JSONObject
open class JSONObject
kotlin.Any | |
↳ | org.json.JSONObject |
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 usingdoubleValue
. Strings that can be coerced usingDouble#valueOf(String)
will be. - When the requested type is an int, other
Number
types will be coerced usingintValue
. Strings that can be coerced usingDouble#valueOf(String)
will be, and then cast to int. - When the requested type is a long, other
Number
types will be coerced usinglongValue
. Strings that can be coerced usingDouble#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
String#valueOf(Object)
. Although null cannot be coerced, the sentinel valueJSONObject#NULL
is coerced to the string "null".
This class can look up both mandatory and optional values:
- Use
getType()
to retrieve a mandatory value. This fails with aJSONException
if the requested name has no value or if the value cannot be coerced to the requested type. - Use
optType()
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 org.json.JSONObject#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, 3rd edition Item 19, "Design and Document for inheritance or else prohibit it" for further information.
Summary
Public constructors | |
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Creates a |
|
JSONObject(copyFrom: MutableMap<Any?, Any?>) Creates a new |
|
JSONObject(readFrom: JSONTokener) Creates a new |
|
JSONObject(json: String) Creates a new |
|
JSONObject(copyFrom: JSONObject, names: Array<String!>) Creates a new |
Public methods | |
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open JSONObject |
accumulate(name: String, value: Any?) Appends |
open JSONObject |
Appends values to the array mapped to |
open Any |
Returns the value mapped by |
open Boolean |
getBoolean(name: String) Returns the value mapped by |
open Double |
Returns the value mapped by |
open Int |
Returns the value mapped by |
open JSONArray |
getJSONArray(name: String) Returns the value mapped by |
open JSONObject |
getJSONObject(name: String) Returns the value mapped by |
open Long |
Returns the value mapped by |
open String |
Returns the value mapped by |
open Boolean |
Returns true if this object has a mapping for |
open Boolean |
Returns true if this object has no mapping for |
open MutableIterator<String!> |
keys() Returns an iterator of the |
open Int |
length() Returns the number of name/value mappings in this object. |
open JSONArray? |
names() Returns an array containing the string names in this object. |
open static String |
numberToString(number: Number) Encodes the number as a JSON string. |
open Any? |
Returns the value mapped by |
open Boolean |
optBoolean(name: String?) Returns the value mapped by |
open Boolean |
optBoolean(name: String?, fallback: Boolean) Returns the value mapped by |
open Double |
Returns the value mapped by |
open Double |
Returns the value mapped by |
open Int |
Returns the value mapped by |
open Int |
Returns the value mapped by |
open JSONArray? |
optJSONArray(name: String?) Returns the value mapped by |
open JSONObject? |
optJSONObject(name: String?) Returns the value mapped by |
open Long |
Returns the value mapped by |
open Long |
Returns the value mapped by |
open String |
Returns the value mapped by |
open String |
Returns the value mapped by |
open JSONObject |
Maps |
open JSONObject |
Maps |
open JSONObject |
Maps |
open JSONObject |
Maps |
open JSONObject |
Maps |
open JSONObject |
Equivalent to |
open static String |
Encodes |
open Any? |
Removes the named mapping if it exists; does nothing otherwise. |
open JSONArray? |
toJSONArray(names: JSONArray?) Returns an array with the values corresponding to |
open String |
toString() Encodes this object as a compact JSON string, such as: {"query":"Pizza","locations":[94043,90210]} |
open String |
Encodes this object as a human readable JSON string for debugging, such as: { "query": "Pizza", "locations": [ 94043, 90210 ] } |
open static Any? |
Wraps the given object if necessary. |
Properties | |
---|---|
static Any |
A sentinel value used to explicitly define a name with no value. |
Public constructors
JSONObject
JSONObject(copyFrom: MutableMap<Any?, Any?>)
Creates a new JSONObject
by copying all name/value mappings from the given map.
Parameters | |
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copyFrom |
MutableMap<Any?, Any?>: a map whose keys are of type String and whose values are of supported types. |
Exceptions | |
---|---|
java.lang.NullPointerException |
if any of the map's keys are null. |
JSONObject
JSONObject(readFrom: JSONTokener)
Creates a new JSONObject
with name/value mappings from the next object in the tokener.
Parameters | |
---|---|
readFrom |
JSONTokener: a tokener whose nextValue() method will yield a JSONObject . |
Exceptions | |
---|---|
org.json.JSONException |
if the parse fails or doesn't yield a JSONObject . |
JSONObject
JSONObject(json: String)
Creates a new JSONObject
with name/value mappings from the JSON string.
Parameters | |
---|---|
json |
String: a JSON-encoded string containing an object. |
Exceptions | |
---|---|
org.json.JSONException |
if the parse fails or doesn't yield a JSONObject . |
JSONObject
JSONObject(
copyFrom: JSONObject,
names: Array<String!>)
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.
Public methods
accumulate
open fun accumulate(
name: String,
value: Any?
): JSONObject
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(java.lang.String,java.lang.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 | |
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value |
Any?: a JSONObject , JSONArray , String, Boolean, Integer, Long, Double, NULL or null. May not be NaNs or infinities . |
append
open fun append(
name: String,
value: Any?
): JSONObject
Appends values to the array mapped to name
. A new JSONArray
mapping for name
will be inserted if no mapping exists. If the existing mapping for name
is not a JSONArray
, a JSONException
will be thrown.
Exceptions | |
---|---|
org.json.JSONException |
if name is null or if the mapping for name is non-null and is not a JSONArray . |
get
open fun get(name: String): Any
Returns the value mapped by name
, or throws if no such mapping exists.
Exceptions | |
---|---|
org.json.JSONException |
if no such mapping exists. |
getBoolean
open fun getBoolean(name: String): Boolean
Returns the value mapped by name
if it exists and is a boolean or can be coerced to a boolean, or throws otherwise.
Exceptions | |
---|---|
org.json.JSONException |
if the mapping doesn't exist or cannot be coerced to a boolean. |
getDouble
open fun getDouble(name: String): Double
Returns the value mapped by name
if it exists and is a double or can be coerced to a double, or throws otherwise.
Exceptions | |
---|---|
org.json.JSONException |
if the mapping doesn't exist or cannot be coerced to a double. |
getInt
open fun getInt(name: String): Int
Returns the value mapped by name
if it exists and is an int or can be coerced to an int, or throws otherwise.
Exceptions | |
---|---|
org.json.JSONException |
if the mapping doesn't exist or cannot be coerced to an int. |
getJSONArray
open fun getJSONArray(name: String): JSONArray
Returns the value mapped by name
if it exists and is a JSONArray
, or throws otherwise.
Exceptions | |
---|---|
org.json.JSONException |
if the mapping doesn't exist or is not a JSONArray . |
getJSONObject
open fun getJSONObject(name: String): JSONObject
Returns the value mapped by name
if it exists and is a JSONObject
, or throws otherwise.
Exceptions | |
---|---|
org.json.JSONException |
if the mapping doesn't exist or is not a JSONObject . |
getLong
open fun getLong(name: String): Long
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.
Exceptions | |
---|---|
org.json.JSONException |
if the mapping doesn't exist or cannot be coerced to a long. |
getString
open fun getString(name: String): String
Returns the value mapped by name
if it exists, coercing it if necessary, or throws if no such mapping exists.
Exceptions | |
---|---|
org.json.JSONException |
if no such mapping exists. |
has
open fun has(name: String?): Boolean
Returns true if this object has a mapping for name
. The mapping may be NULL
.
isNull
open fun isNull(name: String?): Boolean
Returns true if this object has no mapping for name
or if it has a mapping whose value is NULL
.
keys
open fun keys(): MutableIterator<String!>
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.
length
open fun length(): Int
Returns the number of name/value mappings in this object.
names
open fun names(): JSONArray?
Returns an array containing the string names in this object. This method returns null if this object contains no mappings.
numberToString
open static fun numberToString(number: Number): String
Encodes the number as a JSON string.
Parameters | |
---|---|
number |
Number: a finite value. May not be NaNs or infinities . |
opt
open fun opt(name: String?): Any?
Returns the value mapped by name
, or null if no such mapping exists.
optBoolean
open fun optBoolean(name: String?): Boolean
Returns the value mapped by name
if it exists and is a boolean or can be coerced to a boolean, or false otherwise.
optBoolean
open fun optBoolean(
name: String?,
fallback: Boolean
): Boolean
Returns the value mapped by name
if it exists and is a boolean or can be coerced to a boolean, or fallback
otherwise.
optDouble
open fun optDouble(name: String?): Double
Returns the value mapped by name
if it exists and is a double or can be coerced to a double, or NaN
otherwise.
optDouble
open fun optDouble(
name: String?,
fallback: Double
): Double
Returns the value mapped by name
if it exists and is a double or can be coerced to a double, or fallback
otherwise.
optInt
open fun optInt(name: String?): Int
Returns the value mapped by name
if it exists and is an int or can be coerced to an int, or 0 otherwise.
optInt
open fun optInt(
name: String?,
fallback: Int
): Int
Returns the value mapped by name
if it exists and is an int or can be coerced to an int, or fallback
otherwise.
optJSONArray
open fun optJSONArray(name: String?): JSONArray?
Returns the value mapped by name
if it exists and is a JSONArray
, or null otherwise.
optJSONObject
open fun optJSONObject(name: String?): JSONObject?
Returns the value mapped by name
if it exists and is a JSONObject
, or null otherwise.
optLong
open fun optLong(name: String?): Long
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.
optLong
open fun optLong(
name: String?,
fallback: Long
): Long
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.
optString
open fun optString(name: String?): String
Returns the value mapped by name
if it exists, coercing it if necessary, or the empty string if no such mapping exists.
optString
open fun optString(
name: String?,
fallback: String
): String
Returns the value mapped by name
if it exists, coercing it if necessary, or fallback
if no such mapping exists.
put
open fun put(
name: String,
value: Boolean
): JSONObject
Maps name
to value
, clobbering any existing name/value mapping with the same name.
Return | |
---|---|
JSONObject |
this object. |
put
open fun put(
name: String,
value: Double
): JSONObject
Maps name
to value
, clobbering any existing name/value mapping with the same name.
Parameters | |
---|---|
value |
Double: a finite value. May not be NaNs or infinities . |
Return | |
---|---|
JSONObject |
this object. |
put
open fun put(
name: String,
value: Int
): JSONObject
Maps name
to value
, clobbering any existing name/value mapping with the same name.
Return | |
---|---|
JSONObject |
this object. |
put
open fun put(
name: String,
value: Long
): JSONObject
Maps name
to value
, clobbering any existing name/value mapping with the same name.
Return | |
---|---|
JSONObject |
this object. |
put
open fun put(
name: String,
value: Any?
): JSONObject
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 |
Any?: a JSONObject , JSONArray , String, Boolean, Integer, Long, Double, NULL , or null . May not be NaNs or infinities . |
Return | |
---|---|
JSONObject |
this object. |
putOpt
open fun putOpt(
name: String?,
value: Any?
): JSONObject
Equivalent to put(name, value)
when both parameters are non-null; does nothing otherwise.
quote
open static fun quote(data: String?): String
Encodes data
as a JSON string. This applies quotes and any necessary character escaping.
Parameters | |
---|---|
data |
String?: the string to encode. Null will be interpreted as an empty string. |
remove
open fun remove(name: String?): Any?
Removes the named mapping if it exists; does nothing otherwise.
Return | |
---|---|
Any? |
the value previously mapped by name , or null if there was no such mapping. |
toJSONArray
open fun toJSONArray(names: JSONArray?): JSONArray?
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.
toString
open fun toString(): String
Encodes this object as a compact JSON string, such as:
{"query":"Pizza","locations":[94043,90210]}
Return | |
---|---|
String |
a string representation of the object. |
toString
open fun toString(indentSpaces: Int): String
Encodes this object as a human readable JSON string for debugging, such as:
{ "query": "Pizza", "locations": [ 94043, 90210 ] }
Parameters | |
---|---|
indentSpaces |
Int: the number of spaces to indent for each level of nesting. |
wrap
open static fun wrap(o: Any?): Any?
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.
Properties
NULL
static val NULL: Any
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
forhas(java.lang.String)
- do not throw on
get(java.lang.String)
- are included in the encoded JSON string.
This value violates the general contract of Object#equals
by returning true when compared to null
. Its #toString method returns "null".