 | |
| 311 | /** |
| 312 | * |
| 313 | * @param newLimit an <code>int</code> value |
| 314 | */ |
| 315 | void setPutIndex(int newLimit); |
| 316 | |
| 317 | /** |
| 318 | * Skip _content. The getIndex is updated by min(remaining(), n) |
| 319 | * @param n The number of bytes to skip |
| 320 | * @return the number of bytes skipped. |
| 321 | */ |
| 322 | int skip(int n); |
| 323 | |
| 324 | /** |
| 325 | * |
| 326 | * @return a volitile <code>Buffer</code> from the postion to the putIndex. |
| 327 | */ |
| 328 | Buffer slice(); |
| 329 | |
| 330 | /** |
| 331 | * |
| 332 | * |
| 333 | * @return a volitile <code>Buffer</code> value from the mark to the putIndex |
| 334 | */ |
| 335 | Buffer sliceFromMark(); |
| 336 | |
| 337 | /** |
| 338 | * |
| 339 | * |
| 340 | * @param length an <code>int</code> value |
| 341 | * @return a valitile <code>Buffer</code> value from the mark of the length requested. |
| 342 | */ |
| 343 | Buffer sliceFromMark(int length); |
| 344 | |
| 345 | /** |
| 346 | * |
| 347 | * @return a <code>String</code> value describing the state and contents of the buffer. |
| 348 | */ |
| 349 | String toDetailString(); |
| 350 | |
| 351 | /* ------------------------------------------------------------ */ |
| 352 | /** Write the buffer's contents to the output stream |
| 353 | * @param out |
| 354 | */ |
| 355 | void writeTo(OutputStream out) throws IOException; |
| 356 | |
| 357 | /* ------------------------------------------------------------ */ |
| 358 | /** Read the buffer's contents from the input stream |
| 359 | * @param in input stream |
| 360 | * @param max maximum number of bytes that may be read |
| 361 | * @return actual number of bytes read or -1 for EOF |
| 362 | */ |
| 363 | int readFrom(InputStream in, int max) throws IOException; |
| 364 | |
| 365 | |
| 366 | /* ------------------------------------------------------------ */ |
| 367 | String toString(String charset); |
| 368 | |
| 369 | /* ------------------------------------------------------------ */ |
| 370 | String toString(Charset charset); |
| 371 | |
| 372 | /* |
| 373 | * Buffers implementing this interface should be compared with case insensitive equals |
| 374 | * |
| 375 | */ |
| 376 | public interface CaseInsensitve |
| 377 | {} |
| 378 | |
| 379 | |
| 380 | } |