Matthias Andreas Benkard | 261532a | 2021-12-12 20:09:27 +0100 | [diff] [blame] | 1 | package eu.mulk.jgvariant.core; |
| 2 | |
| 3 | import static java.nio.ByteOrder.LITTLE_ENDIAN; |
| 4 | |
Matthias Andreas Benkard | 261532a | 2021-12-12 20:09:27 +0100 | [diff] [blame] | 5 | import java.lang.reflect.InvocationTargetException; |
| 6 | import java.lang.reflect.RecordComponent; |
| 7 | import java.nio.ByteBuffer; |
| 8 | import java.nio.ByteOrder; |
| 9 | import java.nio.charset.Charset; |
Matthias Andreas Benkard | 31c61e7 | 2021-12-16 20:06:39 +0100 | [diff] [blame] | 10 | import java.text.ParseException; |
Matthias Andreas Benkard | 261532a | 2021-12-12 20:09:27 +0100 | [diff] [blame] | 11 | import java.util.ArrayList; |
| 12 | import java.util.Arrays; |
| 13 | import java.util.List; |
| 14 | import java.util.Optional; |
Matthias Andreas Benkard | 4e8423d | 2021-12-19 22:56:09 +0100 | [diff] [blame^] | 15 | import java.util.function.Function; |
Matthias Andreas Benkard | 25b7f90 | 2021-12-17 06:02:11 +0100 | [diff] [blame] | 16 | import org.apiguardian.api.API; |
| 17 | import org.apiguardian.api.API.Status; |
Matthias Andreas Benkard | 261532a | 2021-12-12 20:09:27 +0100 | [diff] [blame] | 18 | import org.jetbrains.annotations.Nullable; |
| 19 | |
| 20 | /** |
Matthias Andreas Benkard | 55c3481 | 2021-12-14 21:51:10 +0100 | [diff] [blame] | 21 | * Type class for decodable types. |
Matthias Andreas Benkard | 261532a | 2021-12-12 20:09:27 +0100 | [diff] [blame] | 22 | * |
| 23 | * <p>Use the {@code of*} family of constructor methods to acquire a suitable {@link Decoder} for |
| 24 | * the type you wish to decode. |
| 25 | * |
Matthias Andreas Benkard | 4c32c39 | 2021-12-12 21:23:53 +0100 | [diff] [blame] | 26 | * <p><strong>Example</strong> |
| 27 | * |
| 28 | * <p>To parse a GVariant of type {@code "a(si)"}, which is an array of pairs of {@link String} and |
| 29 | * {@code int}, you can use the following code: |
| 30 | * |
| 31 | * <pre>{@code |
Matthias Andreas Benkard | 35f7a20 | 2021-12-14 19:29:26 +0100 | [diff] [blame] | 32 | * record ExampleRecord(String s, int i) {} |
Matthias Andreas Benkard | 4c32c39 | 2021-12-12 21:23:53 +0100 | [diff] [blame] | 33 | * |
| 34 | * var decoder = |
| 35 | * Decoder.ofArray( |
| 36 | * Decoder.ofStructure( |
| 37 | * ExampleRecord.class, |
Matthias Andreas Benkard | 35f7a20 | 2021-12-14 19:29:26 +0100 | [diff] [blame] | 38 | * Decoder.ofString(UTF_8), |
| 39 | * Decoder.ofInt().withByteOrder(LITTLE_ENDIAN))); |
Matthias Andreas Benkard | 4c32c39 | 2021-12-12 21:23:53 +0100 | [diff] [blame] | 40 | * |
| 41 | * byte[] bytes = ...; |
Matthias Andreas Benkard | 35f7a20 | 2021-12-14 19:29:26 +0100 | [diff] [blame] | 42 | * List<ExampleRecord> example = decoder.decode(ByteBuffer.wrap(bytes)); |
Matthias Andreas Benkard | 4c32c39 | 2021-12-12 21:23:53 +0100 | [diff] [blame] | 43 | * }</pre> |
| 44 | * |
Matthias Andreas Benkard | 261532a | 2021-12-12 20:09:27 +0100 | [diff] [blame] | 45 | * @param <T> the type that the {@link Decoder} can decode. |
| 46 | */ |
| 47 | @SuppressWarnings("java:S1610") |
Matthias Andreas Benkard | 25b7f90 | 2021-12-17 06:02:11 +0100 | [diff] [blame] | 48 | @API(status = Status.EXPERIMENTAL) |
Matthias Andreas Benkard | 35f7a20 | 2021-12-14 19:29:26 +0100 | [diff] [blame] | 49 | public abstract class Decoder<T> { |
Matthias Andreas Benkard | 261532a | 2021-12-12 20:09:27 +0100 | [diff] [blame] | 50 | |
| 51 | private Decoder() {} |
| 52 | |
| 53 | /** |
Matthias Andreas Benkard | 31c61e7 | 2021-12-16 20:06:39 +0100 | [diff] [blame] | 54 | * Decodes a {@link ByteBuffer} holding a serialized GVariant into a value of type {@code T}. |
| 55 | * |
Matthias Andreas Benkard | 3f13b66 | 2021-12-18 18:57:37 +0100 | [diff] [blame] | 56 | * <p><strong>Note:</strong> Due to the way the GVariant serialization format works, it is |
| 57 | * important that the start and end boundaries of the passed byte slice correspond to the actual |
| 58 | * start and end of the serialized value. The format does generally not allow for the dynamic |
| 59 | * discovery of the end of the data structure. |
| 60 | * |
| 61 | * @param byteSlice a byte slice holding a serialized GVariant. |
| 62 | * @return the deserialized value. |
Matthias Andreas Benkard | 261532a | 2021-12-12 20:09:27 +0100 | [diff] [blame] | 63 | * @throws java.nio.BufferUnderflowException if the byte buffer is shorter than the requested |
| 64 | * data. |
Matthias Andreas Benkard | 31c61e7 | 2021-12-16 20:06:39 +0100 | [diff] [blame] | 65 | * @throws IllegalArgumentException if the serialized GVariant is ill-formed |
Matthias Andreas Benkard | 261532a | 2021-12-12 20:09:27 +0100 | [diff] [blame] | 66 | */ |
| 67 | public abstract T decode(ByteBuffer byteSlice); |
| 68 | |
| 69 | abstract byte alignment(); |
| 70 | |
| 71 | @Nullable |
| 72 | abstract Integer fixedSize(); |
| 73 | |
| 74 | final boolean hasFixedSize() { |
| 75 | return fixedSize() != null; |
| 76 | } |
| 77 | |
Matthias Andreas Benkard | 4c32c39 | 2021-12-12 21:23:53 +0100 | [diff] [blame] | 78 | /** |
| 79 | * Switches the input {@link ByteBuffer} to a given {@link ByteOrder} before reading from it. |
| 80 | * |
| 81 | * @param byteOrder the byte order to use. |
| 82 | * @return a new, decorated {@link Decoder}. |
| 83 | */ |
Matthias Andreas Benkard | 4e8423d | 2021-12-19 22:56:09 +0100 | [diff] [blame^] | 84 | public final Decoder<T> withByteOrder(ByteOrder byteOrder) { |
Matthias Andreas Benkard | 261532a | 2021-12-12 20:09:27 +0100 | [diff] [blame] | 85 | var delegate = this; |
| 86 | |
| 87 | return new Decoder<>() { |
| 88 | @Override |
| 89 | public byte alignment() { |
| 90 | return delegate.alignment(); |
| 91 | } |
| 92 | |
| 93 | @Override |
| 94 | public @Nullable Integer fixedSize() { |
| 95 | return delegate.fixedSize(); |
| 96 | } |
| 97 | |
| 98 | @Override |
| 99 | public T decode(ByteBuffer byteSlice) { |
| 100 | byteSlice.order(byteOrder); |
| 101 | return delegate.decode(byteSlice); |
| 102 | } |
| 103 | }; |
| 104 | } |
| 105 | |
Matthias Andreas Benkard | 4c32c39 | 2021-12-12 21:23:53 +0100 | [diff] [blame] | 106 | /** |
Matthias Andreas Benkard | 4e8423d | 2021-12-19 22:56:09 +0100 | [diff] [blame^] | 107 | * Creates a new {@link Decoder} from an existing one by applying a function to the result. |
| 108 | * |
| 109 | * @param function the function to apply. |
| 110 | * @return a new, decorated {@link Decoder}. |
| 111 | * @see java.util.stream.Stream#map |
| 112 | */ |
| 113 | public final <U> Decoder<U> map(Function<T, U> function) { |
| 114 | var delegate = this; |
| 115 | |
| 116 | return new Decoder<>() { |
| 117 | @Override |
| 118 | public byte alignment() { |
| 119 | return delegate.alignment(); |
| 120 | } |
| 121 | |
| 122 | @Override |
| 123 | public @Nullable Integer fixedSize() { |
| 124 | return delegate.fixedSize(); |
| 125 | } |
| 126 | |
| 127 | @Override |
| 128 | public U decode(ByteBuffer byteSlice) { |
| 129 | return function.apply(delegate.decode(byteSlice)); |
| 130 | } |
| 131 | }; |
| 132 | } |
| 133 | |
| 134 | /** |
Matthias Andreas Benkard | 35f7a20 | 2021-12-14 19:29:26 +0100 | [diff] [blame] | 135 | * Creates a {@link Decoder} for an {@code Array} type. |
Matthias Andreas Benkard | 4c32c39 | 2021-12-12 21:23:53 +0100 | [diff] [blame] | 136 | * |
| 137 | * @param elementDecoder a {@link Decoder} for the elements of the array. |
| 138 | * @param <U> the element type. |
| 139 | * @return a new {@link Decoder}. |
| 140 | */ |
Matthias Andreas Benkard | 35f7a20 | 2021-12-14 19:29:26 +0100 | [diff] [blame] | 141 | public static <U> Decoder<List<U>> ofArray(Decoder<U> elementDecoder) { |
Matthias Andreas Benkard | 3443018 | 2021-12-14 20:00:36 +0100 | [diff] [blame] | 142 | return new ArrayDecoder<>(elementDecoder); |
| 143 | } |
Matthias Andreas Benkard | 261532a | 2021-12-12 20:09:27 +0100 | [diff] [blame] | 144 | |
Matthias Andreas Benkard | 3443018 | 2021-12-14 20:00:36 +0100 | [diff] [blame] | 145 | /** |
Matthias Andreas Benkard | 4e8423d | 2021-12-19 22:56:09 +0100 | [diff] [blame^] | 146 | * Creates a {@link Decoder} for an {@code Array} type of element type {@code byte} into a |
| 147 | * primitive {@code byte[]} array. |
| 148 | * |
| 149 | * @return a new {@link Decoder}. |
| 150 | */ |
| 151 | public static Decoder<byte[]> ofByteArray() { |
| 152 | return new ByteArrayDecoder(); |
| 153 | } |
| 154 | |
| 155 | /** |
Matthias Andreas Benkard | 3443018 | 2021-12-14 20:00:36 +0100 | [diff] [blame] | 156 | * Creates a {@link Decoder} for a {@code Maybe} type. |
| 157 | * |
| 158 | * @param elementDecoder a {@link Decoder} for the contained element. |
| 159 | * @param <U> the element type. |
| 160 | * @return a new {@link Decoder}. |
| 161 | */ |
| 162 | public static <U> Decoder<Optional<U>> ofMaybe(Decoder<U> elementDecoder) { |
| 163 | return new MaybeDecoder<>(elementDecoder); |
| 164 | } |
Matthias Andreas Benkard | 261532a | 2021-12-12 20:09:27 +0100 | [diff] [blame] | 165 | |
Matthias Andreas Benkard | 3443018 | 2021-12-14 20:00:36 +0100 | [diff] [blame] | 166 | /** |
Matthias Andreas Benkard | 55c3481 | 2021-12-14 21:51:10 +0100 | [diff] [blame] | 167 | * Creates a {@link Decoder} for a {@code Structure} type, decoding into a {@link Record}. |
Matthias Andreas Benkard | 3443018 | 2021-12-14 20:00:36 +0100 | [diff] [blame] | 168 | * |
| 169 | * @param recordType the {@link Record} type that represents the components of the structure. |
| 170 | * @param componentDecoders a {@link Decoder} for each component of the structure. |
| 171 | * @param <U> the {@link Record} type that represents the components of the structure. |
| 172 | * @return a new {@link Decoder}. |
| 173 | */ |
| 174 | public static <U extends Record> Decoder<U> ofStructure( |
| 175 | Class<U> recordType, Decoder<?>... componentDecoders) { |
| 176 | return new StructureDecoder<>(recordType, componentDecoders); |
| 177 | } |
Matthias Andreas Benkard | 261532a | 2021-12-12 20:09:27 +0100 | [diff] [blame] | 178 | |
Matthias Andreas Benkard | 3443018 | 2021-12-14 20:00:36 +0100 | [diff] [blame] | 179 | /** |
Matthias Andreas Benkard | 55c3481 | 2021-12-14 21:51:10 +0100 | [diff] [blame] | 180 | * Creates a {@link Decoder} for a {@code Structure} type, decoding into a {@link List}. |
| 181 | * |
| 182 | * <p>Prefer {@link #ofStructure(Class, Decoder[])} if possible, which is both more type-safe and |
| 183 | * more convenient. |
| 184 | * |
| 185 | * @param componentDecoders a {@link Decoder} for each component of the structure. |
| 186 | * @return a new {@link Decoder}. |
| 187 | */ |
| 188 | public static Decoder<Object[]> ofStructure(Decoder<?>... componentDecoders) { |
| 189 | return new TupleDecoder(componentDecoders); |
| 190 | } |
| 191 | |
| 192 | /** |
Matthias Andreas Benkard | b50fcd0 | 2021-12-16 20:17:20 +0100 | [diff] [blame] | 193 | * Creates a {@link Decoder} for the {@link Variant} type. |
Matthias Andreas Benkard | 55c3481 | 2021-12-14 21:51:10 +0100 | [diff] [blame] | 194 | * |
Matthias Andreas Benkard | b50fcd0 | 2021-12-16 20:17:20 +0100 | [diff] [blame] | 195 | * <p>The contained {@link Object} can be of one of the following types: |
Matthias Andreas Benkard | 55c3481 | 2021-12-14 21:51:10 +0100 | [diff] [blame] | 196 | * |
| 197 | * <ul> |
| 198 | * <li>{@link Boolean} |
| 199 | * <li>{@link Byte} |
| 200 | * <li>{@link Short} |
| 201 | * <li>{@link Integer} |
| 202 | * <li>{@link Long} |
| 203 | * <li>{@link String} |
| 204 | * <li>{@link Optional} (a GVariant {@code Maybe} type) |
| 205 | * <li>{@link List} (a GVariant array) |
Matthias Andreas Benkard | a66b73d | 2021-12-18 19:15:52 +0100 | [diff] [blame] | 206 | * <li>{@code Object[]} (a GVariant structure) |
Matthias Andreas Benkard | b50fcd0 | 2021-12-16 20:17:20 +0100 | [diff] [blame] | 207 | * <li>{@link Variant} (a nested variant) |
Matthias Andreas Benkard | 55c3481 | 2021-12-14 21:51:10 +0100 | [diff] [blame] | 208 | * </ul> |
Matthias Andreas Benkard | 3443018 | 2021-12-14 20:00:36 +0100 | [diff] [blame] | 209 | * |
| 210 | * @return a new {@link Decoder}. |
| 211 | */ |
Matthias Andreas Benkard | 31c61e7 | 2021-12-16 20:06:39 +0100 | [diff] [blame] | 212 | public static Decoder<Variant> ofVariant() { |
Matthias Andreas Benkard | 3443018 | 2021-12-14 20:00:36 +0100 | [diff] [blame] | 213 | return new VariantDecoder(); |
| 214 | } |
Matthias Andreas Benkard | 261532a | 2021-12-12 20:09:27 +0100 | [diff] [blame] | 215 | |
Matthias Andreas Benkard | 3443018 | 2021-12-14 20:00:36 +0100 | [diff] [blame] | 216 | /** |
Matthias Andreas Benkard | b50fcd0 | 2021-12-16 20:17:20 +0100 | [diff] [blame] | 217 | * Creates a {@link Decoder} for the {@code boolean} type. |
Matthias Andreas Benkard | 3443018 | 2021-12-14 20:00:36 +0100 | [diff] [blame] | 218 | * |
| 219 | * @return a new {@link Decoder}. |
| 220 | */ |
| 221 | public static Decoder<Boolean> ofBoolean() { |
| 222 | return new BooleanDecoder(); |
| 223 | } |
Matthias Andreas Benkard | 261532a | 2021-12-12 20:09:27 +0100 | [diff] [blame] | 224 | |
Matthias Andreas Benkard | 3443018 | 2021-12-14 20:00:36 +0100 | [diff] [blame] | 225 | /** |
Matthias Andreas Benkard | 55c3481 | 2021-12-14 21:51:10 +0100 | [diff] [blame] | 226 | * Creates a {@link Decoder} for the 8-bit {@code byte} type. |
Matthias Andreas Benkard | 3443018 | 2021-12-14 20:00:36 +0100 | [diff] [blame] | 227 | * |
| 228 | * <p><strong>Note:</strong> It is often useful to apply {@link #withByteOrder(ByteOrder)} to the |
| 229 | * result of this method. |
| 230 | * |
| 231 | * @return a new {@link Decoder}. |
| 232 | */ |
| 233 | public static Decoder<Byte> ofByte() { |
| 234 | return new ByteDecoder(); |
| 235 | } |
| 236 | |
| 237 | /** |
| 238 | * Creates a {@link Decoder} for the 16-bit {@code short} type. |
| 239 | * |
| 240 | * <p><strong>Note:</strong> It is often useful to apply {@link #withByteOrder(ByteOrder)} to the |
| 241 | * result of this method. |
| 242 | * |
| 243 | * @return a new {@link Decoder}. |
| 244 | */ |
| 245 | public static Decoder<Short> ofShort() { |
| 246 | return new ShortDecoder(); |
| 247 | } |
| 248 | |
| 249 | /** |
| 250 | * Creates a {@link Decoder} for the 32-bit {@code int} type. |
| 251 | * |
| 252 | * <p><strong>Note:</strong> It is often useful to apply {@link #withByteOrder(ByteOrder)} to the |
| 253 | * result of this method. |
| 254 | * |
| 255 | * @return a new {@link Decoder}. |
| 256 | */ |
| 257 | public static Decoder<Integer> ofInt() { |
| 258 | return new IntegerDecoder(); |
| 259 | } |
| 260 | |
| 261 | /** |
| 262 | * Creates a {@link Decoder} for the 64-bit {@code long} type. |
| 263 | * |
| 264 | * <p><strong>Note:</strong> It is often useful to apply {@link #withByteOrder(ByteOrder)} to the |
| 265 | * result of this method. |
| 266 | * |
| 267 | * @return a new {@link Decoder}. |
| 268 | */ |
| 269 | public static Decoder<Long> ofLong() { |
| 270 | return new LongDecoder(); |
| 271 | } |
| 272 | |
| 273 | /** |
| 274 | * Creates a {@link Decoder} for the {@code double} type. |
| 275 | * |
| 276 | * @return a new {@link Decoder}. |
| 277 | */ |
| 278 | public static Decoder<Double> ofDouble() { |
| 279 | return new DoubleDecoder(); |
| 280 | } |
| 281 | |
| 282 | /** |
| 283 | * Creates a {@link Decoder} for the {@link String} type. |
| 284 | * |
| 285 | * <p><strong>Note:</strong> While GVariant does not prescribe any particular encoding, {@link |
| 286 | * java.nio.charset.StandardCharsets#UTF_8} is the most common choice. |
| 287 | * |
Matthias Andreas Benkard | 3f13b66 | 2021-12-18 18:57:37 +0100 | [diff] [blame] | 288 | * @param charset the {@link Charset} the string is encoded in. |
Matthias Andreas Benkard | 3443018 | 2021-12-14 20:00:36 +0100 | [diff] [blame] | 289 | * @return a new {@link Decoder}. |
| 290 | */ |
| 291 | public static Decoder<String> ofString(Charset charset) { |
| 292 | return new StringDecoder(charset); |
Matthias Andreas Benkard | 261532a | 2021-12-12 20:09:27 +0100 | [diff] [blame] | 293 | } |
| 294 | |
| 295 | private static int align(int offset, byte alignment) { |
| 296 | return offset % alignment == 0 ? offset : offset + alignment - (offset % alignment); |
| 297 | } |
| 298 | |
| 299 | private static int getIntN(ByteBuffer byteSlice) { |
| 300 | var intBytes = new byte[4]; |
| 301 | byteSlice.get(intBytes, 0, Math.min(4, byteSlice.limit())); |
| 302 | return ByteBuffer.wrap(intBytes).order(LITTLE_ENDIAN).getInt(); |
| 303 | } |
| 304 | |
| 305 | @SuppressWarnings("java:S3358") |
| 306 | private static int byteCount(int n) { |
| 307 | return n < (1 << 8) ? 1 : n < (1 << 16) ? 2 : 4; |
| 308 | } |
| 309 | |
Matthias Andreas Benkard | 3443018 | 2021-12-14 20:00:36 +0100 | [diff] [blame] | 310 | private static class ArrayDecoder<U> extends Decoder<List<U>> { |
Matthias Andreas Benkard | 261532a | 2021-12-12 20:09:27 +0100 | [diff] [blame] | 311 | |
Matthias Andreas Benkard | 3443018 | 2021-12-14 20:00:36 +0100 | [diff] [blame] | 312 | private final Decoder<U> elementDecoder; |
Matthias Andreas Benkard | 261532a | 2021-12-12 20:09:27 +0100 | [diff] [blame] | 313 | |
Matthias Andreas Benkard | 3443018 | 2021-12-14 20:00:36 +0100 | [diff] [blame] | 314 | ArrayDecoder(Decoder<U> elementDecoder) { |
| 315 | this.elementDecoder = elementDecoder; |
Matthias Andreas Benkard | 261532a | 2021-12-12 20:09:27 +0100 | [diff] [blame] | 316 | } |
| 317 | |
Matthias Andreas Benkard | 3443018 | 2021-12-14 20:00:36 +0100 | [diff] [blame] | 318 | @Override |
| 319 | public byte alignment() { |
| 320 | return elementDecoder.alignment(); |
| 321 | } |
Matthias Andreas Benkard | 261532a | 2021-12-12 20:09:27 +0100 | [diff] [blame] | 322 | |
Matthias Andreas Benkard | 3443018 | 2021-12-14 20:00:36 +0100 | [diff] [blame] | 323 | @Override |
| 324 | @Nullable |
| 325 | Integer fixedSize() { |
| 326 | return null; |
| 327 | } |
Matthias Andreas Benkard | 261532a | 2021-12-12 20:09:27 +0100 | [diff] [blame] | 328 | |
Matthias Andreas Benkard | 3443018 | 2021-12-14 20:00:36 +0100 | [diff] [blame] | 329 | @Override |
| 330 | public List<U> decode(ByteBuffer byteSlice) { |
| 331 | List<U> elements; |
| 332 | |
| 333 | var elementSize = elementDecoder.fixedSize(); |
| 334 | if (elementSize != null) { |
| 335 | // A simple C-style array. |
| 336 | elements = new ArrayList<>(byteSlice.limit() / elementSize); |
| 337 | for (int i = 0; i < byteSlice.limit(); i += elementSize) { |
| 338 | var element = elementDecoder.decode(byteSlice.slice(i, elementSize)); |
| 339 | elements.add(element); |
Matthias Andreas Benkard | 261532a | 2021-12-12 20:09:27 +0100 | [diff] [blame] | 340 | } |
Matthias Andreas Benkard | 4e8423d | 2021-12-19 22:56:09 +0100 | [diff] [blame^] | 341 | } else if (byteSlice.limit() == 0) { |
| 342 | // A degenerate zero-length array of variable width. |
| 343 | elements = List.of(); |
Matthias Andreas Benkard | 3443018 | 2021-12-14 20:00:36 +0100 | [diff] [blame] | 344 | } else { |
| 345 | // An array with aligned elements and a vector of framing offsets in the end. |
Matthias Andreas Benkard | 261532a | 2021-12-12 20:09:27 +0100 | [diff] [blame] | 346 | int framingOffsetSize = byteCount(byteSlice.limit()); |
Matthias Andreas Benkard | 3443018 | 2021-12-14 20:00:36 +0100 | [diff] [blame] | 347 | int lastFramingOffset = |
| 348 | getIntN(byteSlice.slice(byteSlice.limit() - framingOffsetSize, framingOffsetSize)); |
| 349 | int elementCount = (byteSlice.limit() - lastFramingOffset) / framingOffsetSize; |
Matthias Andreas Benkard | 261532a | 2021-12-12 20:09:27 +0100 | [diff] [blame] | 350 | |
Matthias Andreas Benkard | 3443018 | 2021-12-14 20:00:36 +0100 | [diff] [blame] | 351 | elements = new ArrayList<>(elementCount); |
Matthias Andreas Benkard | 261532a | 2021-12-12 20:09:27 +0100 | [diff] [blame] | 352 | int position = 0; |
Matthias Andreas Benkard | 3443018 | 2021-12-14 20:00:36 +0100 | [diff] [blame] | 353 | for (int i = 0; i < elementCount; i++) { |
| 354 | int framingOffset = |
| 355 | getIntN( |
| 356 | byteSlice.slice(lastFramingOffset + i * framingOffsetSize, framingOffsetSize)); |
| 357 | elements.add(elementDecoder.decode(byteSlice.slice(position, framingOffset - position))); |
| 358 | position = align(framingOffset, alignment()); |
| 359 | } |
| 360 | } |
Matthias Andreas Benkard | 261532a | 2021-12-12 20:09:27 +0100 | [diff] [blame] | 361 | |
Matthias Andreas Benkard | 3443018 | 2021-12-14 20:00:36 +0100 | [diff] [blame] | 362 | return elements; |
| 363 | } |
| 364 | } |
| 365 | |
Matthias Andreas Benkard | 4e8423d | 2021-12-19 22:56:09 +0100 | [diff] [blame^] | 366 | private static class ByteArrayDecoder extends Decoder<byte[]> { |
| 367 | |
| 368 | private static final int ELEMENT_SIZE = 1; |
| 369 | |
| 370 | @Override |
| 371 | public byte alignment() { |
| 372 | return ELEMENT_SIZE; |
| 373 | } |
| 374 | |
| 375 | @Override |
| 376 | @Nullable |
| 377 | Integer fixedSize() { |
| 378 | return null; |
| 379 | } |
| 380 | |
| 381 | @Override |
| 382 | public byte[] decode(ByteBuffer byteSlice) { |
| 383 | // A simple C-style array. |
| 384 | byte[] elements = new byte[byteSlice.limit() / ELEMENT_SIZE]; |
| 385 | byteSlice.get(elements); |
| 386 | return elements; |
| 387 | } |
| 388 | } |
| 389 | |
Matthias Andreas Benkard | 3443018 | 2021-12-14 20:00:36 +0100 | [diff] [blame] | 390 | private static class MaybeDecoder<U> extends Decoder<Optional<U>> { |
| 391 | |
| 392 | private final Decoder<U> elementDecoder; |
| 393 | |
| 394 | MaybeDecoder(Decoder<U> elementDecoder) { |
| 395 | this.elementDecoder = elementDecoder; |
| 396 | } |
| 397 | |
| 398 | @Override |
| 399 | public byte alignment() { |
| 400 | return elementDecoder.alignment(); |
| 401 | } |
| 402 | |
| 403 | @Override |
| 404 | @Nullable |
| 405 | Integer fixedSize() { |
| 406 | return null; |
| 407 | } |
| 408 | |
| 409 | @Override |
| 410 | public Optional<U> decode(ByteBuffer byteSlice) { |
| 411 | if (!byteSlice.hasRemaining()) { |
| 412 | return Optional.empty(); |
| 413 | } else { |
| 414 | if (!elementDecoder.hasFixedSize()) { |
| 415 | // Remove trailing zero byte. |
| 416 | byteSlice.limit(byteSlice.limit() - 1); |
| 417 | } |
| 418 | |
| 419 | return Optional.of(elementDecoder.decode(byteSlice)); |
| 420 | } |
| 421 | } |
| 422 | } |
| 423 | |
| 424 | private static class StructureDecoder<U extends Record> extends Decoder<U> { |
| 425 | |
Matthias Andreas Benkard | 3443018 | 2021-12-14 20:00:36 +0100 | [diff] [blame] | 426 | private final Class<U> recordType; |
Matthias Andreas Benkard | 55c3481 | 2021-12-14 21:51:10 +0100 | [diff] [blame] | 427 | private final TupleDecoder tupleDecoder; |
Matthias Andreas Benkard | 3443018 | 2021-12-14 20:00:36 +0100 | [diff] [blame] | 428 | |
| 429 | StructureDecoder(Class<U> recordType, Decoder<?>... componentDecoders) { |
| 430 | var recordComponents = recordType.getRecordComponents(); |
Matthias Andreas Benkard | 3443018 | 2021-12-14 20:00:36 +0100 | [diff] [blame] | 431 | if (componentDecoders.length != recordComponents.length) { |
| 432 | throw new IllegalArgumentException( |
| 433 | "number of decoders (%d) does not match number of structure components (%d)" |
| 434 | .formatted(componentDecoders.length, recordComponents.length)); |
| 435 | } |
| 436 | |
Matthias Andreas Benkard | 3443018 | 2021-12-14 20:00:36 +0100 | [diff] [blame] | 437 | this.recordType = recordType; |
Matthias Andreas Benkard | 55c3481 | 2021-12-14 21:51:10 +0100 | [diff] [blame] | 438 | this.tupleDecoder = new TupleDecoder(componentDecoders); |
| 439 | } |
| 440 | |
| 441 | @Override |
| 442 | public byte alignment() { |
| 443 | return tupleDecoder.alignment(); |
| 444 | } |
| 445 | |
| 446 | @Override |
| 447 | public Integer fixedSize() { |
| 448 | return tupleDecoder.fixedSize(); |
| 449 | } |
| 450 | |
| 451 | @Override |
| 452 | public U decode(ByteBuffer byteSlice) { |
| 453 | Object[] recordConstructorArguments = tupleDecoder.decode(byteSlice); |
| 454 | |
| 455 | try { |
| 456 | var recordComponentTypes = |
| 457 | Arrays.stream(recordType.getRecordComponents()) |
| 458 | .map(RecordComponent::getType) |
| 459 | .toArray(Class<?>[]::new); |
| 460 | var recordConstructor = recordType.getDeclaredConstructor(recordComponentTypes); |
| 461 | return recordConstructor.newInstance(recordConstructorArguments); |
| 462 | } catch (NoSuchMethodException |
| 463 | | InstantiationException |
| 464 | | IllegalAccessException |
| 465 | | InvocationTargetException e) { |
| 466 | throw new IllegalStateException(e); |
| 467 | } |
| 468 | } |
| 469 | } |
| 470 | |
| 471 | private static class TupleDecoder extends Decoder<Object[]> { |
| 472 | |
| 473 | private final Decoder<?>[] componentDecoders; |
| 474 | |
| 475 | TupleDecoder(Decoder<?>... componentDecoders) { |
Matthias Andreas Benkard | 3443018 | 2021-12-14 20:00:36 +0100 | [diff] [blame] | 476 | this.componentDecoders = componentDecoders; |
| 477 | } |
| 478 | |
| 479 | @Override |
| 480 | public byte alignment() { |
| 481 | return (byte) Arrays.stream(componentDecoders).mapToInt(Decoder::alignment).max().orElse(1); |
| 482 | } |
| 483 | |
| 484 | @Override |
| 485 | public Integer fixedSize() { |
| 486 | int position = 0; |
| 487 | for (var componentDecoder : componentDecoders) { |
| 488 | var fixedComponentSize = componentDecoder.fixedSize(); |
| 489 | if (fixedComponentSize == null) { |
| 490 | return null; |
| 491 | } |
| 492 | |
| 493 | position = align(position, componentDecoder.alignment()); |
| 494 | position += fixedComponentSize; |
| 495 | } |
| 496 | |
| 497 | if (position == 0) { |
| 498 | return 1; |
| 499 | } |
| 500 | |
| 501 | return align(position, alignment()); |
| 502 | } |
| 503 | |
| 504 | @Override |
Matthias Andreas Benkard | 55c3481 | 2021-12-14 21:51:10 +0100 | [diff] [blame] | 505 | public Object[] decode(ByteBuffer byteSlice) { |
Matthias Andreas Benkard | 3443018 | 2021-12-14 20:00:36 +0100 | [diff] [blame] | 506 | int framingOffsetSize = byteCount(byteSlice.limit()); |
| 507 | |
Matthias Andreas Benkard | 55c3481 | 2021-12-14 21:51:10 +0100 | [diff] [blame] | 508 | var objects = new Object[componentDecoders.length]; |
Matthias Andreas Benkard | 3443018 | 2021-12-14 20:00:36 +0100 | [diff] [blame] | 509 | |
| 510 | int position = 0; |
| 511 | int framingOffsetIndex = 0; |
| 512 | int componentIndex = 0; |
| 513 | for (var componentDecoder : componentDecoders) { |
| 514 | position = align(position, componentDecoder.alignment()); |
| 515 | |
| 516 | var fixedComponentSize = componentDecoder.fixedSize(); |
| 517 | if (fixedComponentSize != null) { |
Matthias Andreas Benkard | 55c3481 | 2021-12-14 21:51:10 +0100 | [diff] [blame] | 518 | objects[componentIndex] = |
Matthias Andreas Benkard | 3443018 | 2021-12-14 20:00:36 +0100 | [diff] [blame] | 519 | componentDecoder.decode(byteSlice.slice(position, fixedComponentSize)); |
| 520 | position += fixedComponentSize; |
| 521 | } else { |
Matthias Andreas Benkard | 55c3481 | 2021-12-14 21:51:10 +0100 | [diff] [blame] | 522 | if (componentIndex == componentDecoders.length - 1) { |
Matthias Andreas Benkard | 3443018 | 2021-12-14 20:00:36 +0100 | [diff] [blame] | 523 | // The last component never has a framing offset. |
| 524 | int endPosition = byteSlice.limit() - framingOffsetIndex * framingOffsetSize; |
Matthias Andreas Benkard | 55c3481 | 2021-12-14 21:51:10 +0100 | [diff] [blame] | 525 | objects[componentIndex] = |
Matthias Andreas Benkard | 3443018 | 2021-12-14 20:00:36 +0100 | [diff] [blame] | 526 | componentDecoder.decode(byteSlice.slice(position, endPosition - position)); |
| 527 | position = endPosition; |
Matthias Andreas Benkard | 261532a | 2021-12-12 20:09:27 +0100 | [diff] [blame] | 528 | } else { |
Matthias Andreas Benkard | 3443018 | 2021-12-14 20:00:36 +0100 | [diff] [blame] | 529 | int framingOffset = |
| 530 | getIntN( |
| 531 | byteSlice.slice( |
| 532 | byteSlice.limit() - (1 + framingOffsetIndex) * framingOffsetSize, |
| 533 | framingOffsetSize)); |
Matthias Andreas Benkard | 55c3481 | 2021-12-14 21:51:10 +0100 | [diff] [blame] | 534 | objects[componentIndex] = |
Matthias Andreas Benkard | 3443018 | 2021-12-14 20:00:36 +0100 | [diff] [blame] | 535 | componentDecoder.decode(byteSlice.slice(position, framingOffset - position)); |
| 536 | position = framingOffset; |
| 537 | ++framingOffsetIndex; |
Matthias Andreas Benkard | 261532a | 2021-12-12 20:09:27 +0100 | [diff] [blame] | 538 | } |
Matthias Andreas Benkard | 261532a | 2021-12-12 20:09:27 +0100 | [diff] [blame] | 539 | } |
| 540 | |
Matthias Andreas Benkard | 3443018 | 2021-12-14 20:00:36 +0100 | [diff] [blame] | 541 | ++componentIndex; |
Matthias Andreas Benkard | 261532a | 2021-12-12 20:09:27 +0100 | [diff] [blame] | 542 | } |
Matthias Andreas Benkard | 3443018 | 2021-12-14 20:00:36 +0100 | [diff] [blame] | 543 | |
Matthias Andreas Benkard | 55c3481 | 2021-12-14 21:51:10 +0100 | [diff] [blame] | 544 | return objects; |
Matthias Andreas Benkard | 3443018 | 2021-12-14 20:00:36 +0100 | [diff] [blame] | 545 | } |
Matthias Andreas Benkard | 261532a | 2021-12-12 20:09:27 +0100 | [diff] [blame] | 546 | } |
| 547 | |
Matthias Andreas Benkard | 31c61e7 | 2021-12-16 20:06:39 +0100 | [diff] [blame] | 548 | private static class VariantDecoder extends Decoder<Variant> { |
Matthias Andreas Benkard | 261532a | 2021-12-12 20:09:27 +0100 | [diff] [blame] | 549 | |
Matthias Andreas Benkard | 3443018 | 2021-12-14 20:00:36 +0100 | [diff] [blame] | 550 | @Override |
| 551 | public byte alignment() { |
| 552 | return 8; |
| 553 | } |
Matthias Andreas Benkard | 261532a | 2021-12-12 20:09:27 +0100 | [diff] [blame] | 554 | |
Matthias Andreas Benkard | 3443018 | 2021-12-14 20:00:36 +0100 | [diff] [blame] | 555 | @Override |
| 556 | @Nullable |
| 557 | Integer fixedSize() { |
| 558 | return null; |
| 559 | } |
| 560 | |
| 561 | @Override |
Matthias Andreas Benkard | 31c61e7 | 2021-12-16 20:06:39 +0100 | [diff] [blame] | 562 | public Variant decode(ByteBuffer byteSlice) { |
Matthias Andreas Benkard | 55c3481 | 2021-12-14 21:51:10 +0100 | [diff] [blame] | 563 | for (int i = byteSlice.limit() - 1; i >= 0; --i) { |
| 564 | if (byteSlice.get(i) != 0) { |
| 565 | continue; |
| 566 | } |
| 567 | |
Matthias Andreas Benkard | 31c61e7 | 2021-12-16 20:06:39 +0100 | [diff] [blame] | 568 | var dataBytes = byteSlice.slice(0, i); |
| 569 | var signatureBytes = byteSlice.slice(i + 1, byteSlice.limit() - (i + 1)); |
Matthias Andreas Benkard | 55c3481 | 2021-12-14 21:51:10 +0100 | [diff] [blame] | 570 | |
Matthias Andreas Benkard | 31c61e7 | 2021-12-16 20:06:39 +0100 | [diff] [blame] | 571 | Signature signature; |
| 572 | try { |
| 573 | signature = Signature.parse(signatureBytes); |
| 574 | } catch (ParseException e) { |
| 575 | throw new IllegalArgumentException(e); |
| 576 | } |
| 577 | |
| 578 | return new Variant(signature, signature.decoder().decode(dataBytes)); |
Matthias Andreas Benkard | 55c3481 | 2021-12-14 21:51:10 +0100 | [diff] [blame] | 579 | } |
| 580 | |
| 581 | throw new IllegalArgumentException("variant signature not found"); |
| 582 | } |
Matthias Andreas Benkard | 261532a | 2021-12-12 20:09:27 +0100 | [diff] [blame] | 583 | } |
| 584 | |
Matthias Andreas Benkard | 3443018 | 2021-12-14 20:00:36 +0100 | [diff] [blame] | 585 | private static class BooleanDecoder extends Decoder<Boolean> { |
Matthias Andreas Benkard | 261532a | 2021-12-12 20:09:27 +0100 | [diff] [blame] | 586 | |
Matthias Andreas Benkard | 3443018 | 2021-12-14 20:00:36 +0100 | [diff] [blame] | 587 | @Override |
| 588 | public byte alignment() { |
| 589 | return 1; |
| 590 | } |
Matthias Andreas Benkard | 261532a | 2021-12-12 20:09:27 +0100 | [diff] [blame] | 591 | |
Matthias Andreas Benkard | 3443018 | 2021-12-14 20:00:36 +0100 | [diff] [blame] | 592 | @Override |
| 593 | public Integer fixedSize() { |
| 594 | return 1; |
| 595 | } |
| 596 | |
| 597 | @Override |
| 598 | public Boolean decode(ByteBuffer byteSlice) { |
| 599 | return byteSlice.get() != 0; |
| 600 | } |
Matthias Andreas Benkard | 261532a | 2021-12-12 20:09:27 +0100 | [diff] [blame] | 601 | } |
| 602 | |
Matthias Andreas Benkard | 3443018 | 2021-12-14 20:00:36 +0100 | [diff] [blame] | 603 | private static class ByteDecoder extends Decoder<Byte> { |
Matthias Andreas Benkard | 261532a | 2021-12-12 20:09:27 +0100 | [diff] [blame] | 604 | |
Matthias Andreas Benkard | 3443018 | 2021-12-14 20:00:36 +0100 | [diff] [blame] | 605 | @Override |
| 606 | public byte alignment() { |
| 607 | return 1; |
| 608 | } |
Matthias Andreas Benkard | 261532a | 2021-12-12 20:09:27 +0100 | [diff] [blame] | 609 | |
Matthias Andreas Benkard | 3443018 | 2021-12-14 20:00:36 +0100 | [diff] [blame] | 610 | @Override |
| 611 | public Integer fixedSize() { |
| 612 | return 1; |
| 613 | } |
| 614 | |
| 615 | @Override |
| 616 | public Byte decode(ByteBuffer byteSlice) { |
| 617 | return byteSlice.get(); |
| 618 | } |
Matthias Andreas Benkard | 261532a | 2021-12-12 20:09:27 +0100 | [diff] [blame] | 619 | } |
| 620 | |
Matthias Andreas Benkard | 3443018 | 2021-12-14 20:00:36 +0100 | [diff] [blame] | 621 | private static class ShortDecoder extends Decoder<Short> { |
Matthias Andreas Benkard | 261532a | 2021-12-12 20:09:27 +0100 | [diff] [blame] | 622 | |
Matthias Andreas Benkard | 3443018 | 2021-12-14 20:00:36 +0100 | [diff] [blame] | 623 | @Override |
| 624 | public byte alignment() { |
| 625 | return 2; |
| 626 | } |
Matthias Andreas Benkard | 261532a | 2021-12-12 20:09:27 +0100 | [diff] [blame] | 627 | |
Matthias Andreas Benkard | 3443018 | 2021-12-14 20:00:36 +0100 | [diff] [blame] | 628 | @Override |
| 629 | public Integer fixedSize() { |
| 630 | return 2; |
| 631 | } |
| 632 | |
| 633 | @Override |
| 634 | public Short decode(ByteBuffer byteSlice) { |
| 635 | return byteSlice.getShort(); |
| 636 | } |
Matthias Andreas Benkard | 261532a | 2021-12-12 20:09:27 +0100 | [diff] [blame] | 637 | } |
| 638 | |
Matthias Andreas Benkard | 3443018 | 2021-12-14 20:00:36 +0100 | [diff] [blame] | 639 | private static class IntegerDecoder extends Decoder<Integer> { |
Matthias Andreas Benkard | 261532a | 2021-12-12 20:09:27 +0100 | [diff] [blame] | 640 | |
Matthias Andreas Benkard | 3443018 | 2021-12-14 20:00:36 +0100 | [diff] [blame] | 641 | @Override |
| 642 | public byte alignment() { |
| 643 | return 4; |
| 644 | } |
Matthias Andreas Benkard | 261532a | 2021-12-12 20:09:27 +0100 | [diff] [blame] | 645 | |
Matthias Andreas Benkard | 3443018 | 2021-12-14 20:00:36 +0100 | [diff] [blame] | 646 | @Override |
| 647 | public Integer fixedSize() { |
| 648 | return 4; |
| 649 | } |
| 650 | |
| 651 | @Override |
| 652 | public Integer decode(ByteBuffer byteSlice) { |
| 653 | return byteSlice.getInt(); |
| 654 | } |
Matthias Andreas Benkard | 261532a | 2021-12-12 20:09:27 +0100 | [diff] [blame] | 655 | } |
| 656 | |
Matthias Andreas Benkard | 3443018 | 2021-12-14 20:00:36 +0100 | [diff] [blame] | 657 | private static class LongDecoder extends Decoder<Long> { |
Matthias Andreas Benkard | 261532a | 2021-12-12 20:09:27 +0100 | [diff] [blame] | 658 | |
Matthias Andreas Benkard | 3443018 | 2021-12-14 20:00:36 +0100 | [diff] [blame] | 659 | @Override |
| 660 | public byte alignment() { |
| 661 | return 8; |
| 662 | } |
Matthias Andreas Benkard | 261532a | 2021-12-12 20:09:27 +0100 | [diff] [blame] | 663 | |
Matthias Andreas Benkard | 3443018 | 2021-12-14 20:00:36 +0100 | [diff] [blame] | 664 | @Override |
| 665 | public Integer fixedSize() { |
| 666 | return 8; |
| 667 | } |
| 668 | |
| 669 | @Override |
| 670 | public Long decode(ByteBuffer byteSlice) { |
| 671 | return byteSlice.getLong(); |
| 672 | } |
Matthias Andreas Benkard | 261532a | 2021-12-12 20:09:27 +0100 | [diff] [blame] | 673 | } |
| 674 | |
Matthias Andreas Benkard | 3443018 | 2021-12-14 20:00:36 +0100 | [diff] [blame] | 675 | private static class DoubleDecoder extends Decoder<Double> { |
Matthias Andreas Benkard | 261532a | 2021-12-12 20:09:27 +0100 | [diff] [blame] | 676 | |
Matthias Andreas Benkard | 3443018 | 2021-12-14 20:00:36 +0100 | [diff] [blame] | 677 | @Override |
| 678 | public byte alignment() { |
| 679 | return 8; |
| 680 | } |
Matthias Andreas Benkard | 261532a | 2021-12-12 20:09:27 +0100 | [diff] [blame] | 681 | |
Matthias Andreas Benkard | 3443018 | 2021-12-14 20:00:36 +0100 | [diff] [blame] | 682 | @Override |
| 683 | public Integer fixedSize() { |
| 684 | return 8; |
| 685 | } |
| 686 | |
| 687 | @Override |
| 688 | public Double decode(ByteBuffer byteSlice) { |
| 689 | return byteSlice.getDouble(); |
| 690 | } |
Matthias Andreas Benkard | 261532a | 2021-12-12 20:09:27 +0100 | [diff] [blame] | 691 | } |
| 692 | |
Matthias Andreas Benkard | 3443018 | 2021-12-14 20:00:36 +0100 | [diff] [blame] | 693 | private static class StringDecoder extends Decoder<String> { |
Matthias Andreas Benkard | 261532a | 2021-12-12 20:09:27 +0100 | [diff] [blame] | 694 | |
Matthias Andreas Benkard | 3443018 | 2021-12-14 20:00:36 +0100 | [diff] [blame] | 695 | private final Charset charset; |
Matthias Andreas Benkard | 261532a | 2021-12-12 20:09:27 +0100 | [diff] [blame] | 696 | |
Matthias Andreas Benkard | 3443018 | 2021-12-14 20:00:36 +0100 | [diff] [blame] | 697 | public StringDecoder(Charset charset) { |
| 698 | this.charset = charset; |
| 699 | } |
| 700 | |
| 701 | @Override |
| 702 | public byte alignment() { |
| 703 | return 1; |
| 704 | } |
| 705 | |
| 706 | @Override |
| 707 | @Nullable |
| 708 | Integer fixedSize() { |
| 709 | return null; |
| 710 | } |
| 711 | |
| 712 | @Override |
| 713 | public String decode(ByteBuffer byteSlice) { |
| 714 | byteSlice.limit(byteSlice.limit() - 1); |
| 715 | return charset.decode(byteSlice).toString(); |
| 716 | } |
Matthias Andreas Benkard | 261532a | 2021-12-12 20:09:27 +0100 | [diff] [blame] | 717 | } |
| 718 | } |