001// ***************************************************************************************************************************
002// * Licensed to the Apache Software Foundation (ASF) under one or more contributor license agreements.  See the NOTICE file *
003// * distributed with this work for additional information regarding copyright ownership.  The ASF licenses this file        *
004// * to you under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance            *
005// * with the License.  You may obtain a copy of the License at                                                              *
006// *                                                                                                                         *
007// *  http://www.apache.org/licenses/LICENSE-2.0                                                                             *
008// *                                                                                                                         *
009// * Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an  *
010// * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the License for the        *
011// * specific language governing permissions and limitations under the License.                                              *
012// ***************************************************************************************************************************
013package org.apache.juneau.dto.jsonschema;
014
015/**
016 * Represents possible JSON types in the JSON-Schema core specification.
017 *
018 * <p>
019 * Implements custom <code>toString()</code> and <code>fromString(String)</code> methods that override the default
020 * serialization/parsing behavior of <code>Enum</code> types so that they are represented in lowercase form (as per the
021 * specification).
022 *
023 * <h5 class='section'>Example:</h5>
024 * <p class='bcode w800'>
025 *    // Produces 'number', not 'NUMBER'.
026 *    String json = JsonSerializer.DEFAULT.serialize(JsonType.NUMBER);
027 * </p>
028 *
029 * <h5 class='section'>See Also:</h5>
030 * <ul class='doctree'>
031 *    <li class='jp'>{@doc package-summary.html#TOC org.apache.juneau.dto.jsonschema}
032 * </ul>
033 */
034public enum JsonType {
035
036   /** array */
037   ARRAY("array"),
038
039   /** boolean */
040   BOOLEAN("boolean"),
041
042   /** integer */
043   INTEGER("integer"),
044
045   /** null */
046   NULL("null"),
047
048   /** number */
049   NUMBER("number"),
050
051   /** object */
052   OBJECT("object"),
053
054   /** string */
055   STRING("string"),
056
057   /** any */
058   ANY("any");
059
060   private final String value;   // The serialized format of the enum.
061
062   private JsonType(String value) {
063      this.value = value;
064   }
065
066   /**
067    * Returns the lowercase form of this enum that's compatible with the JSON-Schema specification.
068    */
069   @Override /* Object */
070   public String toString() {
071      return value;
072   }
073
074   /**
075    * Converts the specified lowercase form of the enum back into an <code>Enum</code>.
076    *
077    * @param value The lowercase form of the enum (e.g. <js>"array"</js>).
078    * @return The matching <code>Enum</code>, or <jk>null</jk> if no match found.
079    */
080   public static JsonType fromString(String value) {
081      if (value == null || value.length() < 4)
082         return null;
083      char c = value.charAt(0);
084      if (c == 'a') {
085         if (value.equals("array"))
086         return ARRAY;
087         if (value.equals("any"))
088            return ANY;
089      }
090      if (c == 'b' && value.equals("boolean"))
091         return BOOLEAN;
092      if (c == 'i' && value.equals("integer"))
093         return INTEGER;
094      if (c == 'n') {
095         c = value.charAt(2);
096         if (c == 'l' && value.equals("null"))
097            return NULL;
098         if (c == 'm' && value.equals("number"))
099            return NUMBER;
100         return null;
101      }
102      if (c == 'o' && value.equals("object"))
103         return OBJECT;
104      if (c == 's' && value.equals("string"))
105         return STRING;
106      return null;
107   }
108}