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Android APIs
public class

JSONStringer

extends Object
java.lang.Object
   ↳ org.json.JSONStringer

Class Overview

Implements toString() and toString(). Most application developers should use those methods directly and disregard this API. For example:

 JSONObject object = ...
 String json = object.toString();

Stringers only encode well-formed JSON strings. In particular:

  • The stringer must have exactly one top-level array or object.
  • Lexical scopes must be balanced: every call to array() must have a matching call to endArray() and every call to object() must have a matching call to endObject().
  • Arrays may not contain keys (property names).
  • Objects must alternate keys (property names) and values.
  • Values are inserted with either literal value calls, or by nesting arrays or objects.
Calls that would result in a malformed JSON string will fail with a JSONException.

This class provides no facility for pretty-printing (ie. indenting) output. To encode indented output, use toString(int) or toString(int).

Some implementations of the API support at most 20 levels of nesting. Attempts to create more than 20 levels of nesting may fail with a JSONException.

Each stringer may be used to encode a single top level value. Instances of this class are not thread safe. Although this class is nonfinal, it was not designed for inheritance and should not be subclassed. In particular, self-use by overrideable methods is not specified. See Effective Java Item 17, "Design and Document or inheritance or else prohibit it" for further information.

Summary

Public Constructors
JSONStringer()
Public Methods
JSONStringer array()
Begins encoding a new array.
JSONStringer endArray()
Ends encoding the current array.
JSONStringer endObject()
Ends encoding the current object.
JSONStringer key(String name)
Encodes the key (property name) to this stringer.
JSONStringer object()
Begins encoding a new object.
String toString()
Returns the encoded JSON string.
JSONStringer value(double value)
Encodes value to this stringer.
JSONStringer value(long value)
Encodes value to this stringer.
JSONStringer value(boolean value)
Encodes value to this stringer.
JSONStringer value(Object value)
Encodes value.
[Expand]
Inherited Methods
From class java.lang.Object

Public Constructors

public JSONStringer ()

Since: API Level 1

Public Methods

public JSONStringer array ()

Since: API Level 1

Begins encoding a new array. Each call to this method must be paired with a call to endArray().

Returns
  • this stringer.
Throws
JSONException

public JSONStringer endArray ()

Since: API Level 1

Ends encoding the current array.

Returns
  • this stringer.
Throws
JSONException

public JSONStringer endObject ()

Since: API Level 1

Ends encoding the current object.

Returns
  • this stringer.
Throws
JSONException

public JSONStringer key (String name)

Since: API Level 1

Encodes the key (property name) to this stringer.

Parameters
name the name of the forthcoming value. May not be null.
Returns
  • this stringer.
Throws
JSONException

public JSONStringer object ()

Since: API Level 1

Begins encoding a new object. Each call to this method must be paired with a call to endObject().

Returns
  • this stringer.
Throws
JSONException

public String toString ()

Since: API Level 1

Returns the encoded JSON string.

If invoked with unterminated arrays or unclosed objects, this method's return value is undefined.

Warning: although it contradicts the general contract of toString(), this method returns null if the stringer contains no data.

Returns
  • a printable representation of this object.

public JSONStringer value (double value)

Since: API Level 1

Encodes value to this stringer.

Parameters
value a finite value. May not be NaNs or infinities.
Returns
  • this stringer.
Throws
JSONException

public JSONStringer value (long value)

Since: API Level 1

Encodes value to this stringer.

Returns
  • this stringer.
Throws
JSONException

public JSONStringer value (boolean value)

Since: API Level 1

Encodes value to this stringer.

Returns
  • this stringer.
Throws
JSONException

public JSONStringer value (Object value)

Since: API Level 1

Encodes value.

Parameters
value a JSONObject, JSONArray, String, Boolean, Integer, Long, Double or null. May not be NaNs or infinities.
Returns
  • this stringer.
Throws
JSONException