java.lang.Object
- org.json.JSONObject

```
public class JSONObject
extends java.lang.Object
```
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 Double.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 Double.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 Double.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 value 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 a JSONException 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 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.

Field Summary

Fields
Modifier and Type Field Description

static java.lang.Object NULL
A sentinel value used to explicitly define a name with no value.

Constructor Summary

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

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`JSONObject`	`accumulate(java.lang.String name, java.lang.Object value)`	Appends `value` to the array already mapped to `name`.
`JSONObject`	`append(java.lang.String name, java.lang.Object value)`	Appends values to the array mapped to `name`.
`java.lang.Object`	`get(java.lang.String name)`	Returns the value mapped by `name`, or throws if no such mapping exists.
`boolean`	`getBoolean(java.lang.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(java.lang.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(java.lang.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(java.lang.String name)`	Returns the value mapped by `name` if it exists and is a `JSONArray`, or throws otherwise.
`JSONObject`	`getJSONObject(java.lang.String name)`	Returns the value mapped by `name` if it exists and is a `JSONObject`, or throws otherwise.
`long`	`getLong(java.lang.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.
`java.lang.String`	`getString(java.lang.String name)`	Returns the value mapped by `name` if it exists, coercing it if necessary, or throws if no such mapping exists.
`boolean`	`has(java.lang.String name)`	Returns true if this object has a mapping for `name`.
`boolean`	`isNull(java.lang.String name)`	Returns true if this object has no mapping for `name` or if it has a mapping whose value is `NULL`.
`java.util.Iterator<java.lang.String>`	`keys()`	Returns an iterator of the `String` names in this object.
`java.util.Set<java.lang.String>`	`keySet()`	Returns the set of `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 java.lang.String`	`numberToString(java.lang.Number number)`	Encodes the number as a JSON string.
`java.lang.Object`	`opt(java.lang.String name)`	Returns the value mapped by `name`, or null if no such mapping exists.
`boolean`	`optBoolean(java.lang.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(java.lang.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(java.lang.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.
`double`	`optDouble(java.lang.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.
`int`	`optInt(java.lang.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.
`int`	`optInt(java.lang.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.
`JSONArray`	`optJSONArray(java.lang.String name)`	Returns the value mapped by `name` if it exists and is a `JSONArray`, or null otherwise.
`JSONObject`	`optJSONObject(java.lang.String name)`	Returns the value mapped by `name` if it exists and is a `JSONObject`, or null otherwise.
`long`	`optLong(java.lang.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(java.lang.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.
`java.lang.String`	`optString(java.lang.String name)`	Returns the value mapped by `name` if it exists, coercing it if necessary, or the empty string if no such mapping exists.
`java.lang.String`	`optString(java.lang.String name, java.lang.String fallback)`	Returns the value mapped by `name` if it exists, coercing it if necessary, or `fallback` if no such mapping exists.
`JSONObject`	`put(java.lang.String name, boolean value)`	Maps `name` to `value`, clobbering any existing name/value mapping with the same name.
`JSONObject`	`put(java.lang.String name, double value)`	Maps `name` to `value`, clobbering any existing name/value mapping with the same name.
`JSONObject`	`put(java.lang.String name, int value)`	Maps `name` to `value`, clobbering any existing name/value mapping with the same name.
`JSONObject`	`put(java.lang.String name, long value)`	Maps `name` to `value`, clobbering any existing name/value mapping with the same name.
`JSONObject`	`put(java.lang.String name, java.lang.Object value)`	Maps `name` to `value`, clobbering any existing name/value mapping with the same name.
`JSONObject`	`putOpt(java.lang.String name, java.lang.Object value)`	Equivalent to `put(name, value)` when both parameters are non-null; does nothing otherwise.
`static java.lang.String`	`quote(java.lang.String data)`	Encodes `data` as a JSON string.
`java.lang.Object`	`remove(java.lang.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`.
`java.lang.String`	`toString()`	Encodes this object as a compact JSON string, such as:
`java.lang.String`	`toString(int indentSpaces)`	Encodes this object as a human readable JSON string for debugging, such as:
`static java.lang.Object`	`wrap(java.lang.Object o)`	Wraps the given object if necessary.

Methods inherited from class java.lang.Object
equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

- Field Detail
  - NULL
```
@NonNull
public static final java.lang.Object NULL
```
    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 Object.equals(java.lang.Object) by returning true when compared to null. Its toString() method returns "null".
- Constructor Detail
  - JSONObject
```
public JSONObject()
```
    Creates a JSONObject with no name/value mappings.
  - JSONObject
```
public JSONObject(@NonNull
                  java.util.Map copyFrom)
```
    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:
    
    java.lang.NullPointerException - if any of the map's keys are null.
  - JSONObject
```
public JSONObject(@NonNull
                  JSONTokener readFrom)
           throws JSONException
```
    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.
  - JSONObject
```
public JSONObject(@NonNull
                  java.lang.String json)
           throws JSONException
```
    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.
  - JSONObject
```
public JSONObject(@NonNull
                  JSONObject copyFrom,
                  @NonNull
                  java.lang.String[] names)
           throws JSONException
```
    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
- Method Detail
  - length
```
public int length()
```
    Returns the number of name/value mappings in this object.
  - put
```
@NonNull
public JSONObject put(@NonNull
                      java.lang.String name,
                      boolean value)
               throws JSONException
```
    Maps name to value, clobbering any existing name/value mapping with the same name.
    
    Returns:
    
    this object.
    
    Throws:
    
    JSONException
  - put
```
@NonNull
public JSONObject put(@NonNull
                      java.lang.String name,
                      double value)
               throws JSONException
```
    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
  - put
```
@NonNull
public JSONObject put(@NonNull
                      java.lang.String name,
                      int value)
               throws JSONException
```
    Maps name to value, clobbering any existing name/value mapping with the same name.
    
    Returns:
    
    this object.
    
    Throws:
    
    JSONException
  - put
```
@NonNull
public JSONObject put(@NonNull
                      java.lang.String name,
                      long value)
               throws JSONException
```
    Maps name to value, clobbering any existing name/value mapping with the same name.
    
    Returns:
    
    this object.
    
    Throws:
    
    JSONException
  - put
```
@NonNull
public JSONObject put(@NonNull
                      java.lang.String name,
                      @Nullable
                      java.lang.Object value)
               throws JSONException
```
    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
  - putOpt
```
@NonNull
public JSONObject putOpt(@Nullable
                         java.lang.String name,
                         @Nullable
                         java.lang.Object value)
                  throws JSONException
```
    Equivalent to put(name, value) when both parameters are non-null; does nothing otherwise.
    
    Throws:
    
    JSONException
  - accumulate
```
@NonNull
public JSONObject accumulate(@NonNull
                             java.lang.String name,
                             @Nullable
                             java.lang.Object value)
                      throws JSONException
```
    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
  - append
```
public JSONObject append(java.lang.String name,
                         java.lang.Object value)
                  throws JSONException
```
    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.
    
    Throws:
    
    JSONException - if name is null or if the mapping for name is non-null and is not a JSONArray.
  - remove
```
@Nullable
public java.lang.Object remove(@Nullable
                               java.lang.String name)
```
    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.
  - isNull
```
public boolean isNull(@Nullable
                      java.lang.String name)
```
    Returns true if this object has no mapping for name or if it has a mapping whose value is NULL.
  - has
```
public boolean has(@Nullable
                   java.lang.String name)
```
    Returns true if this object has a mapping for name. The mapping may be NULL.
  - get
```
@NonNull
public java.lang.Object get(@NonNull
                            java.lang.String name)
                     throws JSONException
```
    Returns the value mapped by name, or throws if no such mapping exists.
    
    Throws:
    
    JSONException - if no such mapping exists.
  - opt
```
@Nullable
public java.lang.Object opt(@Nullable
                            java.lang.String name)
```
    Returns the value mapped by name, or null if no such mapping exists.
  - getBoolean
```
public boolean getBoolean(@NonNull
                          java.lang.String name)
                   throws JSONException
```
    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.
  - optBoolean
```
public boolean optBoolean(@Nullable
                          java.lang.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.
  - optBoolean
```
public boolean optBoolean(@Nullable
                          java.lang.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.
  - getDouble
```
public double getDouble(@NonNull
                        java.lang.String name)
                 throws JSONException
```
    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.
  - optDouble
```
public double optDouble(@Nullable
                        java.lang.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.
  - optDouble
```
public double optDouble(@Nullable
                        java.lang.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.
  - getInt
```
public int getInt(@NonNull
                  java.lang.String name)
           throws JSONException
```
    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.
  - optInt
```
public int optInt(@Nullable
                  java.lang.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.
  - optInt
```
public int optInt(@Nullable
                  java.lang.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.
  - getLong
```
public long getLong(@NonNull
                    java.lang.String name)
             throws JSONException
```
    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.
  - optLong
```
public long optLong(@Nullable
                    java.lang.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. Note that JSON represents numbers as doubles, so this is lossy; use strings to transfer numbers via JSON.
  - optLong
```
public long optLong(@Nullable
                    java.lang.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. Note that JSON represents numbers as doubles, so this is lossy; use strings to transfer numbers via JSON.
  - getString
```
@NonNull
public java.lang.String getString(@NonNull
                                  java.lang.String name)
                           throws JSONException
```
    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.
  - optString
```
@NonNull
public java.lang.String optString(@Nullable
                                  java.lang.String name)
```
    Returns the value mapped by name if it exists, coercing it if necessary, or the empty string if no such mapping exists.
  - optString
```
@NonNull
public java.lang.String optString(@Nullable
                                  java.lang.String name,
                                  @NonNull
                                  java.lang.String fallback)
```
    Returns the value mapped by name if it exists, coercing it if necessary, or fallback if no such mapping exists.
  - getJSONArray
```
@NonNull
public JSONArray getJSONArray(@NonNull
                              java.lang.String name)
                       throws JSONException
```
    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.
  - optJSONArray
```
@Nullable
public JSONArray optJSONArray(@Nullable
                              java.lang.String name)
```
    Returns the value mapped by name if it exists and is a JSONArray, or null otherwise.
  - getJSONObject
```
@NonNull
public JSONObject getJSONObject(@NonNull
                                java.lang.String name)
                         throws JSONException
```
    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.
  - optJSONObject
```
@Nullable
public JSONObject optJSONObject(@Nullable
                                java.lang.String name)
```
    Returns the value mapped by name if it exists and is a JSONObject, or null otherwise.
  - toJSONArray
```
@Nullable
public JSONArray toJSONArray(@Nullable
                             JSONArray names)
                      throws JSONException
```
    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
  - keys
```
@NonNull
public java.util.Iterator<java.lang.String> keys()
```
    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.
  - keySet
```
public java.util.Set<java.lang.String> keySet()
```
    Returns the set of String names in this object. The returned set is a view of the keys in this object. Set.remove(Object) will remove the corresponding mapping from this object and set iterator behaviour is undefined if this object is modified after it is returned.
    See keys().
  - names
```
@Nullable
public JSONArray names()
```
    Returns an array containing the string names in this object. This method returns null if this object contains no mappings.
  - toString
```
@NonNull
public java.lang.String toString()
```
    Encodes this object as a compact JSON string, such as:
    {"query":"Pizza","locations":[94043,90210]}
    Overrides:
    
    toString in class java.lang.Object
  - toString
```
@NonNull
public java.lang.String toString(int indentSpaces)
                          throws JSONException
```
    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
  - numberToString
```
@NonNull
public static java.lang.String numberToString(@NonNull
                                              java.lang.Number number)
                                       throws JSONException
```
    Encodes the number as a JSON string.
    
    Parameters:
    
    number - a finite value. May not be NaNs or infinities.
    
    Throws:
    
    JSONException
  - quote
```
@NonNull
public static java.lang.String quote(@Nullable
                                     java.lang.String data)
```
    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.
  - wrap
```
@Nullable
public static java.lang.Object wrap(@Nullable
                                    java.lang.Object o)
```
    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.

Class JSONObject

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

NULL

Constructor Detail

JSONObject

JSONObject

JSONObject

JSONObject

JSONObject

Method Detail

length

put

put

put

put

put

putOpt

accumulate

append

remove

isNull

has

get

opt

getBoolean

optBoolean

optBoolean

getDouble

optDouble

optDouble

getInt

optInt

optInt

getLong

optLong

optLong

getString

optString

optString

getJSONArray

optJSONArray

getJSONObject

optJSONObject

toJSONArray

keys

keySet

names

toString

toString

numberToString

quote

wrap