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org.json
public class: JSONObject [javadoc | source]
java.lang.Object
   org.json.JSONObject
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, 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 coercion 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 syntax rules. The constructors are more forgiving in the texts they will accept:

Field Summary
public static final  Object NULL    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"
Constructor:
 public JSONObject() 
 public JSONObject(JSONTokener x) throws JSONException 
    Construct a JSONObject from a JSONTokener.
    Parameters:
    x - A JSONTokener object containing the source string.
    Throws:
    JSONException - If there is a syntax error in the source string or a duplicated key.
 public JSONObject(Map map) 
    Construct a JSONObject from a Map.
    Parameters:
    map - A map object that can be used to initialize the contents of the JSONObject.
 public JSONObject(Object bean) 
    Construct a JSONObject from an Object using bean getters. It reflects on all of the public methods of the object. For each of the methods with no parameters and a name starting with "get" or "is" followed by an uppercase letter, the method is invoked, and a key and the value returned from the getter method are put into the new JSONObject. The key is formed by removing the "get" or "is" prefix. If the second remaining character is not upper case, then the first character is converted to lower case. For example, if an object has a method named "getName", and if the result of calling object.getName() is "Larry Fine", then the JSONObject will contain "name": "Larry Fine".
    Parameters:
    bean - An object that has getter methods that should be used to make a JSONObject.
 public JSONObject(String source) throws JSONException 
    Construct a JSONObject from a source JSON text string. This is the most commonly used JSONObject constructor.
    Parameters:
    source - A string beginning with { (left brace) and ending with } (right brace).
    Throws:
    JSONException - If there is a syntax error in the source string or a duplicated key.
    exception: JSONException - If there is a syntax error in the source string or a duplicated key.
 public JSONObject(JSONObject jo,
    String[] names) throws JSONException 
    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.
    Parameters:
    jo - A JSONObject.
    names - An array of strings.
    Throws:
    JSONException - If a value is a non-finite number or if a name is duplicated.
    exception: JSONException - If a value is a non-finite number or if a name is duplicated.
 public JSONObject(Map map,
    boolean includeSuperClass) 
    Construct a JSONObject from a Map. Note: Use this constructor when the map contains .
    Parameters:
    map - - A map with Key-Bean data.
    includeSuperClass - - Tell whether to include the super class properties.
 public JSONObject(Object bean,
    boolean includeSuperClass) 
    Construct a JSONObject from an Object using bean getters. It reflects on all of the public methods of the object. For each of the methods with no parameters and a name starting with "get" or "is" followed by an uppercase letter, the method is invoked, and a key and the value returned from the getter method are put into the new JSONObject. The key is formed by removing the "get" or "is" prefix. If the second remaining character is not upper case, then the first character is converted to lower case.
    Parameters:
    bean - An object that has getter methods that should be used to make a JSONObject.
    includeSuperClass - If true, include the super class properties.
 public JSONObject(Object object,
    String[] names) 
    Construct a JSONObject from an Object, using reflection to find the public members. The resulting JSONObject's keys will be the strings from the names array, and the values will be the field values associated with those keys in the object. If a key is not found or not visible, then it will not be copied into the new JSONObject.
    Parameters:
    object - An object that has fields that should be used to make a JSONObject.
    names - An array of strings, the names of the fields to be obtained from the object.
Method from org.json.JSONObject Summary:
accumulate,   append,   doubleToString,   get,   getBoolean,   getDouble,   getInt,   getJSONArray,   getJSONObject,   getLong,   getNames,   getNames,   getString,   has,   isNull,   isStandardProperty,   keys,   length,   names,   numberToString,   opt,   optBoolean,   optBoolean,   optDouble,   optDouble,   optInt,   optInt,   optJSONArray,   optJSONObject,   optLong,   optLong,   optString,   optString,   put,   put,   put,   put,   put,   put,   put,   putOnce,   putOpt,   quote,   remove,   sortedKeys,   stringToValue,   testValidity,   toJSONArray,   toString,   toString,   toString,   valueToString,   valueToString,   write
Methods from java.lang.Object:
clone,   equals,   finalize,   getClass,   hashCode,   notify,   notifyAll,   toString,   wait,   wait,   wait
Method from org.json.JSONObject Detail:
 public JSONObject accumulate(String key,
    Object value) throws JSONException 
    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.
 public JSONObject append(String key,
    Object value) throws JSONException 
    Append values to the array under a key. If the key does not exist in the JSONObject, then the key is put in the JSONObject with its value being a JSONArray containing the value parameter. If the key was already associated with a JSONArray, then the value parameter is appended to it.
 public static String doubleToString(double d) 
    Produce a string from a double. The string "null" will be returned if the number is not finite.
 public Object get(String key) throws JSONException 
    Get the value object associated with a key.
 public boolean getBoolean(String key) throws JSONException 
    Get the boolean value associated with a key.
 public double getDouble(String key) throws JSONException 
    Get the double value associated with a key.
 public int getInt(String key) throws JSONException 
    Get the int value associated with a key. If the number value is too large for an int, it will be clipped.
 public JSONArray getJSONArray(String key) throws JSONException 
    Get the JSONArray value associated with a key.
 public JSONObject getJSONObject(String key) throws JSONException 
    Get the JSONObject value associated with a key.
 public long getLong(String key) throws JSONException 
    Get the long value associated with a key. If the number value is too long for a long, it will be clipped.
 public static String[] getNames(JSONObject jo) 
    Get an array of field names from a JSONObject.
 public static String[] getNames(Object object) 
    Get an array of field names from an Object.
 public String getString(String key) throws JSONException 
    Get the string associated with a key.
 public boolean has(String key) 
    Determine if the JSONObject contains a specific key.
 public boolean isNull(String key) 
    Determine if the value associated with the key is null or if there is no value.
 static boolean isStandardProperty(Class clazz) 
 public Iterator keys() 
    Get an enumeration of the keys of the JSONObject.
 public int length() 
    Get the number of keys stored in the JSONObject.
 public JSONArray names() 
    Produce a JSONArray containing the names of the elements of this JSONObject.
 public static String numberToString(Number n) throws JSONException 
    Produce a string from a Number.
 public Object opt(String key) 
    Get an optional value associated with a key.
 public boolean optBoolean(String key) 
    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".
 public boolean optBoolean(String key,
    boolean defaultValue) 
    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).
 public double optDouble(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. If the value is a string, an attempt will be made to evaluate it as a number.
 public double optDouble(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. If the value is a string, an attempt will be made to evaluate it as a number.
 public int optInt(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. If the value is a string, an attempt will be made to evaluate it as a number.
 public int optInt(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. If the value is a string, an attempt will be made to evaluate it as a number.
 public JSONArray optJSONArray(String key) 
    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.
 public JSONObject optJSONObject(String key) 
    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.
 public long optLong(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. If the value is a string, an attempt will be made to evaluate it as a number.
 public long optLong(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. If the value is a string, an attempt will be made to evaluate it as a number.
 public String optString(String key) 
    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.
 public String optString(String key,
    String defaultValue) 
    Get an optional string associated with a key. It returns the defaultValue if there is no such key.
 public JSONObject put(String key,
    Collection value) throws JSONException 
    Put a key/value pair in the JSONObject, where the value will be a JSONArray which is produced from a Collection.
 public JSONObject put(String key,
    boolean value) throws JSONException 
    Put a key/boolean pair in the JSONObject.
 public JSONObject put(String key,
    double value) throws JSONException 
    Put a key/double pair in the JSONObject.
 public JSONObject put(String key,
    int value) throws JSONException 
    Put a key/int pair in the JSONObject.
 public JSONObject put(String key,
    long value) throws JSONException 
    Put a key/long pair in the JSONObject.
 public JSONObject put(String key,
    Map value) throws JSONException 
    Put a key/value pair in the JSONObject, where the value will be a JSONObject which is produced from a Map.
 public JSONObject put(String key,
    Object value) throws JSONException 
    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.
 public JSONObject putOnce(String key,
    Object value) throws JSONException 
    Put a key/value pair in the JSONObject, but only if the key and the value are both non-null, and only if there is not already a member with that name.
 public JSONObject putOpt(String key,
    Object value) throws JSONException 
    Put a key/value pair in the JSONObject, but only if the key and the value are both non-null.
 public static String quote(String string) 
    Produce a string in double quotes with backslash sequences in all the right places. A backslash will be inserted within
 public Object remove(String key) 
    Remove a name and its value, if present.
 public Iterator sortedKeys() 
    Get an enumeration of the keys of the JSONObject. The keys will be sorted alphabetically.
 public static Object stringToValue(String s) 
    Try to convert a string into a number, boolean, or null. If the string can't be converted, return the string.
 static  void testValidity(Object o) throws JSONException 
    Throw an exception if the object is an NaN or infinite number.
 public JSONArray toJSONArray(JSONArray names) throws JSONException 
    Produce a JSONArray containing the values of the members of this JSONObject.
 public String toString() 
    Make a 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.

 public String toString(int indentFactor) throws JSONException 
    Make a prettyprinted JSON text of this JSONObject.

    Warning: This method assumes that the data structure is acyclical.

 String toString(int indentFactor,
    int indent) throws JSONException 
    Make a prettyprinted JSON text of this JSONObject.

    Warning: This method assumes that the data structure is acyclical.

 static String valueToString(Object value) throws JSONException 
    Make a JSON text of an Object value. If the object has an value.toJSONString() method, then that method will be used to produce the JSON text. The method is required to produce a strictly conforming text. If the object does not contain a toJSONString method (which is the most common case), then a text will be produced by other means. If the value is an array or Collection, then a JSONArray will be made from it and its toJSONString method will be called. If the value is a MAP, then a JSONObject will be made from it and its toJSONString method will be called. Otherwise, the value's toString method will be called, and the result will be quoted.

    Warning: This method assumes that the data structure is acyclical.

 static String valueToString(Object value,
    int indentFactor,
    int indent) throws JSONException 
    Make a prettyprinted JSON text of an object value.

    Warning: This method assumes that the data structure is acyclical.

 public Writer write(Writer writer) throws JSONException 
    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.