@java.lang.SuppressWarnings({ "unchecked", "rawtypes" }) public class JSONObject extends java.lang.Object
A JSONObject is an unordered collection of name/value pairs. Its
external form is a string wrapped in curly braces with colons between the
names and values, and commas between the values and names. The internal form
is an object having 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
, or String
. 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.
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.Modifiers | Name | Description |
---|---|---|
static class |
JSONObject.Null |
This class has been deprecated, should no longer be referenced and has been removed from Grails 3.1. |
Modifiers | Name | Description |
---|---|---|
static java.lang.Object |
NULL |
It is sometimes more convenient and less ambiguous to have a
NULL object than to use Java's null value.
|
Type Params | Return Type | Name and description |
---|---|---|
|
java.lang.Object |
JSONObject() Construct an empty JSONObject. |
|
java.lang.Object |
JSONObject(JSONObject jo, java.lang.String[] sa) Construct a JSONObject from a subset of another JSONObject. |
|
java.lang.Object |
JSONObject(JSONTokener x) Construct a JSONObject from a JSONTokener. |
|
java.lang.Object |
JSONObject(java.util.Map map) Construct a JSONObject from a Map. |
|
java.lang.Object |
JSONObject(java.lang.String string) Construct a JSONObject from a string. |
|
JSONObject |
accumulate(java.lang.String key, java.lang.Object value) Accumulate values under a key. |
|
void |
clear() |
|
boolean |
containsKey(java.lang.Object o) |
|
boolean |
containsValue(java.lang.Object o) |
|
static java.lang.String |
dateToString(java.util.Date d) |
|
protected static void |
encodeToWriter(java.lang.CharSequence str, java.io.Writer writer) |
|
java.util.Set |
entrySet() |
|
boolean |
equals(java.lang.Object o) |
|
java.lang.Object |
get(java.lang.String key) Get the value object associated with a key. |
|
java.lang.Object |
get(java.lang.Object o) |
|
boolean |
getBoolean(java.lang.String key) Get the boolean value associated with a key. |
|
double |
getDouble(java.lang.String key) Get the double value associated with a key. |
|
int |
getInt(java.lang.String key) Get the int value associated with a key. |
|
JSONArray |
getJSONArray(java.lang.String key) Get the JSONArray value associated with a key. |
|
JSONObject |
getJSONObject(java.lang.String key) Get the JSONObject value associated with a key. |
|
long |
getLong(java.lang.String key) Get the long value associated with a key. |
|
java.lang.String |
getString(java.lang.String key) Get the string associated with a key. |
|
boolean |
has(java.lang.String key) Determine if the JSONObject contains a specific key. |
|
int |
hashCode() |
|
boolean |
isEmpty() |
|
boolean |
isNull(java.lang.String key) Determine if the value associated with the key is null or if there is no value. |
|
java.util.Set |
keySet() |
|
java.util.Iterator |
keys() Get an enumeration of the keys of the JSONObject. |
|
int |
length() Get the number of keys stored in the JSONObject. |
|
JSONArray |
names() Produce a JSONArray containing the names of the elements of this JSONObject. |
|
static java.lang.String |
numberToString(java.lang.Number n) Produce a string from a number. |
|
java.lang.Object |
opt(java.lang.String key) Get an optional value associated with a key. |
|
boolean |
optBoolean(java.lang.String key) Get an optional boolean associated with a key. |
|
boolean |
optBoolean(java.lang.String key, boolean defaultValue) Get an optional boolean associated with a key. |
|
double |
optDouble(java.lang.String key) Get an optional double associated with a key, or NaN if there is no such key or if its value is not a number. |
|
double |
optDouble(java.lang.String key, double defaultValue) Get an optional double associated with a key, or the defaultValue if there is no such key or if its value is not a number. |
|
int |
optInt(java.lang.String key) Get an optional int value associated with a key, or zero if there is no such key or if the value is not a number. |
|
int |
optInt(java.lang.String key, int defaultValue) Get an optional int value associated with a key, or the default if there is no such key or if the value is not a number. |
|
JSONArray |
optJSONArray(java.lang.String key) Get an optional JSONArray associated with a key. |
|
JSONObject |
optJSONObject(java.lang.String key) Get an optional JSONObject associated with a key. |
|
long |
optLong(java.lang.String key) Get an optional long value associated with a key, or zero if there is no such key or if the value is not a number. |
|
long |
optLong(java.lang.String key, long defaultValue) Get an optional long value associated with a key, or the default if there is no such key or if the value is not a number. |
|
java.lang.String |
optString(java.lang.String key) Get an optional string associated with a key. |
|
java.lang.String |
optString(java.lang.String key, java.lang.String defaultValue) Get an optional string associated with a key. |
|
JSONObject |
put(java.lang.String key, boolean value) Put a key/boolean pair in the JSONObject. |
|
JSONObject |
put(java.lang.String key, double value) Put a key/double pair in the JSONObject. |
|
JSONObject |
put(java.lang.String key, int value) Put a key/int pair in the JSONObject. |
|
JSONObject |
put(java.lang.String key, long value) Put a key/long pair in the JSONObject. |
|
JSONObject |
put(java.lang.String key, java.lang.Object value) Put a key/value pair in the JSONObject. |
|
java.lang.Object |
put(java.lang.Object o, java.lang.Object o1) |
|
void |
putAll(java.util.Map map) |
|
JSONObject |
putOpt(java.lang.String key, java.lang.Object value) Put a key/value pair in the JSONObject, but only if the key and the value are both non-null. |
|
static java.lang.String |
quote(java.lang.String string) Produce a string in double quotes with backslash sequences in all the right places. |
|
java.lang.Object |
remove(java.lang.String key) Remove a name and its value, if present. |
|
java.lang.Object |
remove(java.lang.Object o) |
|
int |
size() |
|
JSONArray |
toJSONArray(JSONArray names) Produce a JSONArray containing the values of the members of this JSONObject. |
|
java.lang.String |
toString() Make an JSON text of this JSONObject. |
|
java.lang.String |
toString(int indentFactor) Make a prettyprinted JSON text of this JSONObject. |
|
java.util.Collection |
values() |
|
java.io.Writer |
write(java.io.Writer writer) Write the contents of the JSONObject as JSON text to a writer. |
|
java.io.Writer |
writeTo(java.io.Writer out) |
Methods inherited from class | Name |
---|---|
class java.lang.Object |
java.lang.Object#wait(long, int), java.lang.Object#wait(long), java.lang.Object#wait(), java.lang.Object#equals(java.lang.Object), java.lang.Object#toString(), java.lang.Object#hashCode(), java.lang.Object#getClass(), java.lang.Object#notify(), java.lang.Object#notifyAll() |
It is sometimes more convenient and less ambiguous to have a
NULL
object than to use Java's null
value.
JSONObject.NULL.equals(null)
returns true
.
JSONObject.NULL.toString()
returns "null"
.
Construct an empty JSONObject.
Construct a JSONObject from a subset of another JSONObject. An array of strings is used to identify the keys that should be copied. Missing keys are ignored.
jo
- A JSONObject.sa
- An array of strings.Construct a JSONObject from a JSONTokener.
x
- A JSONTokener object containing the source string.Construct a JSONObject from a Map.
map
- A map object that can be used to initialize the contents of
the JSONObject.Construct a JSONObject from a string. This is the most commonly used JSONObject constructor.
string
- A string beginning
with {
(left brace) and ending
with }
(right brace).Accumulate values under a key. It is similar to the put method except that if there is already an object stored under the key then a JSONArray is stored under the key to hold all of the accumulated values. If there is already a JSONArray, then the new value is appended to it. In contrast, the put method replaces the previous value.
key
- A key string.value
- An object to be accumulated under the key.Get the value object associated with a key.
key
- A key string.Get the boolean value associated with a key.
key
- A key string.Get the double value associated with a key.
key
- A key string.Get the int value associated with a key. If the number value is too large for an int, it will be clipped.
key
- A key string.Get the JSONArray value associated with a key.
key
- A key string.Get the JSONObject value associated with a key.
key
- A key string.Get the long value associated with a key. If the number value is too long for a long, it will be clipped.
key
- A key string.Get the string associated with a key.
key
- A key string.Determine if the JSONObject contains a specific key.
key
- A key string.Determine if the value associated with the key is null or if there is no value.
key
- A key string.Get an enumeration of the keys of the JSONObject.
Get the number of keys stored in the JSONObject.
Produce a JSONArray containing the names of the elements of this JSONObject.
Produce a string from a number.
n
- A NumberGet an optional value associated with a key.
key
- A key string.Get an optional boolean associated with a key. It returns false if there is no such key, or if the value is not Boolean.TRUE or the String "true".
key
- A key string.Get an optional boolean associated with a key. It returns the defaultValue if there is no such key, or if it is not a Boolean or the String "true" or "false" (case insensitive).
key
- A key string.defaultValue
- The default.Get an optional double associated with a key, or NaN if there is no such key or if its value is not a number. If the value is a string, an attempt will be made to evaluate it as a number.
key
- A string which is the key.Get an optional double associated with a key, or the defaultValue if there is no such key or if its value is not a number. If the value is a string, an attempt will be made to evaluate it as a number.
key
- A key string.defaultValue
- The default.Get an optional int value associated with a key, or zero if there is no such key or if the value is not a number. If the value is a string, an attempt will be made to evaluate it as a number.
key
- A key string.Get an optional int value associated with a key, or the default if there is no such key or if the value is not a number. If the value is a string, an attempt will be made to evaluate it as a number.
key
- A key string.defaultValue
- The default.Get an optional JSONArray associated with a key. It returns null if there is no such key, or if its value is not a JSONArray.
key
- A key string.Get an optional JSONObject associated with a key. It returns null if there is no such key, or if its value is not a JSONObject.
key
- A key string.Get an optional long value associated with a key, or zero if there is no such key or if the value is not a number. If the value is a string, an attempt will be made to evaluate it as a number.
key
- A key string.Get an optional long value associated with a key, or the default if there is no such key or if the value is not a number. If the value is a string, an attempt will be made to evaluate it as a number.
key
- A key string.defaultValue
- The default.Get an optional string associated with a key. It returns an empty string if there is no such key. If the value is not a string and is not null, then it is coverted to a string.
key
- A key string.Get an optional string associated with a key. It returns the defaultValue if there is no such key.
key
- A key string.defaultValue
- The default.Put a key/boolean pair in the JSONObject.
key
- A key string.value
- A boolean which is the value.Put a key/double pair in the JSONObject.
key
- A key string.value
- A double which is the value.Put a key/int pair in the JSONObject.
key
- A key string.value
- An int which is the value.Put a key/long pair in the JSONObject.
key
- A key string.value
- A long which is the value.Put a key/value pair in the JSONObject. If the value is null, then the key will be removed from the JSONObject if it is present.
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.Put a key/value pair in the JSONObject, but only if the key and the value are both non-null.
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.Produce a string in double quotes with backslash sequences in all the right places. A backslash will be inserted within , allowing JSON text to be delivered in HTML. In JSON text, a string cannot contain a control character or an unescaped quote or backslash.
string
- A StringRemove a name and its value, if present.
key
- The name to be removed.Produce a JSONArray containing the values of the members of this JSONObject.
names
- A JSONArray containing a list of key strings. This
determines the sequence of the values in the result.Make an JSON text of this JSONObject. For compactness, no whitespace is added. If this would not result in a syntactically correct JSON text, then null will be returned instead.
Warning: This method assumes that the data structure is acyclical.{
(left brace) and ending
with }
(right brace).Make a prettyprinted JSON text of this JSONObject.
Warning: This method assumes that the data structure is acyclical.indentFactor
- The number of spaces to add to each level of
indentation.{
(left brace) and ending
with }
(right brace).Write the contents of the JSONObject as JSON text to a writer. For compactness, no whitespace is added.
Warning: This method assumes that the data structure is acyclical.