Class JSONWriter

java.lang.Object
com.codename1.io.JSONWriter
public final class JSONWriter extends java.lang.Object

Convenience JSON writer to complement JSONParser. Two access modes:

  1. One-shot: JSONWriter.toJson(map) / JSONWriter.toJson(map, writer) -- accepts a Map, List, String, Number, Boolean, null, and arbitrarily nested combinations.

  2. Fluent builder: JSONWriter.object().put("name", x).put("values", JSONWriter.array().add("a").add("b")).toJson() -- for ad-hoc request bodies where a Map literal would be noisier than the chain.

Encoded output is strict JSON: no trailing commas, all strings double-quoted with the standard backslash escapes for ", \, \n, \r, \t, and control chars < 0x20 emitted as \ + u00xx. No pretty-printing layer is included; if you need indented output, run the result through an external formatter at debug time.

For typed mapper-based serialization (DTOs annotated with @Mapped from the binding framework), use com.codename1.mapping.Mappers#toJson instead. JSONWriter is for ad-hoc and untyped payloads.

  • Nested Class Summary

    Nested Classes
    Modifier and Type
    Class
    Description
    static final class 
    JSONWriter.ArrayBuilder
    Fluent builder for [ ..., ..., ... ].
    static final class 
    JSONWriter.ObjectBuilder
    Fluent builder for { "k": v, ... }.

  • Method Summary

    Modifier and Type
    Method
    Description
    static JSONWriter.ArrayBuilder
    array()
    Starts a JSON-array builder.
    static JSONWriter.ObjectBuilder
    object()
    Starts a JSON-object builder.
    static String
    toJson(java.lang.Object value)
    Encodes value as JSON and returns the resulting string.
    static void
    toJson(java.lang.Object value, java.io.OutputStream out)
    Streams value as JSON into out using UTF-8 encoding.
    static void
    toJson(java.lang.Object value, java.io.Writer writer)
    Streams value as JSON into writer.

    Methods inherited from class java.lang.Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

  • Method Details

    • toJson

      public static String toJson(java.lang.Object value)
      Encodes value as JSON and returns the resulting string. Accepts Map, List, String, Number, Boolean, null. Maps with non-String keys are encoded using String.valueOf(key).

    • toJson

      public static void toJson(java.lang.Object value, java.io.Writer writer) throws java.io.IOException
      Streams value as JSON into writer. The writer is not closed or flushed by this method -- the caller owns the writer.
      Throws:
      java.io.IOException

    • toJson

      public static void toJson(java.lang.Object value, java.io.OutputStream out) throws java.io.IOException
      Streams value as JSON into out using UTF-8 encoding. The stream is flushed but not closed.
      Throws:
      java.io.IOException

    • object

      public static JSONWriter.ObjectBuilder object()
      Starts a JSON-object builder. Insertion order is preserved.

    • array

      public static JSONWriter.ArrayBuilder array()
      Starts a JSON-array builder.