Class JSONBuilder

java.lang.Object
net.sf.json.util.JSONBuilder
Direct Known Subclasses:
JSONStringer

public class JSONBuilder extends Object
JSONBuilder provides a quick and convenient way of producing JSON text. The texts produced strictly conform to JSON syntax rules. No whitespace is added, so the results are ready for transmission or storage. Each instance of JSONWriter can produce one JSON text.

A JSONBuilder instance provides a value method for appending values to the text, and a key method for adding keys before values in objects. There are array and endArray methods that make and bound array values, and object and endObject methods which make and bound object values. All of these methods return the JSONBuilder instance, permitting a cascade style. For example,

 new JSONBuilder(myWriter)
     .object()
         .key("JSON")
         .value("Hello, World!")
     .endObject();
which writes
 {"JSON":"Hello, World!"}
The first method called must be array or object. There are no methods for adding commas or colons. JSONBuilder adds them for you. Objects and arrays can be nested up to 20 levels deep. This can sometimes be easier than using a JSONObject to build a string.
Version:
1
  • Field Details

    • MAXDEPTH

      private static final int MAXDEPTH
      See Also:
    • comma

      private boolean comma
      The comma flag determines if a comma should be output before the next value.
    • mode

      protected char mode
      The current mode. Values: 'a' (array), 'd' (done), 'i' (initial), 'k' (key), 'o' (object).
    • stack

      private char[] stack
      The object/array stack.
    • top

      private int top
      The stack top index. A value of 0 indicates that the stack is empty.
    • writer

      protected Writer writer
      The writer that will receive the output.
  • Constructor Details

    • JSONBuilder

      public JSONBuilder(Writer w)
      Make a fresh JSONBuilder. It can be used to build one JSON text.
  • Method Details

    • append

      private JSONBuilder append(String s)
      Append a value.
      Parameters:
      s - A string value.
      Returns:
      this
      Throws:
      JSONException - If the value is out of sequence.
    • array

      public JSONBuilder array()
      Begin appending a new array. All values until the balancing endArray will be appended to this array. The endArray method must be called to mark the array's end.
      Returns:
      this
      Throws:
      JSONException - If the nesting is too deep, or if the object is started in the wrong place (for example as a key or after the end of the outermost array or object).
    • end

      private JSONBuilder end(char m, char c)
      End something.
      Parameters:
      m - Mode
      c - Closing character
      Returns:
      this
      Throws:
      JSONException - If unbalanced.
    • endArray

      public JSONBuilder endArray()
      End an array. This method most be called to balance calls to array.
      Returns:
      this
      Throws:
      JSONException - If incorrectly nested.
    • endObject

      public JSONBuilder endObject()
      End an object. This method most be called to balance calls to object.
      Returns:
      this
      Throws:
      JSONException - If incorrectly nested.
    • key

      public JSONBuilder key(String s)
      Append a key. The key will be associated with the next value. In an object, every value must be preceded by a key.
      Parameters:
      s - A key string.
      Returns:
      this
      Throws:
      JSONException - If the key is out of place. For example, keys do not belong in arrays or if the key is null.
    • object

      public JSONBuilder object()
      Begin appending a new object. All keys and values until the balancing endObject will be appended to this object. The endObject method must be called to mark the object's end.
      Returns:
      this
      Throws:
      JSONException - If the nesting is too deep, or if the object is started in the wrong place (for example as a key or after the end of the outermost array or object).
    • pop

      private void pop(char c)
      Pop an array or object scope.
      Parameters:
      c - The scope to close.
      Throws:
      JSONException - If nesting is wrong.
    • push

      private void push(char c)
      Push an array or object scope.
      Parameters:
      c - The scope to open.
      Throws:
      JSONException - If nesting is too deep.
    • value

      public JSONBuilder value(boolean b)
      Append either the value true or the value false.
      Parameters:
      b - A boolean.
      Returns:
      this
      Throws:
      JSONException
    • value

      public JSONBuilder value(double d)
      Append a double value.
      Parameters:
      d - A double.
      Returns:
      this
      Throws:
      JSONException - If the number is not finite.
    • value

      public JSONBuilder value(long l)
      Append a long value.
      Parameters:
      l - A long.
      Returns:
      this
      Throws:
      JSONException
    • value

      public JSONBuilder value(Object o)
      Append an object value.
      Parameters:
      o - The object to append. It can be null, or a Boolean, Number, String, JSONObject, or JSONArray, or an object with a toJSONString() method.
      Returns:
      this
      Throws:
      JSONException - If the value is out of sequence.