Package rife.json

Class Json

java.lang.Object
rife.json.Json
public final class Json extends Object
Provides JSON parsing, generation and bean conversion.

Parsing is strict according to RFC 8259 and produces plain Java values: JsonObject, JsonArray, String, Long, Double, Boolean and null. Integral numbers that don't fit a Long become Double values and can lose precision. When an object contains the same member name multiple times, the last value wins.

For instance: 

 var config = Json.parseObject("""
     {"name": "my-app", "port": 8080}""");
 var port = config.getInt("port", 80);

Beans convert in both directions with from(java.lang.Object) and toBean(rife.json.JsonObject, java.lang.Class<T>), relying on the same property conventions as the rest of RIFE2. Records convert through their components in the same fashion.

Since:
1.10

  • Method Details

    • parse

      public static Object parse(String json)
      Parses a JSON document.
      Parameters:
      json - the JSON document to parse
      Returns:
      the parsed value: a JsonObject, JsonArray, String, Long, Double, Boolean or null
      Throws:
      JsonParseException - when the document couldn't be parsed
      Since:
      1.10

    • parse

      public static Object parse(Reader reader) throws IOException
      Parses a JSON document from a reader.

      The reader is read fully before parsing starts.

      Parameters:
      reader - the reader to parse the JSON document from
      Returns:
      the parsed value
      Throws:
      JsonParseException - when the document couldn't be parsed
      IOException - when an error occurred while reading
      Since:
      1.10

    • parseObject

      public static JsonObject parseObject(String json)
      Parses a JSON document that is expected to be a JSON object.
      Parameters:
      json - the JSON document to parse
      Returns:
      the parsed JsonObject
      Throws:
      JsonParseException - when the document couldn't be parsed or isn't a JSON object
      Since:
      1.10

    • parseObject

      public static JsonObject parseObject(Reader reader) throws IOException
      Parses a JSON document from a reader that is expected to be a JSON object.
      Parameters:
      reader - the reader to parse the JSON document from
      Returns:
      the parsed JsonObject
      Throws:
      JsonParseException - when the document couldn't be parsed or isn't a JSON object
      IOException - when an error occurred while reading
      Since:
      1.10

    • parseArray

      public static JsonArray parseArray(String json)
      Parses a JSON document that is expected to be a JSON array.
      Parameters:
      json - the JSON document to parse
      Returns:
      the parsed JsonArray
      Throws:
      JsonParseException - when the document couldn't be parsed or isn't a JSON array
      Since:
      1.10

    • parseArray

      public static JsonArray parseArray(Reader reader) throws IOException
      Parses a JSON document from a reader that is expected to be a JSON array.
      Parameters:
      reader - the reader to parse the JSON document from
      Returns:
      the parsed JsonArray
      Throws:
      JsonParseException - when the document couldn't be parsed or isn't a JSON array
      IOException - when an error occurred while reading
      Since:
      1.10

    • from

      public static JsonObject from(Object bean)
      Creates a JSON object from the properties of a bean.

      Properties that are constrained as not serialized are not included. Records are converted through their components instead of properties.

      Parameters:
      bean - the bean to convert
      Returns:
      the JSON object with the bean's properties as members
      Since:
      1.10

    • fromExcluded

      public static JsonObject fromExcluded(Object bean, String... excludedProperties)
      Creates a JSON object from the properties of a bean, excluding particular properties.
      Parameters:
      bean - the bean to convert
      excludedProperties - the names of the properties to exclude
      Returns:
      the JSON object with the bean's properties as members
      Since:
      1.10

    • from

      public static JsonArray from(Collection<?> elements)
      Creates a JSON array from the elements of a collection, converting beans and records to JSON objects like from(Object) does.
      Parameters:
      elements - the collection to convert
      Returns:
      the JSON array with the converted elements
      Since:
      1.10

    • toString

      public static String toString(Object value)
      Serializes any JSON value into its compact string representation.

      Accepts the same values as JSON object members and JSON array elements: strings, numbers, booleans, null, maps, collections, arrays, dates, temporals, enums, JsonObject and JsonArray. Use from(java.lang.Object) to convert beans first.

      Parameters:
      value - the value to serialize
      Returns:
      the JSON string
      Since:
      1.10

    • toPrettyString

      public static String toPrettyString(Object value)
      Serializes any JSON value into its multi-line indented string representation.

      Accepts the same values as toString(Object).

      Parameters:
      value - the value to serialize
      Returns:
      the pretty-printed JSON string
      Since:
      1.10

    • toBean

      public static <T> T toBean(JsonObject json, Class<T> beanClass)
      Fills a new bean instance with the members of a JSON object.

      Members without a matching bean property are ignored. Nested JSON objects are converted to the types of their matching bean properties. The elements of arrays, collections and maps are converted to the component and generic types that the property setters declare.

      Properties that are constrained as not serialized or not editable are never filled in.

      Records are instantiated through their canonical constructor with the members that match their components, absent members become null or the primitive default values.

      Parameters:
      json - the JSON object with the values to fill in
      beanClass - the class of the bean to fill
      Returns:
      the filled bean instance
      Since:
      1.10

    • toBeanList

      public static <T> List<T> toBeanList(JsonArray json, Class<T> beanClass)
      Fills a list of new bean instances with the members of the JSON objects in a JSON array.

      Each element is converted with the same rules as toBean(rife.json.JsonObject, java.lang.Class<T>), null elements stay null.

      Parameters:
      json - the JSON array with the JSON objects to convert
      beanClass - the class of the beans to fill
      Returns:
      the list with a bean instance for each element
      Since:
      1.10