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/*
* Copyright (c) 2002 JSON.org
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in all
* copies or substantial portions of the Software.
*
* The Software shall be used for Good, not Evil.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/
package com.amazonaws.util.json;
import java.io.IOException;
import java.io.Writer;
import java.lang.reflect.Field;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.lang.reflect.Modifier;
import java.util.Collection;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
import java.util.TreeSet;
/**
* 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:
*
* - An extra
, (comma) may appear just
* before the closing brace.
* - Strings may be quoted with
' (single
* quote).
* - Strings do not need to be quoted at all if they do not begin with a quote
* or single quote, and if they do not contain leading or trailing spaces,
* and if they do not contain any of these characters:
*
{ } [ ] / \ : , = ; # and if they do not look like numbers
* and if they are not the reserved words true,
* false, or null.
* - Keys can be followed by
= or => as well as
* by :.
* - Values can be followed by
; (semicolon) as
* well as by , (comma).
* - Numbers may have the
0x- (hex) prefix.
*
*
* @version 2010-05-17
*/
@SuppressWarnings({"rawtypes", "unchecked"})
public class JSONObject {
/**
* JSONObject.NULL is equivalent to the value that JavaScript calls null,
* whilst Java's null is equivalent to the value that JavaScript calls
* undefined.
*/
private static final class Null {
/**
* There is only intended to be a single instance of the NULL object,
* so the clone method returns itself.
* @return NULL.
*/
protected final Object clone() {
return this;
}
/**
* A Null object is equal to the null value and to itself. This breaks
* the contract for Object.equals(), but fixing it would be a
* potentially-breaking change so we can't do so until the next major
* version bump.
*
* @param object An object to test for nullness.
* @return true if the object parameter is the JSONObject.NULL object
* or null.
*/
public boolean equals(Object object) {
return object == null || object == this;
}
/**
* Make this explicit to appease findbugs until we can fix equals().
*
* @return a hash code value for this object.
*/
public int hashCode() {
return super.hashCode();
}
/**
* Get the "null" string value.
* @return The string "null".
*/
public String toString() {
return "null";
}
}
/**
* The map where the JSONObject's properties are kept.
*/
private Map map;
/**
* 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".
*/
public static final Object NULL = new Null();
/**
* Construct an empty JSONObject.
*/
public JSONObject() {
this.map = new HashMap();
}
/**
* 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.
* @param jo A JSONObject.
* @param names An array of strings.
* @throws JSONException
* @exception JSONException If a value is a non-finite number or if a name is duplicated.
*/
public JSONObject(JSONObject jo, String[] names) {
this();
for (int i = 0; i < names.length; i += 1) {
try {
putOnce(names[i], jo.opt(names[i]));
} catch (Exception ignore) {
}
}
}
/**
* Construct a JSONObject from a JSONTokener.
* @param 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(JSONTokener x) throws JSONException {
this();
char c;
String key;
if (x.nextClean() != '{') {
throw x.syntaxError("A JSONObject text must begin with '{'");
}
for (;;) {
c = x.nextClean();
switch (c) {
case 0:
throw x.syntaxError("A JSONObject text must end with '}'");
case '}':
return;
default:
x.back();
key = x.nextValue().toString();
}
/*
* The key is followed by ':'. We will also tolerate '=' or '=>'.
*/
c = x.nextClean();
if (c == '=') {
if (x.next() != '>') {
x.back();
}
} else if (c != ':') {
throw x.syntaxError("Expected a ':' after a key");
}
putOnce(key, x.nextValue());
/*
* Pairs are separated by ','. We will also tolerate ';'.
*/
switch (x.nextClean()) {
case ';':
case ',':
if (x.nextClean() == '}') {
return;
}
x.back();
break;
case '}':
return;
default:
throw x.syntaxError("Expected a ',' or '}'");
}
}
}
/**
* Construct a JSONObject from a Map.
*
* @param map A map object that can be used to initialize the contents of
* the JSONObject.
* @throws JSONException
*/
public JSONObject(Map map) {
this.map = new HashMap();
if (map != null) {
Iterator i = map.entrySet().iterator();
while (i.hasNext()) {
Map.Entry e = (Map.Entry)i.next();
this.map.put(e.getKey(), wrap(e.getValue()));
}
}
}
/**
* 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".
*
* @param bean An object that has getter methods that should be used
* to make a JSONObject.
*/
public JSONObject(Object bean) {
this();
populateMap(bean);
}
/**
* 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.
* @param object An object that has fields that should be used to make a
* JSONObject.
* @param names An array of strings, the names of the fields to be obtained
* from the object.
*/
public JSONObject(Object object, String names[]) {
this();
Class c = object.getClass();
for (int i = 0; i < names.length; i += 1) {
String name = names[i];
try {
putOpt(name, c.getField(name).get(object));
} catch (Exception ignore) {
}
}
}
/**
* Construct a JSONObject from a source JSON text string.
* This is the most commonly used JSONObject constructor.
* @param source A string beginning
* with { (left brace) and ending
* with } (right brace).
* @exception JSONException If there is a syntax error in the source
* string or a duplicated key.
*/
public JSONObject(String source) throws JSONException {
this(new JSONTokener(source));
}
/**
* 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.
* @param key A key string.
* @param value An object to be accumulated under the key.
* @return this.
* @throws JSONException If the value is an invalid number
* or if the key is null.
*/
public JSONObject accumulate(String key, Object value)
throws JSONException {
testValidity(value);
Object o = opt(key);
if (o == null) {
put(key, value instanceof JSONArray ?
new JSONArray().put(value) :
value);
} else if (o instanceof JSONArray) {
((JSONArray)o).put(value);
} else {
put(key, new JSONArray().put(o).put(value));
}
return this;
}
/**
* 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.
* @param key A key string.
* @param value An object to be accumulated under the key.
* @return this.
* @throws JSONException If the key is null or if the current value
* associated with the key is not a JSONArray.
*/
public JSONObject append(String key, Object value) throws JSONException {
testValidity(value);
Object o = opt(key);
if (o == null) {
put(key, new JSONArray().put(value));
} else if (o instanceof JSONArray) {
put(key, ((JSONArray)o).put(value));
} else {
throw new JSONException("JSONObject[" + key +
"] is not a JSONArray.");
}
return this;
}
/**
* Produce a string from a double. The string "null" will be returned if
* the number is not finite.
* @param d A double.
* @return A String.
*/
static public String doubleToString(double d) {
if (Double.isInfinite(d) || Double.isNaN(d)) {
return "null";
}
// Shave off trailing zeros and decimal point, if possible.
String s = Double.toString(d);
if (s.indexOf('.') > 0 && s.indexOf('e') < 0 && s.indexOf('E') < 0) {
while (s.endsWith("0")) {
s = s.substring(0, s.length() - 1);
}
if (s.endsWith(".")) {
s = s.substring(0, s.length() - 1);
}
}
return s;
}
/**
* Get the value object associated with a key.
*
* @param key A key string.
* @return The object associated with the key.
* @throws JSONException if the key is not found.
*/
public Object get(String key) throws JSONException {
Object o = opt(key);
if (o == null) {
throw new JSONException("JSONObject[" + quote(key) +
"] not found.");
}
return o;
}
/**
* Get the boolean value associated with a key.
*
* @param key A key string.
* @return The truth.
* @throws JSONException
* if the value is not a Boolean or the String "true" or "false".
*/
public boolean getBoolean(String key) throws JSONException {
Object o = get(key);
if (o.equals(Boolean.FALSE) ||
(o instanceof String &&
((String)o).equalsIgnoreCase("false"))) {
return false;
} else if (o.equals(Boolean.TRUE) ||
(o instanceof String &&
((String)o).equalsIgnoreCase("true"))) {
return true;
}
throw new JSONException("JSONObject[" + quote(key) +
"] is not a Boolean.");
}
/**
* Get the double value associated with a key.
* @param key A key string.
* @return The numeric value.
* @throws JSONException if the key is not found or
* if the value is not a Number object and cannot be converted to a number.
*/
public double getDouble(String key) throws JSONException {
Object o = get(key);
try {
return o instanceof Number ?
((Number)o).doubleValue() :
Double.valueOf((String)o).doubleValue();
} catch (Exception e) {
throw new JSONException("JSONObject[" + quote(key) +
"] is not a number.");
}
}
/**
* Get the int value associated with a key.
*
* @param key A key string.
* @return The integer value.
* @throws JSONException if the key is not found or if the value cannot
* be converted to an integer.
*/
public int getInt(String key) throws JSONException {
Object o = get(key);
try {
return o instanceof Number ?
((Number)o).intValue() :
Integer.parseInt((String)o);
} catch (Exception e) {
throw new JSONException("JSONObject[" + quote(key) +
"] is not an int.");
}
}
/**
* Get the JSONArray value associated with a key.
*
* @param key A key string.
* @return A JSONArray which is the value.
* @throws JSONException if the key is not found or
* if the value is not a JSONArray.
*/
public JSONArray getJSONArray(String key) throws JSONException {
Object o = get(key);
if (o instanceof JSONArray) {
return (JSONArray)o;
}
throw new JSONException("JSONObject[" + quote(key) +
"] is not a JSONArray.");
}
/**
* Get the JSONObject value associated with a key.
*
* @param key A key string.
* @return A JSONObject which is the value.
* @throws JSONException if the key is not found or
* if the value is not a JSONObject.
*/
public JSONObject getJSONObject(String key) throws JSONException {
Object o = get(key);
if (o instanceof JSONObject) {
return (JSONObject)o;
}
throw new JSONException("JSONObject[" + quote(key) +
"] is not a JSONObject.");
}
/**
* Get the long value associated with a key.
*
* @param key A key string.
* @return The long value.
* @throws JSONException if the key is not found or if the value cannot
* be converted to a long.
*/
public long getLong(String key) throws JSONException {
Object o = get(key);
try {
return o instanceof Number ?
((Number)o).longValue() :
Long.parseLong((String)o);
} catch (Exception e) {
throw new JSONException("JSONObject[" + quote(key) +
"] is not a long.");
}
}
/**
* Get an array of field names from a JSONObject.
*
* @return An array of field names, or null if there are no names.
*/
public static String[] getNames(JSONObject jo) {
int length = jo.length();
if (length == 0) {
return null;
}
Iterator i = jo.keys();
String[] names = new String[length];
int j = 0;
while (i.hasNext()) {
names[j] = (String)i.next();
j += 1;
}
return names;
}
/**
* Get an array of field names from an Object.
*
* @return An array of field names, or null if there are no names.
*/
public static String[] getNames(Object object) {
if (object == null) {
return null;
}
Class klass = object.getClass();
Field[] fields = klass.getFields();
int length = fields.length;
if (length == 0) {
return null;
}
String[] names = new String[length];
for (int i = 0; i < length; i += 1) {
names[i] = fields[i].getName();
}
return names;
}
/**
* Get the string associated with a key.
*
* @param key A key string.
* @return A string which is the value.
* @throws JSONException if the key is not found.
*/
public String getString(String key) throws JSONException {
return get(key).toString();
}
/**
* Tries to return the string associated with a key; or null if not found.
*/
public String tryGetString(String key) {
Object o = opt(key);
return o == null ? null : o.toString();
}
/**
* Determine if the JSONObject contains a specific key.
* @param key A key string.
* @return true if the key exists in the JSONObject.
*/
public boolean has(String key) {
return this.map.containsKey(key);
}
/**
* Increment a property of a JSONObject. If there is no such property,
* create one with a value of 1. If there is such a property, and if
* it is an Integer, Long, Double, or Float, then add one to it.
* @param key A key string.
* @return this.
* @throws JSONException If there is already a property with this name
* that is not an Integer, Long, Double, or Float.
*/
public JSONObject increment(String key) throws JSONException {
Object value = opt(key);
if (value == null) {
put(key, 1);
} else {
if (value instanceof Integer) {
put(key, ((Integer)value).intValue() + 1);
} else if (value instanceof Long) {
put(key, ((Long)value).longValue() + 1);
} else if (value instanceof Double) {
put(key, ((Double)value).doubleValue() + 1);
} else if (value instanceof Float) {
put(key, ((Float)value).floatValue() + 1);
} else {
throw new JSONException("Unable to increment [" + key + "].");
}
}
return this;
}
/**
* Determine if the value associated with the key is null or if there is
* no value.
* @param key A key string.
* @return true if there is no value associated with the key or if
* the value is the JSONObject.NULL object.
*/
public boolean isNull(String key) {
return JSONObject.NULL.equals(opt(key));
}
/**
* Get an enumeration of the keys of the JSONObject.
*
* @return An iterator of the keys.
*/
public Iterator keys() {
return this.map.keySet().iterator();
}
/**
* Get the number of keys stored in the JSONObject.
*
* @return The number of keys in the JSONObject.
*/
public int length() {
return this.map.size();
}
/**
* Produce a JSONArray containing the names of the elements of this
* JSONObject.
* @return A JSONArray containing the key strings, or null if the JSONObject
* is empty.
*/
public JSONArray names() {
JSONArray ja = new JSONArray();
Iterator keys = keys();
while (keys.hasNext()) {
ja.put(keys.next());
}
return ja.length() == 0 ? null : ja;
}
/**
* Produce a string from a Number.
* @param n A Number
* @return A String.
* @throws JSONException If n is a non-finite number.
*/
static public String numberToString(Number n)
throws JSONException {
if (n == null) {
throw new JSONException("Null pointer");
}
testValidity(n);
// Shave off trailing zeros and decimal point, if possible.
String s = n.toString();
if (s.indexOf('.') > 0 && s.indexOf('e') < 0 && s.indexOf('E') < 0) {
while (s.endsWith("0")) {
s = s.substring(0, s.length() - 1);
}
if (s.endsWith(".")) {
s = s.substring(0, s.length() - 1);
}
}
return s;
}
/**
* Get an optional value associated with a key.
* @param key A key string.
* @return An object which is the value, or null if there is no value.
*/
public Object opt(String key) {
return key == null ? null : this.map.get(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".
*
* @param key A key string.
* @return The truth.
*/
public boolean optBoolean(String key) {
return optBoolean(key, false);
}
/**
* 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).
*
* @param key A key string.
* @param defaultValue The default.
* @return The truth.
*/
public boolean optBoolean(String key, boolean defaultValue) {
try {
return getBoolean(key);
} catch (Exception e) {
return defaultValue;
}
}
/**
* 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.
*
* @param key A string which is the key.
* @return An object which is the value.
*/
public double optDouble(String key) {
return optDouble(key, Double.NaN);
}
/**
* 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.
*
* @param key A key string.
* @param defaultValue The default.
* @return An object which is the value.
*/
public double optDouble(String key, double defaultValue) {
try {
Object o = opt(key);
if (o instanceof Number) {
return ((Number) o).doubleValue();
} else {
return Double.parseDouble((String) o);
}
} catch (Exception e) {
return defaultValue;
}
}
/**
* 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.
*
* @param key A key string.
* @return An object which is the value.
*/
public int optInt(String key) {
return optInt(key, 0);
}
/**
* 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.
*
* @param key A key string.
* @param defaultValue The default.
* @return An object which is the value.
*/
public int optInt(String key, int defaultValue) {
try {
return getInt(key);
} catch (Exception e) {
return defaultValue;
}
}
/**
* 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.
*
* @param key A key string.
* @return A JSONArray which is the value.
*/
public JSONArray optJSONArray(String key) {
Object o = opt(key);
return o instanceof JSONArray ? (JSONArray)o : null;
}
/**
* 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.
*
* @param key A key string.
* @return A JSONObject which is the value.
*/
public JSONObject optJSONObject(String key) {
Object o = opt(key);
return o instanceof JSONObject ? (JSONObject)o : null;
}
/**
* 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.
*
* @param key A key string.
* @return An object which is the value.
*/
public long optLong(String key) {
return optLong(key, 0);
}
/**
* 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.
*
* @param key A key string.
* @param defaultValue The default.
* @return An object which is the value.
*/
public long optLong(String key, long defaultValue) {
try {
return getLong(key);
} catch (Exception e) {
return defaultValue;
}
}
/**
* 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.
*
* @param key A key string.
* @return A string which is the value.
*/
public String optString(String key) {
return optString(key, "");
}
/**
* Get an optional string associated with a key.
* It returns the defaultValue if there is no such key.
*
* @param key A key string.
* @param defaultValue The default.
* @return A string which is the value.
*/
public String optString(String key, String defaultValue) {
Object o = opt(key);
return o instanceof String ? o.toString() : defaultValue;
}
private void populateMap(Object bean) {
Class klass = bean.getClass();
// If klass is a System class then set includeSuperClass to false.
boolean includeSuperClass = klass.getClassLoader() != null;
Method[] methods = (includeSuperClass) ?
klass.getMethods() : klass.getDeclaredMethods();
for (int i = 0; i < methods.length; i += 1) {
try {
Method method = methods[i];
if (Modifier.isPublic(method.getModifiers())) {
String name = method.getName();
String key = "";
if (name.startsWith("get")) {
if (name.equals("getClass") ||
name.equals("getDeclaringClass")) {
key = "";
} else {
key = name.substring(3);
}
} else if (name.startsWith("is")) {
key = name.substring(2);
}
if (key.length() > 0 &&
Character.isUpperCase(key.charAt(0)) &&
method.getParameterTypes().length == 0) {
if (key.length() == 1) {
key = key.toLowerCase();
} else if (!Character.isUpperCase(key.charAt(1))) {
key = key.substring(0, 1).toLowerCase() +
key.substring(1);
}
Object result = method.invoke(bean, (Object[])null);
map.put(key, wrap(result));
}
}
} catch (IllegalAccessException ignore) {
} catch (InvocationTargetException ignore) {
} catch (RuntimeException ignore) {
// TODO: Should we at least be logging these somewhere?
}
}
}
/**
* Put a key/boolean pair in the JSONObject.
*
* @param key A key string.
* @param value A boolean which is the value.
* @return this.
* @throws JSONException If the key is null.
*/
public JSONObject put(String key, boolean value) throws JSONException {
put(key, value ? Boolean.TRUE : Boolean.FALSE);
return this;
}
/**
* Put a key/value pair in the JSONObject, where the value will be a
* JSONArray which is produced from a Collection.
* @param key A key string.
* @param value A Collection value.
* @return this.
* @throws JSONException
*/
public JSONObject put(String key, Collection value) throws JSONException {
put(key, new JSONArray(value));
return this;
}
/**
* Put a key/double pair in the JSONObject.
*
* @param key A key string.
* @param value A double which is the value.
* @return this.
* @throws JSONException If the key is null or if the number is invalid.
*/
public JSONObject put(String key, double value) throws JSONException {
put(key, Double.valueOf(value));
return this;
}
/**
* Put a key/int pair in the JSONObject.
*
* @param key A key string.
* @param value An int which is the value.
* @return this.
* @throws JSONException If the key is null.
*/
public JSONObject put(String key, int value) throws JSONException {
put(key, Integer.valueOf(value));
return this;
}
/**
* Put a key/long pair in the JSONObject.
*
* @param key A key string.
* @param value A long which is the value.
* @return this.
* @throws JSONException If the key is null.
*/
public JSONObject put(String key, long value) throws JSONException {
put(key, Long.valueOf(value));
return this;
}
/**
* Put a key/value pair in the JSONObject, where the value will be a
* JSONObject which is produced from a Map.
* @param key A key string.
* @param value A Map value.
* @return this.
* @throws JSONException
*/
public JSONObject put(String key, Map value) throws JSONException {
put(key, new JSONObject(value));
return this;
}
/**
* 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.
* @param key A key string.
* @param 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.
* @return this.
* @throws JSONException If the value is non-finite number
* or if the key is null.
*/
public JSONObject put(String key, Object value) throws JSONException {
if (key == null) {
throw new JSONException("Null key.");
}
if (value != null) {
testValidity(value);
this.map.put(key, value);
} else {
remove(key);
}
return this;
}
/**
* 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.
* @param key
* @param value
* @return his.
* @throws JSONException if the key is a duplicate
*/
public JSONObject putOnce(String key, Object value) throws JSONException {
if (key != null && value != null) {
if (opt(key) != null) {
throw new JSONException("Duplicate key \"" + key + "\"");
}
put(key, value);
}
return this;
}
/**
* Put a key/value pair in the JSONObject, but only if the
* key and the value are both non-null.
* @param key A key string.
* @param 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.
* @return this.
* @throws JSONException If the value is a non-finite number.
*/
public JSONObject putOpt(String key, Object value) throws JSONException {
if (key != null && value != null) {
put(key, value);
}
return this;
}
/**
* Produce a string in double quotes with backslash sequences in all the
* right places. A backslash will be inserted within = '\u0080' && c < '\u00a0')) {
t = "000" + Integer.toHexString(c);
sb.append("\\u" + t.substring(t.length() - 4));
} else {
sb.append(c);
}
}
}
sb.append('"');
return sb.toString();
}
/**
* Remove a name and its value, if present.
* @param key The name to be removed.
* @return The value that was associated with the name,
* or null if there was no value.
*/
public Object remove(String key) {
return this.map.remove(key);
}
/**
* Get an enumeration of the keys of the JSONObject.
* The keys will be sorted alphabetically.
*
* @return An iterator of the keys.
*/
public Iterator sortedKeys() {
return new TreeSet(this.map.keySet()).iterator();
}
/**
* Try to convert a string into a number, boolean, or null. If the string
* can't be converted, return the string.
* @param s A String.
* @return A simple JSON value.
*/
static public Object stringToValue(String s) {
if (s.equals("")) {
return s;
}
if (s.equalsIgnoreCase("true")) {
return Boolean.TRUE;
}
if (s.equalsIgnoreCase("false")) {
return Boolean.FALSE;
}
if (s.equalsIgnoreCase("null")) {
return JSONObject.NULL;
}
/*
* If it might be a number, try converting it.
* We support the non-standard 0x- convention.
* If a number cannot be produced, then the value will just
* be a string. Note that the 0x-, plus, and implied string
* conventions are non-standard. A JSON parser may accept
* non-JSON forms as long as it accepts all correct JSON forms.
*/
char b = s.charAt(0);
if ((b >= '0' && b <= '9') || b == '.' || b == '-' || b == '+') {
if (b == '0' && s.length() > 2 &&
(s.charAt(1) == 'x' || s.charAt(1) == 'X')) {
try {
return Integer.valueOf(s.substring(2), 16);
} catch (Exception ignore) {
}
}
try {
if (s.indexOf('.') > -1 ||
s.indexOf('e') > -1 || s.indexOf('E') > -1) {
return Double.valueOf(s);
} else {
Long myLong = Long.valueOf(s);
if (myLong.longValue() == myLong.intValue()) {
return Integer.valueOf(myLong.intValue());
} else {
return myLong;
}
}
} catch (Exception ignore) {
}
}
return s;
}
/**
* Throw an exception if the object is an NaN or infinite number.
* @param o The object to test.
* @throws JSONException If o is a non-finite number.
*/
static void testValidity(Object o) throws JSONException {
if (o != null) {
if (o instanceof Double) {
if (((Double)o).isInfinite() || ((Double)o).isNaN()) {
throw new JSONException(
"JSON does not allow non-finite numbers.");
}
} else if (o instanceof Float) {
if (((Float)o).isInfinite() || ((Float)o).isNaN()) {
throw new JSONException(
"JSON does not allow non-finite numbers.");
}
}
}
}
/**
* Produce a JSONArray containing the values of the members of this
* JSONObject.
* @param names A JSONArray containing a list of key strings. This
* determines the sequence of the values in the result.
* @return A JSONArray of values.
* @throws JSONException If any of the values are non-finite numbers.
*/
public JSONArray toJSONArray(JSONArray names) throws JSONException {
if (names == null || names.length() == 0) {
return null;
}
JSONArray ja = new JSONArray();
for (int i = 0; i < names.length(); i += 1) {
ja.put(this.opt(names.getString(i)));
}
return ja;
}
/**
* 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.
*
* @return a printable, displayable, portable, transmittable
* representation of the object, beginning
* with { (left brace) and ending
* with } (right brace).
*/
public String toString() {
try {
Iterator keys = keys();
StringBuffer sb = new StringBuffer("{");
while (keys.hasNext()) {
if (sb.length() > 1) {
sb.append(',');
}
Object o = keys.next();
sb.append(quote(o.toString()));
sb.append(':');
sb.append(valueToString(this.map.get(o)));
}
sb.append('}');
return sb.toString();
} catch (Exception e) {
return null;
}
}
/**
* Make a prettyprinted JSON text of this JSONObject.
*
* Warning: This method assumes that the data structure is acyclical.
* @param indentFactor The number of spaces to add to each level of
* indentation.
* @return a printable, displayable, portable, transmittable
* representation of the object, beginning
* with { (left brace) and ending
* with } (right brace).
* @throws JSONException If the object contains an invalid number.
*/
public String toString(int indentFactor) throws JSONException {
return toString(indentFactor, 0);
}
/**
* Make a prettyprinted JSON text of this JSONObject.
*
* Warning: This method assumes that the data structure is acyclical.
* @param indentFactor The number of spaces to add to each level of
* indentation.
* @param indent The indentation of the top level.
* @return a printable, displayable, transmittable
* representation of the object, beginning
* with { (left brace) and ending
* with } (right brace).
* @throws JSONException If the object contains an invalid number.
*/
String toString(int indentFactor, int indent) throws JSONException {
int j;
int n = length();
if (n == 0) {
return "{}";
}
Iterator keys = sortedKeys();
StringBuffer sb = new StringBuffer("{");
int newindent = indent + indentFactor;
Object o;
if (n == 1) {
o = keys.next();
sb.append(quote(o.toString()));
sb.append(": ");
sb.append(valueToString(this.map.get(o), indentFactor,
indent));
} else {
while (keys.hasNext()) {
o = keys.next();
if (sb.length() > 1) {
sb.append(",\n");
} else {
sb.append('\n');
}
for (j = 0; j < newindent; j += 1) {
sb.append(' ');
}
sb.append(quote(o.toString()));
sb.append(": ");
sb.append(valueToString(this.map.get(o), indentFactor,
newindent));
}
if (sb.length() > 1) {
sb.append('\n');
for (j = 0; j < indent; j += 1) {
sb.append(' ');
}
}
}
sb.append('}');
return sb.toString();
}
/**
* 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.
* @param value The value to be serialized.
* @return a printable, displayable, transmittable
* representation of the object, beginning
* with { (left brace) and ending
* with } (right brace).
* @throws JSONException If the value is or contains an invalid number.
*/
static String valueToString(Object value) throws JSONException {
if (value == null || value.equals(NULL)) {
return "null";
}
if (value instanceof Number) {
return numberToString((Number) value);
}
if (value instanceof Boolean || value instanceof JSONObject ||
value instanceof JSONArray) {
return value.toString();
}
if (value instanceof Map) {
return new JSONObject((Map)value).toString();
}
if (value instanceof Collection) {
return new JSONArray((Collection)value).toString();
}
if (value.getClass().isArray()) {
return new JSONArray(value).toString();
}
return quote(value.toString());
}
/**
* Make a prettyprinted JSON text of an object value.
*
* Warning: This method assumes that the data structure is acyclical.
* @param value The value to be serialized.
* @param indentFactor The number of spaces to add to each level of
* indentation.
* @param indent The indentation of the top level.
* @return a printable, displayable, transmittable
* representation of the object, beginning
* with { (left brace) and ending
* with } (right brace).
* @throws JSONException If the object contains an invalid number.
*/
static String valueToString(Object value, int indentFactor, int indent)
throws JSONException {
if (value == null || value.equals(NULL)) {
return "null";
}
if (value instanceof Number) {
return numberToString((Number) value);
}
if (value instanceof Boolean) {
return value.toString();
}
if (value instanceof JSONObject) {
return ((JSONObject)value).toString(indentFactor, indent);
}
if (value instanceof JSONArray) {
return ((JSONArray)value).toString(indentFactor, indent);
}
if (value instanceof Map) {
return new JSONObject((Map)value).toString(indentFactor, indent);
}
if (value instanceof Collection) {
return new JSONArray((Collection)value).toString(indentFactor, indent);
}
if (value.getClass().isArray()) {
return new JSONArray(value).toString(indentFactor, indent);
}
return quote(value.toString());
}
/**
* Wrap an object, if necessary. If the object is null, return the NULL
* object. If it is an array or collection, wrap it in a JSONArray. If
* it is a map, wrap it in a JSONObject. If it is a standard property
* (Double, String, et al) then it is already wrapped. Otherwise, if it
* comes from one of the java packages, turn it into a string. And if
* it doesn't, try to wrap it in a JSONObject. If the wrapping fails,
* then null is returned.
*
* @param object The object to wrap
* @return The wrapped value
*/
static Object wrap(Object object) {
try {
if (object == null) {
return NULL;
}
if (object instanceof JSONObject || object instanceof JSONArray ||
NULL.equals(object) || object instanceof String ||
object instanceof Byte || object instanceof Character ||
object instanceof Short || object instanceof Integer ||
object instanceof Long || object instanceof Boolean ||
object instanceof Float || object instanceof Double) {
return object;
}
if (object instanceof Collection) {
return new JSONArray((Collection)object);
}
if (object.getClass().isArray()) {
return new JSONArray(object);
}
if (object instanceof Map) {
return new JSONObject((Map)object);
}
Package objectPackage = object.getClass().getPackage();
String objectPackageName = ( objectPackage != null ? objectPackage.getName() : "" );
if (objectPackageName.startsWith("java.") ||
objectPackageName.startsWith("javax.") ||
object.getClass().getClassLoader() == null) {
return object.toString();
}
return new JSONObject(object);
} catch(Exception exception) {
return null;
}
}
/**
* 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.
*
* @return The writer.
* @throws JSONException
*/
public Writer write(Writer writer) throws JSONException {
try {
boolean b = false;
Iterator keys = keys();
writer.write('{');
while (keys.hasNext()) {
if (b) {
writer.write(',');
}
Object k = keys.next();
writer.write(quote(k.toString()));
writer.write(':');
Object v = this.map.get(k);
if (v instanceof JSONObject) {
((JSONObject)v).write(writer);
} else if (v instanceof JSONArray) {
((JSONArray)v).write(writer);
} else {
writer.write(valueToString(v));
}
b = true;
}
writer.write('}');
return writer;
} catch (IOException exception) {
throw new JSONException(exception);
}
}
}