public class JSONObject extends Object
get
and opt
methods for accessing the values by name, and put
methods
for adding or replacing values by name. The values can be any of these types: Boolean
,
JSONArray
, JSONObject
, Number
, String
, or the
JSONObject.NULL
object. A JSONObject constructor can be used to convert an external form JSON text into
an internal form whose values can be retrieved with the get
and opt
methods, or to convert
values into a JSON text using the put
and toString
methods. A get
method
returns a value if one can be found, and throws an exception if one cannot be found. An opt
method
returns a default value instead of throwing an exception, and so is useful for obtaining optional values.
The generic get()
and opt()
methods return an object, which you can cast or query for type.
There are also typed get
and opt
methods that do type checking and type coersion for you.
The put
methods adds values to an object. For example,
myString = new JSONObject().put("JSON", "Hello, World!").toString();produces the string
{"JSON": "Hello, World"}
.
The texts produced by the toString
methods strictly conform to the JSON sysntax rules. The constructors
are more forgiving in the texts they will accept:
,
(comma) may appear just before the closing brace.'
(single quote).{ } [ ] / \ : , = ; #
and if they do not look like numbers and if they are not the reserved words
true
, false
, or null
.=
or =>
as well as by :
.;
(semicolon) as well as by ,
(comma).0-
(octal) or 0x-
(hex) prefix.Modifier and Type | Class and Description |
---|---|
static class |
JSONObject.Util |
Constructor and Description |
---|
JSONObject()
Construct an empty JSONObject.
|
Modifier and Type | Method and Description |
---|---|
JSONObject |
put(String key,
Object value)
Put a key/value pair in the JSONObject.
|
static Object |
stringToValue(String string)
Try to convert a string into a number, boolean, or null.
|
String |
toString()
Returns a string representation of the object.
|
public static Object stringToValue(String string)
string
- A String.public JSONObject put(String key, @Nullable Object value) throws JSONException
key
- A key string.value
- An object which is the value. It should be of one of these types: Boolean, Double, Integer, JSONArray,
JSONObject, Long, String, or the JSONObject.NULL object.JSONException
- If the value is non-finite number or if the key is null.@Nullable public String toString()
Object
toString
method returns a
string that "textually represents" this object. The result should be a concise but informative
representation that is easy for a person to read. It is recommended that all subclasses override
this method.
The toString
method for class Object
returns a string consisting of the name of
the class of which the object is an instance, the at-sign character `@
', and the unsigned
hexadecimal representation of the hash code of the object. In other words, this method returns a
string equal to the value of:
getClass().getName() + '@' + Integer.toHexString(hashCode())