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Summary: Fields | Ctors | Methods | Inherited Methods | [Expand All]

Added in API level 1

public class

JSONObject

extends Object

java.lang.Object
↳	org.json.JSONObject

Class Overview

A modifiable set of name/value mappings. Names are unique, non-null strings. Values may be any mix of JSONObjects , JSONArrays , Strings, Booleans, Integers, Longs, Doubles or NULL . Values may not be null , NaNs , infinities , or of any type not listed here.

This class can coerce values to another type when requested.

When the requested type is a boolean, strings will be coerced using a case-insensitive comparison to "true" and "false".
When the requested type is a double, other Number types will be coerced using doubleValue . Strings that can be coerced using valueOf(String) will be.
When the requested type is an int, other Number types will be coerced using intValue . Strings that can be coerced using valueOf(String) will be, and then cast to int.
When the requested type is a long, other Number types will be coerced using longValue . Strings that can be coerced using valueOf(String) will be, and then cast to long. This two-step conversion is lossy for very large values. For example, the string "9223372036854775806" yields the long 9223372036854775807.
When the requested type is a String, other non-null values will be coerced using valueOf(Object) . Although null cannot be coerced, the sentinel value NULL is coerced to the string "null".

This class can look up both mandatory and optional values:

Use get Type () to retrieve a mandatory value. This fails with a JSONException if the requested name has no value or if the value cannot be coerced to the requested type.
Use opt Type () to retrieve an optional value. This returns a system- or user-supplied default if the requested name has no value or if the value cannot be coerced to the requested type.

Warning: this class represents null in two incompatible ways: the standard Java null reference, and the sentinel value NULL . In particular, calling put(name, null) removes the named entry from the object but put(name, JSONObject.NULL) stores an entry whose value is JSONObject.NULL .

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

Fields
public static final Object	NULL	A sentinel value used to explicitly define a name with no value.

Public Constructors
	JSONObject () Creates a `JSONObject` with no name/value mappings.
	JSONObject ( Map copyFrom) Creates a new `JSONObject` by copying all name/value mappings from the given map.
	JSONObject ( JSONTokener readFrom) Creates a new `JSONObject` with name/value mappings from the next object in the tokener.
	JSONObject ( String json) Creates a new `JSONObject` with name/value mappings from the JSON string.
	JSONObject ( JSONObject copyFrom, String[] names) Creates a new `JSONObject` by copying mappings for the listed names from the given object.

Public Methods
JSONObject	accumulate ( String name, Object value) Appends `value` to the array already mapped to `name` .
Object	get ( String name) Returns the value mapped by `name` , or throws if no such mapping exists.
boolean	getBoolean ( String name) Returns the value mapped by `name` if it exists and is a boolean or can be coerced to a boolean, or throws otherwise.
double	getDouble ( String name) Returns the value mapped by `name` if it exists and is a double or can be coerced to a double, or throws otherwise.
int	getInt ( String name) Returns the value mapped by `name` if it exists and is an int or can be coerced to an int, or throws otherwise.
JSONArray	getJSONArray ( String name) Returns the value mapped by `name` if it exists and is a `JSONArray` , or throws otherwise.
JSONObject	getJSONObject ( String name) Returns the value mapped by `name` if it exists and is a `JSONObject` , or throws otherwise.
long	getLong ( String name) Returns the value mapped by `name` if it exists and is a long or can be coerced to a long, or throws otherwise.
String	getString ( String name) Returns the value mapped by `name` if it exists, coercing it if necessary, or throws if no such mapping exists.
boolean	has ( String name) Returns true if this object has a mapping for `name` .
boolean	isNull ( String name) Returns true if this object has no mapping for `name` or if it has a mapping whose value is `NULL` .
Iterator < String >	keys () Returns an iterator of the `String` names in this object.
int	length () Returns the number of name/value mappings in this object.
JSONArray	names () Returns an array containing the string names in this object.
static String	numberToString ( Number number) Encodes the number as a JSON string.
Object	opt ( String name) Returns the value mapped by `name` , or null if no such mapping exists.
boolean	optBoolean ( String name) Returns the value mapped by `name` if it exists and is a boolean or can be coerced to a boolean, or false otherwise.
boolean	optBoolean ( String name, boolean fallback) Returns the value mapped by `name` if it exists and is a boolean or can be coerced to a boolean, or `fallback` otherwise.
double	optDouble ( String name, double fallback) Returns the value mapped by `name` if it exists and is a double or can be coerced to a double, or `fallback` otherwise.
double	optDouble ( String name) Returns the value mapped by `name` if it exists and is a double or can be coerced to a double, or `NaN` otherwise.
int	optInt ( String name, int fallback) Returns the value mapped by `name` if it exists and is an int or can be coerced to an int, or `fallback` otherwise.
int	optInt ( String name) Returns the value mapped by `name` if it exists and is an int or can be coerced to an int, or 0 otherwise.
JSONArray	optJSONArray ( String name) Returns the value mapped by `name` if it exists and is a `JSONArray` , or null otherwise.
JSONObject	optJSONObject ( String name) Returns the value mapped by `name` if it exists and is a `JSONObject` , or null otherwise.
long	optLong ( String name) Returns the value mapped by `name` if it exists and is a long or can be coerced to a long, or 0 otherwise.
long	optLong ( String name, long fallback) Returns the value mapped by `name` if it exists and is a long or can be coerced to a long, or `fallback` otherwise.
String	optString ( String name) Returns the value mapped by `name` if it exists, coercing it if necessary, or the empty string if no such mapping exists.
String	optString ( String name, String fallback) Returns the value mapped by `name` if it exists, coercing it if necessary, or `fallback` if no such mapping exists.
JSONObject	put ( String name, int value) Maps `name` to `value` , clobbering any existing name/value mapping with the same name.
JSONObject	put ( String name, long value) Maps `name` to `value` , clobbering any existing name/value mapping with the same name.
JSONObject	put ( String name, Object value) Maps `name` to `value` , clobbering any existing name/value mapping with the same name.
JSONObject	put ( String name, boolean value) Maps `name` to `value` , clobbering any existing name/value mapping with the same name.
JSONObject	put ( String name, double value) Maps `name` to `value` , clobbering any existing name/value mapping with the same name.
JSONObject	putOpt ( String name, Object value) Equivalent to `put(name, value)` when both parameters are non-null; does nothing otherwise.
static String	quote ( String data) Encodes `data` as a JSON string.
Object	remove ( String name) Removes the named mapping if it exists; does nothing otherwise.
JSONArray	toJSONArray ( JSONArray names) Returns an array with the values corresponding to `names` .
String	toString () Encodes this object as a compact JSON string, such as: {"query":"Pizza","locations":[94043,90210]}
String	toString (int indentSpaces) Encodes this object as a human readable JSON string for debugging, such as: { "query": "Pizza", "locations": [ 94043, 90210 ] }
static Object	wrap ( Object o) Wraps the given object if necessary.

[Expand]

Inherited Methods

From class java.lang.Object

Object	clone () Creates and returns a copy of this `Object` .
boolean	equals ( Object o) Compares this instance with the specified object and indicates if they are equal.
void	finalize () Invoked when the garbage collector has detected that this instance is no longer reachable.
final Class <?>	getClass () Returns the unique instance of `Class` that represents this object's class.
int	hashCode () Returns an integer hash code for this object.
final void	notify () Causes a thread which is waiting on this object's monitor (by means of calling one of the `wait()` methods) to be woken up.
final void	notifyAll () Causes all threads which are waiting on this object's monitor (by means of calling one of the `wait()` methods) to be woken up.
String	toString () Returns a string containing a concise, human-readable description of this object.
final void	wait () Causes the calling thread to wait until another thread calls the `notify()` or `notifyAll()` method of this object.
final void	wait (long millis, int nanos) Causes the calling thread to wait until another thread calls the `notify()` or `notifyAll()` method of this object or until the specified timeout expires.
final void	wait (long millis) Causes the calling thread to wait until another thread calls the `notify()` or `notifyAll()` method of this object or until the specified timeout expires.

Fields

public static final Object NULL

Added in API level 1

A sentinel value used to explicitly define a name with no value. Unlike null , names with this value:

show up in the names() array
show up in the keys() iterator
return true for has(String)
do not throw on get(String)
are included in the encoded JSON string.

This value violates the general contract of equals(Object) by returning true when compared to null . Its toString() method returns "null".

Public Constructors

public JSONObject ()

Added in API level 1

Creates a JSONObject with no name/value mappings.

public JSONObject ( Map copyFrom)

Added in API level 1

Creates a new JSONObject by copying all name/value mappings from the given map.

Parameters

copyFrom	a map whose keys are of type `String` and whose values are of supported types.

Throws

NullPointerException	if any of the map's keys are null.

public JSONObject ( JSONTokener readFrom)

Added in API level 1

Creates a new JSONObject with name/value mappings from the next object in the tokener.

Parameters

readFrom	a tokener whose nextValue() method will yield a `JSONObject` .

Throws

JSONException	if the parse fails or doesn't yield a `JSONObject` .

public JSONObject ( String json)

Added in API level 1

Creates a new JSONObject with name/value mappings from the JSON string.

Parameters

json	a JSON-encoded string containing an object.

Throws

JSONException	if the parse fails or doesn't yield a `JSONObject` .

public JSONObject ( JSONObject copyFrom, String[] names)

Added in API level 1

Creates a new JSONObject by copying mappings for the listed names from the given object. Names that aren't present in copyFrom will be skipped.

Throws

JSONException

Public Methods

public JSONObject accumulate ( String name, Object value)

Added in API level 1

Appends value to the array already mapped to name . If this object has no mapping for name , this inserts a new mapping. If the mapping exists but its value is not an array, the existing and new values are inserted in order into a new array which is itself mapped to name . In aggregate, this allows values to be added to a mapping one at a time.

Note that append(String, Object) provides better semantics. In particular, the mapping for name will always be a JSONArray . Using accumulate will result in either a JSONArray or a mapping whose type is the type of value depending on the number of calls to it.

Parameters

value	a `JSONObject` , `JSONArray` , String, Boolean, Integer, Long, Double, `NULL` or null. May not be `NaNs` or `infinities` .

Throws

JSONException

public Object get ( String name)

Added in API level 1

Returns the value mapped by name , or throws if no such mapping exists.

Throws

JSONException	if no such mapping exists.

public boolean getBoolean ( String name)

Added in API level 1

Returns the value mapped by name if it exists and is a boolean or can be coerced to a boolean, or throws otherwise.

Throws

JSONException	if the mapping doesn't exist or cannot be coerced to a boolean.

public double getDouble ( String name)

Added in API level 1

Returns the value mapped by name if it exists and is a double or can be coerced to a double, or throws otherwise.

Throws

JSONException	if the mapping doesn't exist or cannot be coerced to a double.

public int getInt ( String name)

Added in API level 1

Returns the value mapped by name if it exists and is an int or can be coerced to an int, or throws otherwise.

Throws

JSONException	if the mapping doesn't exist or cannot be coerced to an int.

public JSONArray getJSONArray ( String name)

Added in API level 1

Returns the value mapped by name if it exists and is a JSONArray , or throws otherwise.

Throws

JSONException	if the mapping doesn't exist or is not a `JSONArray` .

public JSONObject getJSONObject ( String name)

Added in API level 1

Returns the value mapped by name if it exists and is a JSONObject , or throws otherwise.

Throws

JSONException	if the mapping doesn't exist or is not a `JSONObject` .

public long getLong ( String name)

Added in API level 1

Returns the value mapped by name if it exists and is a long or can be coerced to a long, or throws otherwise. Note that JSON represents numbers as doubles, so this is lossy ; use strings to transfer numbers via JSON.

Throws

JSONException	if the mapping doesn't exist or cannot be coerced to a long.

public String getString ( String name)

Added in API level 1

Returns the value mapped by name if it exists, coercing it if necessary, or throws if no such mapping exists.

Throws

JSONException	if no such mapping exists.

public boolean has ( String name)

Added in API level 1

Returns true if this object has a mapping for name . The mapping may be NULL .

public boolean isNull ( String name)

Added in API level 1

Returns true if this object has no mapping for name or if it has a mapping whose value is NULL .

public Iterator < String > keys ()

Added in API level 1

Returns an iterator of the String names in this object. The returned iterator supports remove , which will remove the corresponding mapping from this object. If this object is modified after the iterator is returned, the iterator's behavior is undefined. The order of the keys is undefined.

public int length ()

Added in API level 1

Returns the number of name/value mappings in this object.

public JSONArray names ()

Added in API level 1

Returns an array containing the string names in this object. This method returns null if this object contains no mappings.

public static String numberToString ( Number number)

Added in API level 1

Encodes the number as a JSON string.

Parameters

number	a finite value. May not be `NaNs` or `infinities` .

Throws

JSONException

public Object opt ( String name)

Added in API level 1

Returns the value mapped by name , or null if no such mapping exists.

public boolean optBoolean ( String name)

Added in API level 1

Returns the value mapped by name if it exists and is a boolean or can be coerced to a boolean, or false otherwise.

public boolean optBoolean ( String name, boolean fallback)

Added in API level 1

Returns the value mapped by name if it exists and is a boolean or can be coerced to a boolean, or fallback otherwise.

public double optDouble ( String name, double fallback)

Added in API level 1

Returns the value mapped by name if it exists and is a double or can be coerced to a double, or fallback otherwise.

public double optDouble ( String name)

Added in API level 1

Returns the value mapped by name if it exists and is a double or can be coerced to a double, or NaN otherwise.

public int optInt ( String name, int fallback)

Added in API level 1

Returns the value mapped by name if it exists and is an int or can be coerced to an int, or fallback otherwise.

public int optInt ( String name)

Added in API level 1

Returns the value mapped by name if it exists and is an int or can be coerced to an int, or 0 otherwise.

public JSONArray optJSONArray ( String name)

Added in API level 1

Returns the value mapped by name if it exists and is a JSONArray , or null otherwise.

public JSONObject optJSONObject ( String name)

Added in API level 1

Returns the value mapped by name if it exists and is a JSONObject , or null otherwise.

public long optLong ( String name)

Added in API level 1

Returns the value mapped by name if it exists and is a long or can be coerced to a long, or 0 otherwise. Note that JSON represents numbers as doubles, so this is lossy ; use strings to transfer numbers via JSON.

public long optLong ( String name, long fallback)

Added in API level 1

Returns the value mapped by name if it exists and is a long or can be coerced to a long, or fallback otherwise. Note that JSON represents numbers as doubles, so this is lossy ; use strings to transfer numbers via JSON.

public String optString ( String name)

Added in API level 1

Returns the value mapped by name if it exists, coercing it if necessary, or the empty string if no such mapping exists.

public String optString ( String name, String fallback)

Added in API level 1

Returns the value mapped by name if it exists, coercing it if necessary, or fallback if no such mapping exists.

public JSONObject put ( String name, int value)

Added in API level 1

Maps name to value , clobbering any existing name/value mapping with the same name.

Returns

this object.

Throws

JSONException

public JSONObject put ( String name, long value)

Added in API level 1

Maps name to value , clobbering any existing name/value mapping with the same name.

Returns

this object.

Throws

JSONException

public JSONObject put ( String name, Object value)

Added in API level 1

Maps name to value , clobbering any existing name/value mapping with the same name. If the value is null , any existing mapping for name is removed.

Parameters

value	a `JSONObject` , `JSONArray` , String, Boolean, Integer, Long, Double, `NULL` , or `null` . May not be `NaNs` or `infinities` .

Returns

this object.

Throws

JSONException

public JSONObject put ( String name, boolean value)

Added in API level 1

Maps name to value , clobbering any existing name/value mapping with the same name.

Returns

this object.

Throws

JSONException

public JSONObject put ( String name, double value)

Added in API level 1

Maps name to value , clobbering any existing name/value mapping with the same name.

Parameters

value	a finite value. May not be `NaNs` or `infinities` .

Returns

this object.

Throws

JSONException

public JSONObject putOpt ( String name, Object value)

Added in API level 1

Equivalent to put(name, value) when both parameters are non-null; does nothing otherwise.

Throws

JSONException

public static String quote ( String data)

Added in API level 1

Encodes data as a JSON string. This applies quotes and any necessary character escaping.

Parameters

data	the string to encode. Null will be interpreted as an empty string.

public Object remove ( String name)

Added in API level 1

Removes the named mapping if it exists; does nothing otherwise.

Returns

the value previously mapped by name , or null if there was no such mapping.

public JSONArray toJSONArray ( JSONArray names)

Added in API level 1

Returns an array with the values corresponding to names . The array contains null for names that aren't mapped. This method returns null if names is either null or empty.

Throws

JSONException

public String toString ()

Added in API level 1

Encodes this object as a compact JSON string, such as:

          {"query":"Pizza","locations":[94043,90210]}

Returns

a printable representation of this object.

public String toString (int indentSpaces)

Added in API level 1

Encodes this object as a human readable JSON string for debugging, such as:

          {
     "query": "Pizza",
     "locations": [
         94043,
         90210
     ]
 }

Parameters

indentSpaces	the number of spaces to indent for each level of nesting.

Throws

JSONException

public static Object wrap ( Object o)

Added in API level 19

Wraps the given object if necessary.

If the object is null or , returns NULL . If the object is a JSONArray or JSONObject , no wrapping is necessary. If the object is NULL , no wrapping is necessary. If the object is an array or Collection , returns an equivalent JSONArray . If the object is a Map , returns an equivalent JSONObject . If the object is a primitive wrapper type or String , returns the object. Otherwise if the object is from a java package, returns the result of toString . If wrapping fails, returns null.

Results

Classes

Exceptions

JSONObject

Class Overview

Summary

Fields

public static final Object NULL

Public Constructors

public JSONObject ()

public JSONObject ( Map copyFrom)

Parameters

Throws

public JSONObject ( JSONTokener readFrom)

Parameters

Throws

public JSONObject ( String json)

Parameters

Throws

public JSONObject ( JSONObject copyFrom, String[] names)

Throws

Public Methods

public JSONObject accumulate ( String name, Object value)

Parameters

Throws

public Object get ( String name)

Throws

public boolean getBoolean ( String name)

Throws

public double getDouble ( String name)

Throws

public int getInt ( String name)

Throws

public JSONArray getJSONArray ( String name)

Throws

public JSONObject getJSONObject ( String name)

Throws

public long getLong ( String name)

Throws

public String getString ( String name)

Throws

public boolean has ( String name)

public boolean isNull ( String name)

public Iterator < String > keys ()

public int length ()

public JSONArray names ()

public static String numberToString ( Number number)

Parameters

Throws

public Object opt ( String name)

public boolean optBoolean ( String name)

public boolean optBoolean ( String name, boolean fallback)

public double optDouble ( String name, double fallback)

public double optDouble ( String name)

public int optInt ( String name, int fallback)

public int optInt ( String name)

public JSONArray optJSONArray ( String name)

public JSONObject optJSONObject ( String name)

public long optLong ( String name)

public long optLong ( String name, long fallback)

public String optString ( String name)

public String optString ( String name, String fallback)

public JSONObject put ( String name, int value)

Returns

Throws

public JSONObject put ( String name, long value)

Returns

Throws

public JSONObject put ( String name, Object value)

Parameters

Returns

Throws

public JSONObject put ( String name, boolean value)

Returns

Throws

public JSONObject put ( String name, double value)

Parameters

Returns

Throws

public JSONObject putOpt ( String name, Object value)