| 1 | package be.nikiroo.utils.serial; |
| 2 | |
| 3 | import java.io.IOException; |
| 4 | import java.io.UnsupportedEncodingException; |
| 5 | import java.lang.reflect.Field; |
| 6 | import java.util.HashMap; |
| 7 | import java.util.Map; |
| 8 | |
| 9 | import be.nikiroo.utils.StringUtils; |
| 10 | |
| 11 | /** |
| 12 | * A simple class that can accept the output of {@link Exporter} to recreate |
| 13 | * objects as they were sent to said exporter. |
| 14 | * <p> |
| 15 | * This class requires the objects (and their potential enclosing objects) to |
| 16 | * have an empty constructor, and does not support inner classes (it does |
| 17 | * support nested classes, though). |
| 18 | * |
| 19 | * @author niki |
| 20 | */ |
| 21 | public class Importer { |
| 22 | static private Integer SIZE_ID = null; |
| 23 | static private byte[] NEWLINE = null; |
| 24 | |
| 25 | private Boolean link; |
| 26 | private Object me; |
| 27 | private Importer child; |
| 28 | private Map<String, Object> map; |
| 29 | |
| 30 | private String currentFieldName; |
| 31 | |
| 32 | static { |
| 33 | try { |
| 34 | SIZE_ID = "EXT:".getBytes("UTF-8").length; |
| 35 | NEWLINE = "\n".getBytes("UTF-8"); |
| 36 | } catch (UnsupportedEncodingException e) { |
| 37 | // UTF-8 is mandated to exist on confirming jre's |
| 38 | } |
| 39 | } |
| 40 | |
| 41 | /** |
| 42 | * Create a new {@link Importer}. |
| 43 | */ |
| 44 | public Importer() { |
| 45 | map = new HashMap<String, Object>(); |
| 46 | map.put("NULL", null); |
| 47 | } |
| 48 | |
| 49 | private Importer(Map<String, Object> map) { |
| 50 | this.map = map; |
| 51 | } |
| 52 | |
| 53 | /** |
| 54 | * Read some data into this {@link Importer}: it can be the full serialised |
| 55 | * content, or a number of lines of it (any given line <b>MUST</b> be |
| 56 | * complete though) and accumulate it with the already present data. |
| 57 | * |
| 58 | * @param data |
| 59 | * the data to parse |
| 60 | * |
| 61 | * @return itself so it can be chained |
| 62 | * |
| 63 | * @throws NoSuchFieldException |
| 64 | * if the serialised data contains information about a field |
| 65 | * which does actually not exist in the class we know of |
| 66 | * @throws NoSuchMethodException |
| 67 | * if a class described in the serialised data cannot be created |
| 68 | * because it is not compatible with this code |
| 69 | * @throws ClassNotFoundException |
| 70 | * if a class described in the serialised data cannot be found |
| 71 | * @throws IOException |
| 72 | * if the content cannot be read (for instance, corrupt data) |
| 73 | */ |
| 74 | public Importer read(String data) throws NoSuchFieldException, |
| 75 | NoSuchMethodException, ClassNotFoundException, IOException { |
| 76 | return read(data.getBytes("UTF-8"), 0); |
| 77 | } |
| 78 | |
| 79 | /** |
| 80 | * Read some data into this {@link Importer}: it can be the full serialised |
| 81 | * content, or a number of lines of it (any given line <b>MUST</b> be |
| 82 | * complete though) and accumulate it with the already present data. |
| 83 | * |
| 84 | * @param data |
| 85 | * the data to parse |
| 86 | * @param offset |
| 87 | * the offset at which to start reading the data (we ignore |
| 88 | * anything that goes before that offset) |
| 89 | * |
| 90 | * @return itself so it can be chained |
| 91 | * |
| 92 | * @throws NoSuchFieldException |
| 93 | * if the serialised data contains information about a field |
| 94 | * which does actually not exist in the class we know of |
| 95 | * @throws NoSuchMethodException |
| 96 | * if a class described in the serialised data cannot be created |
| 97 | * because it is not compatible with this code |
| 98 | * @throws ClassNotFoundException |
| 99 | * if a class described in the serialised data cannot be found |
| 100 | * @throws IOException |
| 101 | * if the content cannot be read (for instance, corrupt data) |
| 102 | */ |
| 103 | private Importer read(byte[] data, int offset) throws NoSuchFieldException, |
| 104 | NoSuchMethodException, ClassNotFoundException, IOException { |
| 105 | |
| 106 | int dataStart = offset; |
| 107 | while (dataStart < data.length) { |
| 108 | String id = ""; |
| 109 | if (data.length - dataStart >= SIZE_ID) { |
| 110 | id = new String(data, dataStart, SIZE_ID); |
| 111 | } |
| 112 | |
| 113 | boolean zip = id.equals("ZIP:"); |
| 114 | boolean b64 = id.equals("B64:"); |
| 115 | if (zip || b64) { |
| 116 | dataStart += SIZE_ID; |
| 117 | } |
| 118 | |
| 119 | int count = find(data, dataStart, NEWLINE); |
| 120 | count -= dataStart; |
| 121 | if (count < 0) { |
| 122 | count = data.length - dataStart; |
| 123 | } |
| 124 | |
| 125 | if (zip || b64) { |
| 126 | boolean unpacked = false; |
| 127 | try { |
| 128 | byte[] line = StringUtils.unbase64(data, dataStart, count, |
| 129 | zip); |
| 130 | unpacked = true; |
| 131 | read(line, 0); |
| 132 | } catch (IOException e) { |
| 133 | throw new IOException("Internal error when decoding " |
| 134 | + (unpacked ? "unpacked " : "") |
| 135 | + (zip ? "ZIP" : "B64") |
| 136 | + " content: input may be corrupt"); |
| 137 | } |
| 138 | } else { |
| 139 | String line = new String(data, dataStart, count, "UTF-8"); |
| 140 | processLine(line); |
| 141 | } |
| 142 | |
| 143 | dataStart += count + NEWLINE.length; |
| 144 | } |
| 145 | |
| 146 | return this; |
| 147 | } |
| 148 | |
| 149 | /** |
| 150 | * Read a single (whole) line of serialised data into this {@link Importer} |
| 151 | * and accumulate it with the already present data. |
| 152 | * |
| 153 | * @param line |
| 154 | * the line to parse |
| 155 | * |
| 156 | * @return TRUE if we are just done with one object or sub-object |
| 157 | * |
| 158 | * @throws NoSuchFieldException |
| 159 | * if the serialised data contains information about a field |
| 160 | * which does actually not exist in the class we know of |
| 161 | * @throws NoSuchMethodException |
| 162 | * if a class described in the serialised data cannot be created |
| 163 | * because it is not compatible with this code |
| 164 | * @throws ClassNotFoundException |
| 165 | * if a class described in the serialised data cannot be found |
| 166 | * @throws IOException |
| 167 | * if the content cannot be read (for instance, corrupt data) |
| 168 | */ |
| 169 | private boolean processLine(String line) throws NoSuchFieldException, |
| 170 | NoSuchMethodException, ClassNotFoundException, IOException { |
| 171 | // Defer to latest child if any |
| 172 | if (child != null) { |
| 173 | if (child.processLine(line)) { |
| 174 | if (currentFieldName != null) { |
| 175 | setField(currentFieldName, child.getValue()); |
| 176 | currentFieldName = null; |
| 177 | } |
| 178 | child = null; |
| 179 | } |
| 180 | |
| 181 | return false; |
| 182 | } |
| 183 | |
| 184 | if (line.equals("{")) { // START: new child if needed |
| 185 | if (link != null) { |
| 186 | child = new Importer(map); |
| 187 | } |
| 188 | } else if (line.equals("}")) { // STOP: report self to parent |
| 189 | return true; |
| 190 | } else if (line.startsWith("REF ")) { // REF: create/link self |
| 191 | String[] tab = line.substring("REF ".length()).split("@"); |
| 192 | String type = tab[0]; |
| 193 | tab = tab[1].split(":"); |
| 194 | String ref = tab[0]; |
| 195 | |
| 196 | link = map.containsKey(ref); |
| 197 | if (link) { |
| 198 | me = map.get(ref); |
| 199 | } else { |
| 200 | if (line.endsWith(":")) { |
| 201 | // construct |
| 202 | me = SerialUtils.createObject(type); |
| 203 | } else { |
| 204 | // direct value |
| 205 | int pos = line.indexOf(":"); |
| 206 | String encodedValue = line.substring(pos + 1); |
| 207 | me = SerialUtils.decode(encodedValue); |
| 208 | } |
| 209 | map.put(ref, me); |
| 210 | } |
| 211 | } else { // FIELD: new field *or* direct simple value |
| 212 | if (line.endsWith(":")) { |
| 213 | // field value is compound |
| 214 | currentFieldName = line.substring(0, line.length() - 1); |
| 215 | } else if (line.startsWith(":") || !line.contains(":") |
| 216 | || line.startsWith("\"") || CustomSerializer.isCustom(line)) { |
| 217 | // not a field value but a direct value |
| 218 | me = SerialUtils.decode(line); |
| 219 | } else { |
| 220 | // field value is direct |
| 221 | int pos = line.indexOf(":"); |
| 222 | String fieldName = line.substring(0, pos); |
| 223 | String encodedValue = line.substring(pos + 1); |
| 224 | Object value = null; |
| 225 | value = SerialUtils.decode(encodedValue); |
| 226 | |
| 227 | // To support simple types directly: |
| 228 | if (me == null) { |
| 229 | me = value; |
| 230 | } else { |
| 231 | setField(fieldName, value); |
| 232 | } |
| 233 | } |
| 234 | } |
| 235 | |
| 236 | return false; |
| 237 | } |
| 238 | |
| 239 | private void setField(String name, Object value) |
| 240 | throws NoSuchFieldException { |
| 241 | |
| 242 | try { |
| 243 | Field field = me.getClass().getDeclaredField(name); |
| 244 | |
| 245 | field.setAccessible(true); |
| 246 | field.set(me, value); |
| 247 | } catch (NoSuchFieldException e) { |
| 248 | throw new NoSuchFieldException(String.format( |
| 249 | "Field \"%s\" was not found in object of type \"%s\".", |
| 250 | name, me.getClass().getCanonicalName())); |
| 251 | } catch (Exception e) { |
| 252 | throw new NoSuchFieldException(String.format( |
| 253 | "Internal error when setting \"%s.%s\": %s", me.getClass() |
| 254 | .getCanonicalName(), name, e.getMessage())); |
| 255 | } |
| 256 | } |
| 257 | |
| 258 | /** |
| 259 | * Find the given needle in the data and return its position (or -1 if not |
| 260 | * found). |
| 261 | * |
| 262 | * @param data |
| 263 | * the data to look through |
| 264 | * @param offset |
| 265 | * the offset at wich to start searching |
| 266 | * @param needle |
| 267 | * the needle to find |
| 268 | * |
| 269 | * @return the position of the needle if found, -1 if not found |
| 270 | */ |
| 271 | private int find(byte[] data, int offset, byte[] needle) { |
| 272 | for (int i = offset; i + needle.length - 1 < data.length; i++) { |
| 273 | boolean same = true; |
| 274 | for (int j = 0; j < needle.length; j++) { |
| 275 | if (data[i + j] != needle[j]) { |
| 276 | same = false; |
| 277 | break; |
| 278 | } |
| 279 | } |
| 280 | |
| 281 | if (same) { |
| 282 | return i; |
| 283 | } |
| 284 | } |
| 285 | |
| 286 | return -1; |
| 287 | } |
| 288 | |
| 289 | /** |
| 290 | * Return the current deserialised value. |
| 291 | * |
| 292 | * @return the current value |
| 293 | */ |
| 294 | public Object getValue() { |
| 295 | return me; |
| 296 | } |
| 297 | } |