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078 * 079 * <jc>// Create a custom serializer for lax syntax using single quote characters</jc> 080 * JsonSerializer serializer = JsonSerializer.<jsm>create</jsm>().simple().sq().build(); 081 * 082 * <jc>// Clone an existing serializer and modify it to use single-quotes</jc> 083 * JsonSerializer serializer = JsonSerializer.<jsf>DEFAULT</jsf>.builder().sq().build(); 084 * 085 * <jc>// Serialize a POJO to JSON</jc> 086 * String json = serializer.serialize(someObject); 087 * </p> 088 */ 089public class JsonSerializer extends WriterSerializer { 090 091 //------------------------------------------------------------------------------------------------------------------- 092 // Configurable properties 093 //------------------------------------------------------------------------------------------------------------------- 094 095 private static final String PREFIX = "JsonSerializer."; 096 097 /** 098 * Configuration property: Add <js>"_type"</js> properties when needed. 099 * 100 * <h5 class='section'>Property:</h5> 101 * <ul> 102 * <li><b>Name:</b> <js>"JsonSerializer.addBeanTypes.b"</js> 103 * <li><b>Data type:</b> <code>Boolean</code> 104 * <li><b>Default:</b> <jk>false</jk> 105 * <li><b>Session property:</b> <jk>false</jk> 106 * <li><b>Methods:</b> 107 * <ul> 108 * <li class='jm'>{@link JsonSerializerBuilder#addBeanTypes(boolean)} 109 * </ul> 110 * </ul> 111 * 112 * <h5 class='section'>Description:</h5> 113 * <p> 114 * If <jk>true</jk>, then <js>"_type"</js> properties will be added to beans if their type cannot be inferred 115 * through reflection. 116 * 117 * <p> 118 * When present, this value overrides the {@link #SERIALIZER_addBeanTypes} setting and is 119 * provided to customize the behavior of specific serializers in a {@link SerializerGroup}. 120 */ 121 public static final String JSON_addBeanTypes = PREFIX + "addBeanTypes.b"; 122 123 /** 124 * Configuration property: Prefix solidus <js>'/'</js> characters with escapes. 125 * 126 * <h5 class='section'>Property:</h5> 127 * <ul> 128 * <li><b>Name:</b> <js>"JsonSerializer.escapeSolidus.b"</js> 129 * <li><b>Data type:</b> <code>Boolean</code> 130 * <li><b>Default:</b> <jk>false</jk> 131 * <li><b>Session property:</b> <jk>false</jk> 132 * <li><b>Methods:</b> 133 * <ul> 134 * <li class='jm'>{@link JsonSerializerBuilder#escapeSolidus(boolean)} 135 * <li class='jm'>{@link JsonSerializerBuilder#escapeSolidus()} 136 * </ul> 137 * </ul> 138 * 139 * <h5 class='section'>Description:</h5> 140 * <p> 141 * If <jk>true</jk>, solidus (e.g. slash) characters should be escaped. 142 * The JSON specification allows for either format. 143 * <br>However, if you're embedding JSON in an HTML script tag, this setting prevents confusion when trying to serialize 144 * <xt><\/script></xt>. 145 * 146 * <h5 class='section'>Example:</h5> 147 * <p class='bcode w800'> 148 * <jc>// Create a JSON serializer that escapes solidus characters.</jc> 149 * WriterSerializer s = JsonSerializer 150 * .<jsm>create</jsm>() 151 * .simple() 152 * .escapeSolidus() 153 * .build(); 154 * 155 * <jc>// Same, but use property.</jc> 156 * WriterSerializer s = JsonSerializer 157 * .<jsm>create</jsm>() 158 * .simple() 159 * .set(<jsf>JSON_escapeSolidus</jsf>, <jk>true</jk>) 160 * .build(); 161 * 162 * <jc>// Produces: "{foo:'<\/bar>'"</jc> 163 * String json = s.serialize(<jk>new</jk> ObjectMap().append(<js>"foo"</js>, <js>"</bar>"</js>); 164 * </p> 165 */ 166 public static final String JSON_escapeSolidus = PREFIX + "escapeSolidus.b"; 167 168 /** 169 * Configuration property: Simple JSON mode. 170 * 171 * <h5 class='section'>Property:</h5> 172 * <ul> 173 * <li><b>Name:</b> <js>"JsonSerializer.simpleMode.b"</js> 174 * <li><b>Data type:</b> <code>Boolean</code> 175 * <li><b>Default:</b> <jk>false</jk> 176 * <li><b>Session property:</b> <jk>false</jk> 177 * <li><b>Methods:</b> 178 * <ul> 179 * <li class='jm'>{@link JsonSerializerBuilder#simple(boolean)} 180 * <li class='jm'>{@link JsonSerializerBuilder#simple()} 181 * <li class='jm'>{@link JsonSerializerBuilder#ssq()} 182 * </ul> 183 * </ul> 184 * 185 * <h5 class='section'>Description:</h5> 186 * <p> 187 * If <jk>true</jk>, JSON attribute names will only be quoted when necessary. 188 * <br>Otherwise, they are always quoted. 189 * 190 * <p> 191 * Attributes do not need to be quoted when they conform to the following: 192 * <ol class='spaced-list'> 193 * <li>They start with an ASCII character or <js>'_'</js>. 194 * <li>They contain only ASCII characters or numbers or <js>'_'</js>. 195 * <li>They are not one of the following reserved words: 196 * <p class='bcode w800'> 197 * arguments, break, case, catch, class, const, continue, debugger, default, 198 * delete, do, else, enum, eval, export, extends, false, finally, for, function, 199 * if, implements, import, in, instanceof, interface, let, new, null, package, 200 * private, protected, public, return, static, super, switch, this, throw, 201 * true, try, typeof, var, void, while, with, undefined, yield 202 * </p> 203 * </ol> 204 * 205 * <h5 class='section'>Example:</h5> 206 * <p class='bcode w800'> 207 * <jc>// Create a JSON serializer in normal mode.</jc> 208 * WriterSerializer s1 = JsonSerializer 209 * .<jsm>create</jsm>() 210 * .build(); 211 * 212 * <jc>// Create a JSON serializer in simple mode.</jc> 213 * WriterSerializer s2 = JsonSerializer 214 * .<jsm>create</jsm>() 215 * .simple() 216 * .build(); 217 * 218 * ObjectMap m = <jk>new</jk> ObjectMap() 219 * .append(<js>"foo"</js>, <js>"x1"</js>) 220 * .append(<js>"_bar"</js>, <js>"x2"</js>) 221 * .append(<js>" baz "</js>, <js>"x3"</js>) 222 * .append(<js>"123"</js>, <js>"x4"</js>) 223 * .append(<js>"return"</js>, <js>"x5"</js>); 224 * .append(<js>""</js>, <js>"x6"</js>); 225 * 226 * <jc>// Produces:</jc> 227 * <jc>// {</jc> 228 * <jc>// "foo": "x1"</jc> 229 * <jc>// "_bar": "x2"</jc> 230 * <jc>// " baz ": "x3"</jc> 231 * <jc>// "123": "x4"</jc> 232 * <jc>// "return": "x5"</jc> 233 * <jc>// "": "x6"</jc> 234 * <jc>// }</jc> 235 * String json1 = s1.serialize(m); 236 * 237 * <jc>// Produces:</jc> 238 * <jc>// {</jc> 239 * <jc>// foo: "x1"</jc> 240 * <jc>// _bar: "x2"</jc> 241 * <jc>// " baz ": "x3"</jc> 242 * <jc>// "123": "x4"</jc> 243 * <jc>// "return": "x5"</jc> 244 * <jc>// "": "x6"</jc> 245 * <jc>// }</jc> 246 * String json2 = s2.serialize(m); 247 * </p> 248 */ 249 public static final String JSON_simpleMode = PREFIX + "simpleMode.b"; 250 251 //------------------------------------------------------------------------------------------------------------------- 252 // Predefined instances 253 //------------------------------------------------------------------------------------------------------------------- 254 255 /** Default serializer, all default settings.*/ 256 public static final JsonSerializer DEFAULT = new JsonSerializer(PropertyStore.DEFAULT); 257 258 /** Default serializer, all default settings.*/ 259 public static final JsonSerializer DEFAULT_READABLE = new Readable(PropertyStore.DEFAULT); 260 261 262 //------------------------------------------------------------------------------------------------------------------- 263 // Predefined subclasses 264 //------------------------------------------------------------------------------------------------------------------- 265 266 /** Default serializer, with whitespace. */ 267 public static class Readable extends JsonSerializer { 268 269 /** 270 * Constructor. 271 * 272 * @param ps The property store containing all the settings for this object. 273 */ 274 public Readable(PropertyStore ps) { 275 super( 276 ps.builder().set(SERIALIZER_useWhitespace, true).build() 277 ); 278 } 279 } 280 281 /** 282 * Default serializer, single quotes, simple mode, with whitespace and recursion detection. 283 * Note that recursion detection introduces a small performance penalty. 284 */ 285 public static class ReadableSafe extends JsonSerializer { 286 287 /** 288 * Constructor. 289 * 290 * @param ps The property store containing all the settings for this object. 291 */ 292 public ReadableSafe(PropertyStore ps) { 293 super( 294 ps.builder() 295 .set(JSON_simpleMode, true) 296 .set(WSERIALIZER_quoteChar, '\'') 297 .set(SERIALIZER_useWhitespace, true) 298 .set(BEANTRAVERSE_detectRecursions, true) 299 .build() 300 ); 301 } 302 } 303 304 305 //------------------------------------------------------------------------------------------------------------------- 306 // Instance 307 //------------------------------------------------------------------------------------------------------------------- 308 309 private final boolean 310 simpleMode, 311 escapeSolidus, 312 addBeanTypes; 313 314 private volatile JsonSchemaSerializer schemaSerializer; 315 316 /** 317 * Constructor. 318 * 319 * @param ps 320 * The property store containing all the settings for this object. 321 */ 322 public JsonSerializer(PropertyStore ps) { 323 this(ps, "application/json", "application/json,text/json"); 324 } 325 326 /** 327 * Constructor. 328 * 329 * @param ps 330 * The property store containing all the settings for this object. 331 * @param produces 332 * The media type that this serializer produces. 333 * @param accept 334 * The accept media types that the serializer can handle. 335 * <p> 336 * Can contain meta-characters per the <code>media-type</code> specification of {@doc RFC2616.section14.1} 337 * <p> 338 * If empty, then assumes the only media type supported is <code>produces</code>. 339 * <p> 340 * For example, if this serializer produces <js>"application/json"</js> but should handle media types of 341 * <js>"application/json"</js> and <js>"text/json"</js>, then the arguments should be: 342 * <p class='bcode w800'> 343 * <jk>super</jk>(ps, <js>"application/json"</js>, <js>"application/json,text/json"</js>); 344 * </p> 345 * <br>...or... 346 * <p class='bcode w800'> 347 * <jk>super</jk>(ps, <js>"application/json"</js>, <js>"*​/json"</js>); 348 * </p> 349 * <p> 350 * The accept value can also contain q-values. 351 */ 352 public JsonSerializer(PropertyStore ps, String produces, String accept) { 353 super(ps, produces, accept); 354 355 simpleMode = getBooleanProperty(JSON_simpleMode, false); 356 escapeSolidus = getBooleanProperty(JSON_escapeSolidus, false); 357 addBeanTypes = getBooleanProperty(JSON_addBeanTypes, getBooleanProperty(SERIALIZER_addBeanTypes, false)); 358 } 359 360 @Override /* Context */ 361 public JsonSerializerBuilder builder() { 362 return new JsonSerializerBuilder(getPropertyStore()); 363 } 364 365 /** 366 * Instantiates a new clean-slate {@link JsonSerializerBuilder} object. 367 * 368 * <p> 369 * This is equivalent to simply calling <code><jk>new</jk> JsonSerializerBuilder()</code>. 370 * 371 * @return A new {@link JsonSerializerBuilder} object. 372 */ 373 public static JsonSerializerBuilder create() { 374 return new JsonSerializerBuilder(); 375 } 376 377 /** 378 * Returns the schema serializer based on the settings of this serializer. 379 * 380 * <p> 381 * Note that this method creates a builder initialized to all default settings, whereas {@link #builder()} copies 382 * the settings of the object called on. 383 * 384 * @return The schema serializer. 385 */ 386 public JsonSchemaSerializer getSchemaSerializer() { 387 if (schemaSerializer == null) 388 schemaSerializer = builder().build(JsonSchemaSerializer.class); 389 return schemaSerializer; 390 } 391 392 //----------------------------------------------------------------------------------------------------------------- 393 // Entry point methods 394 //----------------------------------------------------------------------------------------------------------------- 395 396 @Override /* Serializer */ 397 public JsonSerializerSession createSession(SerializerSessionArgs args) { 398 return new JsonSerializerSession(this, args); 399 } 400 401 //----------------------------------------------------------------------------------------------------------------- 402 // Properties 403 //----------------------------------------------------------------------------------------------------------------- 404 405 /** 406 * Configuration property: Simple JSON mode. 407 * 408 * @see #JSON_simpleMode 409 * @return 410 * <jk>true</jk> if JSON attribute names will only be quoted when necessary. 411 * <br>Otherwise, they are always quoted. 412 */ 413 protected final boolean isSimpleMode() { 414 return simpleMode; 415 } 416 417 /** 418 * Configuration property: Prefix solidus <js>'/'</js> characters with escapes. 419 * 420 * @see #JSON_escapeSolidus 421 * @return 422 * <jk>true</jk> if solidus (e.g. slash) characters should be escaped. 423 */ 424 protected final boolean isEscapeSolidus() { 425 return escapeSolidus; 426 } 427 428 /** 429 * Configuration property: Add <js>"_type"</js> properties when needed. 430 * 431 * @see #JSON_addBeanTypes 432 * @return 433 * <jk>true</jk> if <js>"_type"</js> properties will be added to beans if their type cannot be inferred 434 * through reflection. 435 */ 436 @Override 437 protected final boolean isAddBeanTypes() { 438 return addBeanTypes; 439 } 440 441 @Override /* Context */ 442 public ObjectMap asMap() { 443 return super.asMap() 444 .append("JsonSerializer", new ObjectMap() 445 .append("simpleMode", simpleMode) 446 .append("escapeSolidus", escapeSolidus) 447 .append("addBeanTypes", addBeanTypes) 448 ); 449 } 450}