| 1 | package be.nikiroo.utils.serial; |
| 2 | |
| 3 | import java.lang.reflect.Constructor; |
| 4 | import java.lang.reflect.Field; |
| 5 | import java.lang.reflect.InvocationTargetException; |
| 6 | import java.io.NotSerializableException; |
| 7 | import java.lang.reflect.Field; |
| 8 | import java.util.HashMap; |
| 9 | import java.util.Map; |
| 10 | |
| 11 | /** |
| 12 | * Small class to help serialise/deserialise objects. |
| 13 | * <p> |
| 14 | * Note that we do not support inner classes (but we do support nested classes) |
| 15 | * and all objects require an empty constructor to be deserialised. |
| 16 | * |
| 17 | * @author niki |
| 18 | */ |
| 19 | public class SerialUtils { |
| 20 | private static Map<String, CustomSerializer> customTypes; |
| 21 | |
| 22 | static { |
| 23 | customTypes = new HashMap<String, CustomSerializer>(); |
| 24 | // TODO: add "default" custom serialisers |
| 25 | } |
| 26 | |
| 27 | /** |
| 28 | * Create an empty object of the given type. |
| 29 | * |
| 30 | * @param type |
| 31 | * the object type (its class name) |
| 32 | * |
| 33 | * @return the new object |
| 34 | * |
| 35 | * @throws NoSuchMethodException if the given class is not compatible with this code |
| 36 | * @throws ClassNotFoundException if the class cannot be found or created |
| 37 | */ |
| 38 | public static Object createObject(String type) throws NoSuchMethodException, |
| 39 | ClassNotFoundException { |
| 40 | |
| 41 | try { |
| 42 | Class<?> clazz = getClass(type); |
| 43 | if (clazz == null) { |
| 44 | throw new ClassNotFoundException("Class not found: " + type); |
| 45 | } |
| 46 | |
| 47 | String className = clazz.getName(); |
| 48 | Object[] args = null; |
| 49 | Constructor<?> ctor = null; |
| 50 | if (className.contains("$")) { |
| 51 | Object javaParent = createObject(className.substring(0, |
| 52 | className.lastIndexOf('$'))); |
| 53 | args = new Object[] { javaParent }; |
| 54 | ctor = clazz.getDeclaredConstructor(new Class[] { javaParent |
| 55 | .getClass() }); |
| 56 | } else { |
| 57 | args = new Object[] {}; |
| 58 | ctor = clazz.getDeclaredConstructor(); |
| 59 | } |
| 60 | |
| 61 | ctor.setAccessible(true); |
| 62 | return ctor.newInstance(args); |
| 63 | } catch (NoSuchMethodException e) { |
| 64 | throw new NoSuchMethodException( |
| 65 | String.format( |
| 66 | "Objects of type \"%s\" cannot be created by this code: maybe the class" |
| 67 | + " or its enclosing class doesn't have an empty constructor?", |
| 68 | type)); |
| 69 | |
| 70 | } |
| 71 | catch (SecurityException e) { throw new ClassNotFoundException("Cannot instantiate: " + type, e); } |
| 72 | catch (InstantiationException e) { throw new ClassNotFoundException("Cannot instantiate: " + type, e); } |
| 73 | catch (IllegalAccessException e) { throw new ClassNotFoundException("Cannot instantiate: " + type, e); } |
| 74 | catch (IllegalArgumentException e) { throw new ClassNotFoundException("Cannot instantiate: " + type, e); } |
| 75 | catch (InvocationTargetException e) { throw new ClassNotFoundException("Cannot instantiate: " + type, e); } |
| 76 | } |
| 77 | |
| 78 | static public void addCustomSerializer(CustomSerializer serializer) { |
| 79 | customTypes.put(serializer.getType(), serializer); |
| 80 | } |
| 81 | |
| 82 | static void append(StringBuilder builder, Object o, Map<Integer, Object> map) |
| 83 | throws NotSerializableException { |
| 84 | |
| 85 | Field[] fields = new Field[] {}; |
| 86 | String type = ""; |
| 87 | String id = "NULL"; |
| 88 | |
| 89 | if (o != null) { |
| 90 | int hash = System.identityHashCode(o); |
| 91 | fields = o.getClass().getDeclaredFields(); |
| 92 | type = o.getClass().getCanonicalName(); |
| 93 | if (type == null) { |
| 94 | throw new NotSerializableException( |
| 95 | String.format( |
| 96 | "Cannot find the class for this object: %s (it could be an inner class, which is not supported)", |
| 97 | o)); |
| 98 | } |
| 99 | id = Integer.toString(hash); |
| 100 | if (map.containsKey(hash)) { |
| 101 | fields = new Field[] {}; |
| 102 | } else { |
| 103 | map.put(hash, o); |
| 104 | } |
| 105 | } |
| 106 | |
| 107 | builder.append("{\nREF ").append(type).append("@").append(id); |
| 108 | try { |
| 109 | for (Field field : fields) { |
| 110 | field.setAccessible(true); |
| 111 | |
| 112 | if (field.getName().startsWith("this$")) { |
| 113 | // Do not keep this links of nested classes |
| 114 | continue; |
| 115 | } |
| 116 | |
| 117 | builder.append("\n"); |
| 118 | builder.append(field.getName()); |
| 119 | builder.append(":"); |
| 120 | Object value; |
| 121 | |
| 122 | value = field.get(o); |
| 123 | |
| 124 | if (!encode(builder, value)) { |
| 125 | builder.append("\n"); |
| 126 | append(builder, value, map); |
| 127 | } |
| 128 | } |
| 129 | } catch (IllegalArgumentException e) { |
| 130 | e.printStackTrace(); // should not happen (see setAccessible) |
| 131 | } catch (IllegalAccessException e) { |
| 132 | e.printStackTrace(); // should not happen (see setAccessible) |
| 133 | } |
| 134 | builder.append("\n}"); |
| 135 | } |
| 136 | |
| 137 | // return true if encoded (supported) |
| 138 | static boolean encode(StringBuilder builder, Object value) { |
| 139 | if (value == null) { |
| 140 | builder.append("NULL"); |
| 141 | } else if (customTypes.containsKey(value.getClass().getCanonicalName())) { |
| 142 | customTypes.get(value.getClass().getCanonicalName())// |
| 143 | .encode(builder, value); |
| 144 | } else if (value instanceof String) { |
| 145 | encodeString(builder, (String) value); |
| 146 | } else if (value instanceof Boolean) { |
| 147 | builder.append(value); |
| 148 | } else if (value instanceof Byte) { |
| 149 | builder.append(value).append('b'); |
| 150 | } else if (value instanceof Character) { |
| 151 | encodeString(builder, (String) value); |
| 152 | builder.append('c'); |
| 153 | } else if (value instanceof Short) { |
| 154 | builder.append(value).append('s'); |
| 155 | } else if (value instanceof Integer) { |
| 156 | builder.append(value); |
| 157 | } else if (value instanceof Long) { |
| 158 | builder.append(value).append('L'); |
| 159 | } else if (value instanceof Float) { |
| 160 | builder.append(value).append('F'); |
| 161 | } else if (value instanceof Double) { |
| 162 | builder.append(value).append('d'); |
| 163 | } else { |
| 164 | return false; |
| 165 | } |
| 166 | |
| 167 | return true; |
| 168 | } |
| 169 | |
| 170 | static Object decode(String encodedValue) { |
| 171 | String cut = ""; |
| 172 | if (encodedValue.length() > 1) { |
| 173 | cut = encodedValue.substring(0, encodedValue.length() - 1); |
| 174 | } |
| 175 | |
| 176 | if (CustomSerializer.isCustom(encodedValue)) { |
| 177 | // custom:TYPE_NAME:"content is String-encoded" |
| 178 | String type = CustomSerializer.typeOf(encodedValue); |
| 179 | if (customTypes.containsKey(type)) { |
| 180 | return customTypes.get(type).decode(encodedValue); |
| 181 | } else { |
| 182 | throw new java.util.UnknownFormatConversionException( |
| 183 | "Unknown custom type: " + type); |
| 184 | } |
| 185 | } else if (encodedValue.equals("NULL") || encodedValue.equals("null")) { |
| 186 | return null; |
| 187 | } else if (encodedValue.endsWith("\"")) { |
| 188 | return decodeString(encodedValue); |
| 189 | } else if (encodedValue.equals("true")) { |
| 190 | return true; |
| 191 | } else if (encodedValue.equals("false")) { |
| 192 | return false; |
| 193 | } else if (encodedValue.endsWith("b")) { |
| 194 | return Byte.parseByte(cut); |
| 195 | } else if (encodedValue.endsWith("c")) { |
| 196 | return decodeString(cut).charAt(0); |
| 197 | } else if (encodedValue.endsWith("s")) { |
| 198 | return Short.parseShort(cut); |
| 199 | } else if (encodedValue.endsWith("L")) { |
| 200 | return Long.parseLong(cut); |
| 201 | } else if (encodedValue.endsWith("F")) { |
| 202 | return Float.parseFloat(cut); |
| 203 | } else if (encodedValue.endsWith("d")) { |
| 204 | return Double.parseDouble(cut); |
| 205 | } else { |
| 206 | return Integer.parseInt(encodedValue); |
| 207 | } |
| 208 | } |
| 209 | |
| 210 | static private Class<?> getClass(String type) throws ClassNotFoundException, |
| 211 | NoSuchMethodException { |
| 212 | Class<?> clazz = null; |
| 213 | try { |
| 214 | clazz = Class.forName(type); |
| 215 | } catch (ClassNotFoundException e) { |
| 216 | int pos = type.length(); |
| 217 | pos = type.lastIndexOf(".", pos); |
| 218 | if (pos >= 0) { |
| 219 | String parentType = type.substring(0, pos); |
| 220 | String nestedType = type.substring(pos + 1); |
| 221 | Class<?> javaParent = null; |
| 222 | try { |
| 223 | javaParent = getClass(parentType); |
| 224 | parentType = javaParent.getName(); |
| 225 | clazz = Class.forName(parentType + "$" + nestedType); |
| 226 | } catch (Exception ee) { |
| 227 | } |
| 228 | |
| 229 | if (javaParent == null) { |
| 230 | throw new NoSuchMethodException( |
| 231 | "Class not found: " |
| 232 | + type |
| 233 | + " (the enclosing class cannot be created: maybe it doesn't have an empty constructor?)"); |
| 234 | } |
| 235 | } |
| 236 | } |
| 237 | |
| 238 | return clazz; |
| 239 | } |
| 240 | |
| 241 | // aa bb -> "aa\tbb" |
| 242 | private static void encodeString(StringBuilder builder, String raw) { |
| 243 | builder.append('\"'); |
| 244 | for (char car : raw.toCharArray()) { |
| 245 | switch (car) { |
| 246 | case '\\': |
| 247 | builder.append("\\\\"); |
| 248 | break; |
| 249 | case '\r': |
| 250 | builder.append("\\r"); |
| 251 | break; |
| 252 | case '\n': |
| 253 | builder.append("\\n"); |
| 254 | break; |
| 255 | case '"': |
| 256 | builder.append("\\\""); |
| 257 | break; |
| 258 | default: |
| 259 | builder.append(car); |
| 260 | break; |
| 261 | } |
| 262 | } |
| 263 | builder.append('\"'); |
| 264 | } |
| 265 | |
| 266 | // "aa\tbb" -> aa bb |
| 267 | private static String decodeString(String escaped) { |
| 268 | StringBuilder builder = new StringBuilder(); |
| 269 | |
| 270 | boolean escaping = false; |
| 271 | for (char car : escaped.toCharArray()) { |
| 272 | if (!escaping) { |
| 273 | if (car == '\\') { |
| 274 | escaping = true; |
| 275 | } else { |
| 276 | builder.append(car); |
| 277 | } |
| 278 | } else { |
| 279 | switch (car) { |
| 280 | case '\\': |
| 281 | builder.append('\\'); |
| 282 | break; |
| 283 | case 'r': |
| 284 | builder.append('\r'); |
| 285 | break; |
| 286 | case 'n': |
| 287 | builder.append('\n'); |
| 288 | break; |
| 289 | case '"': |
| 290 | builder.append('"'); |
| 291 | break; |
| 292 | } |
| 293 | escaping = false; |
| 294 | } |
| 295 | } |
| 296 | |
| 297 | return builder.substring(1, builder.length() - 1).toString(); |
| 298 | } |
| 299 | } |