net.sf.json.util
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

Author:

JSON.org

Field Summary

protected char	mode The current mode.
protected Writer	writer The writer that will receive the output.

Constructor Summary

JSONBuilder(Writer w)
Make a fresh JSONBuilder.

Method Summary

JSONBuilder	array() Begin appending a new array.
JSONBuilder	endArray() End an array.
JSONBuilder	endObject() End an object.
JSONBuilder	key(String s) Append a key.
JSONBuilder	object() Begin appending a new object.
JSONBuilder	value(boolean b) Append either the value true or the value false.
JSONBuilder	value(double d) Append a double value.
JSONBuilder	value(long l) Append a long value.
JSONBuilder	value(Object o) Append an object value.

Methods inherited from class java.lang.Object

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

Field Detail

mode

protected char mode

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

writer

protected Writer writer

The writer that will receive the output.

Constructor Detail

JSONBuilder

public JSONBuilder(Writer w)

Make a fresh JSONBuilder. It can be used to build one JSON text.

Method Detail

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).

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).

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.