atg.taglib.json.util
Class JSONArray

java.lang.Object
  atg.taglib.json.util.JSONArray

All Implemented Interfaces:

java.io.Serializable, java.lang.Cloneable, java.lang.Iterable, java.util.Collection, java.util.List, java.util.RandomAccess

public class JSONArray
extends java.lang.Object
implements java.util.List, java.util.RandomAccess, java.lang.Cloneable, java.io.Serializable

A JSONArray is an ordered sequence of values. Its external text form is a string wrapped in square brackets with commas separating the values. The internal form is an object having get and opt methods for accessing the values by index, and put methods for adding or replacing values. The values can be any of these types: Boolean, JSONArray, JSONObject, Number, String, or the JSONObject.NULL object.

The constructor can convert a JSON text into a Java object. The toString method converts to JSON text.

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 coersion for you.

The texts produced by the toString methods strictly conform to JSON syntax rules. The constructors are more forgiving in the texts they will accept:

• An extra , (comma) may appear just before the closing bracket.
• The null value will be inserted when there is , (comma) elision.
• 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.
• Values can be separated by ; (semicolon) as well as by , (comma).
• Numbers may have the 0- (octal) or 0x- (hex) prefix.
• Comments written in the slashshlash, slashstar, and hash conventions will be ignored.

Version:

2

Author:

JSON.org

See Also:

Serialized Form

Constructor Summary

JSONArray()
Construct an empty JSONArray.

JSONArray(java.util.Collection collection)
Construct a JSONArray from a Collection.

JSONArray(JSONTokener x)
Construct a JSONArray from a JSONTokener.

JSONArray(java.lang.Object[] array)
Construct a JSONArray from a Java Array

JSONArray(java.lang.String string)
Construct a JSONArray from a source sJSON text.

Method Summary

void	add(int index, java.lang.Object element)
boolean	add(java.lang.Object o)
boolean	addAll(java.util.Collection c)
boolean	addAll(int index, java.util.Collection c)
void	clear()
java.lang.Object	clone()
boolean	contains(java.lang.Object o)
boolean	containsAll(java.util.Collection c)
boolean	equals(java.lang.Object object) Returns true if this JSONArray is equal to the one passed in.
java.lang.Object	get(int index) Get the object value associated with an index.
boolean	getBoolean(int index) Get the boolean value associated with an index.
double	getDouble(int index) Get the double value associated with an index.
int	getInt(int index) Get the int value associated with an index.
JSONArray	getJSONArray(int index) Get the JSONArray associated with an index.
JSONObject	getJSONObject(int index) Get the JSONObject associated with an index.
long	getLong(int index) Get the long value associated with an index.
java.lang.String	getString(int index) Get the string associated with an index.
int	hashCode() Return a hashCode for the JSONArray.
int	indexOf(java.lang.Object o)
boolean	isEmpty()
boolean	isNull(int index) Determine if the value is null.
java.util.Iterator	iterator()
java.lang.String	join(java.lang.String separator) Make a string from the contents of this JSONArray.
int	lastIndexOf(java.lang.Object o)
int	length() Get the number of elements in the JSONArray, included nulls.
java.util.ListIterator	listIterator()
java.util.ListIterator	listIterator(int index)
java.lang.Object	opt(int index) Get the optional object value associated with an index.
boolean	optBoolean(int index) Get the optional boolean value associated with an index.
boolean	optBoolean(int index, boolean defaultValue) Get the optional boolean value associated with an index.
double	optDouble(int index) Get the optional double value associated with an index.
double	optDouble(int index, double defaultValue) Get the optional double value associated with an index.
int	optInt(int index) Get the optional int value associated with an index.
int	optInt(int index, int defaultValue) Get the optional int value associated with an index.
JSONArray	optJSONArray(int index) Get the optional JSONArray associated with an index.
JSONObject	optJSONObject(int index) Get the optional JSONObject associated with an index.
long	optLong(int index) Get the optional long value associated with an index.
long	optLong(int index, long defaultValue) Get the optional long value associated with an index.
java.lang.String	optString(int index) Get the optional string value associated with an index.
java.lang.String	optString(int index, java.lang.String defaultValue) Get the optional string associated with an index.
JSONArray	put(boolean value) Append a boolean value.
JSONArray	put(double value) Append a double value.
JSONArray	put(int value) Append an int value.
JSONArray	put(int index, boolean value) Put or replace a boolean value in the JSONArray.
JSONArray	put(int index, double value) Put or replace a double value.
JSONArray	put(int index, int value) Put or replace an int value.
JSONArray	put(int index, long value) Put or replace a long value.
JSONArray	put(int index, java.lang.Object value) Put or replace an object value in the JSONArray.
JSONArray	put(long value) Append an long value.
JSONArray	put(java.lang.Object value) Append an object value.
java.lang.Object	remove(int index)
boolean	remove(java.lang.Object o)
boolean	removeAll(java.util.Collection c)
boolean	retainAll(java.util.Collection c)
java.lang.Object	set(int index, java.lang.Object element)
int	size()
java.util.List	subList(int fromIndex, int toIndex)
java.lang.Object[]	toArray()
java.lang.Object[]	toArray(java.lang.Object[] a)
JSONObject	toJSONObject(JSONArray names) Produce a JSONObject by combining a JSONArray of names with the values of this JSONArray.
java.lang.String	toString() Make an JSON text of this JSONArray.
java.lang.String	toString(int indentFactor) Make a prettyprinted JSON text of this JSONArray.
java.io.Writer	write(java.io.Writer writer) Write the contents of the JSONArray as JSON text to a writer.

Methods inherited from class java.lang.Object

finalize, getClass, notify, notifyAll, wait, wait, wait

Constructor Detail

JSONArray

public JSONArray()

Construct an empty JSONArray.

JSONArray

public JSONArray(JSONTokener x)
          throws JSONException

Construct a JSONArray from a JSONTokener.

Parameters:

x - A JSONTokener

Throws:

JSONException - If there is a syntax error.

JSONArray

public JSONArray(java.lang.String string)
          throws JSONException

Construct a JSONArray from a source sJSON text.

Parameters:

string - A string that begins with [ (left bracket) and ends with ] (right bracket).

Throws:

JSONException - If there is a syntax error.

JSONArray

public JSONArray(java.util.Collection collection)

Construct a JSONArray from a Collection.

Parameters:

collection - A Collection.

JSONArray

public JSONArray(java.lang.Object[] array)

Construct a JSONArray from a Java Array

Parameters:

array - an Array

Method Detail

get

public java.lang.Object get(int index)

Get the object value associated with an index.

Specified by:

get in interface java.util.List

Parameters:

index - The index must be between 0 and length() - 1.

Returns:

An object value.

Throws:

java.lang.IndexOutOfBoundsException - If there is no value for the index.

getBoolean

public boolean getBoolean(int index)
                   throws JSONException

Get the boolean value associated with an index. The string values "true" and "false" are converted to boolean.

Parameters:

index - The index must be between 0 and length() - 1.

Returns:

The truth.

Throws:

JSONException - If there is no value for the index or if the value is not convertable to boolean.

getDouble

public double getDouble(int index)
                 throws JSONException

Get the double value associated with an index.

Parameters:

index - The index must be between 0 and length() - 1.

Returns:

The value.

Throws:

JSONException - If the key is not found or if the value cannot be converted to a number.

getInt

public int getInt(int index)
           throws JSONException

Get the int value associated with an index.

Parameters:

index - The index must be between 0 and length() - 1.

Returns:

The value.

Throws:

JSONException - If the key is not found or if the value cannot be converted to a number. if the value cannot be converted to a number.

getJSONArray

public JSONArray getJSONArray(int index)
                       throws JSONException

Get the JSONArray associated with an index.

Parameters:

index - The index must be between 0 and length() - 1.

Returns:

A JSONArray value.

Throws:

JSONException - If there is no value for the index. or if the value is not a JSONArray

getJSONObject

public JSONObject getJSONObject(int index)
                         throws JSONException

Get the JSONObject associated with an index.

Parameters:

index - subscript

Returns:

A JSONObject value.

Throws:

JSONException - If there is no value for the index or if the value is not a JSONObject

getLong

public long getLong(int index)
             throws JSONException

Get the long value associated with an index.

Parameters:

index - The index must be between 0 and length() - 1.

Returns:

The value.

Throws:

JSONException - If the key is not found or if the value cannot be converted to a number.

getString

public java.lang.String getString(int index)
                           throws JSONException

Get the string associated with an index.

Parameters:

index - The index must be between 0 and length() - 1.

Returns:

A string value.

Throws:

JSONException - If there is no value for the index.

isNull

public boolean isNull(int index)

Determine if the value is null.

Parameters:

index - The index must be between 0 and length() - 1.

Returns:

true if the value at the index is null, or if there is no value.

join

public java.lang.String join(java.lang.String separator)
                      throws JSONException

Make a string from the contents of this JSONArray. The separator string is inserted between each element. Warning: This method assumes that the data structure is acyclical.

Parameters:

separator - A string that will be inserted between the elements.

Returns:

a string.

Throws:

JSONException - If the array contains an invalid number.

length

public int length()

Get the number of elements in the JSONArray, included nulls.

Returns:

The length (or size).

opt

public java.lang.Object opt(int index)

Get the optional object value associated with an index.

Parameters:

index - The index must be between 0 and length() - 1.

Returns:

An object value, or null if there is no object at that index.

optBoolean

public boolean optBoolean(int index)

Get the optional boolean value associated with an index. It returns false if there is no value at that index, or if the value is not Boolean.TRUE or the String "true".

Parameters:

index - The index must be between 0 and length() - 1.

Returns:

The truth.

optBoolean

public boolean optBoolean(int index,
                          boolean defaultValue)

Get the optional boolean value associated with an index. It returns the defaultValue if there is no value at that index or if it is not a Boolean or the String "true" or "false" (case insensitive).

Parameters:

index - The index must be between 0 and length() - 1.

defaultValue - A boolean default.

Returns:

The truth.

optDouble

public double optDouble(int index)

Get the optional double value associated with an index. NaN is returned if there is no value for the index, or if the value is not a number and cannot be converted to a number.

Parameters:

index - The index must be between 0 and length() - 1.

Returns:

The value.

optDouble

public double optDouble(int index,
                        double defaultValue)

Get the optional double value associated with an index. The defaultValue is returned if there is no value for the index, or if the value is not a number and cannot be converted to a number.

Parameters:

index - subscript

defaultValue - The default value.

Returns:

The value.

optInt

public int optInt(int index)

Get the optional int value associated with an index. Zero is returned if there is no value for the index, or if the value is not a number and cannot be converted to a number.

Parameters:

index - The index must be between 0 and length() - 1.

Returns:

The value.

optInt

public int optInt(int index,
                  int defaultValue)

Get the optional int value associated with an index. The defaultValue is returned if there is no value for the index, or if the value is not a number and cannot be converted to a number.

Parameters:

index - The index must be between 0 and length() - 1.

defaultValue - The default value.

Returns:

The value.

optJSONArray

public JSONArray optJSONArray(int index)

Get the optional JSONArray associated with an index.

Parameters:

index - subscript

Returns:

A JSONArray value, or null if the index has no value, or if the value is not a JSONArray.

optJSONObject

public JSONObject optJSONObject(int index)

Get the optional JSONObject associated with an index. Null is returned if the key is not found, or null if the index has no value, or if the value is not a JSONObject.

Parameters:

index - The index must be between 0 and length() - 1.

Returns:

A JSONObject value.

optLong

public long optLong(int index)

Get the optional long value associated with an index. Zero is returned if there is no value for the index, or if the value is not a number and cannot be converted to a number.

Parameters:

index - The index must be between 0 and length() - 1.

Returns:

The value.

optLong

public long optLong(int index,
                    long defaultValue)

Get the optional long value associated with an index. The defaultValue is returned if there is no value for the index, or if the value is not a number and cannot be converted to a number.

Parameters:

index - The index must be between 0 and length() - 1.

defaultValue - The default value.

Returns:

The value.

optString

public java.lang.String optString(int index)

Get the optional string value associated with an index. It returns an empty string if there is no value at that index. If the value is not a string and is not null, then it is coverted to a string.

Parameters:

index - The index must be between 0 and length() - 1.

Returns:

A String value.

optString

public java.lang.String optString(int index,
                                  java.lang.String defaultValue)

Get the optional string associated with an index. The defaultValue is returned if the key is not found.

Parameters:

index - The index must be between 0 and length() - 1.

defaultValue - The default value.

Returns:

A String value.

put

public JSONArray put(boolean value)

Append a boolean value. This increases the array's length by one.

Parameters:

value - A boolean value.

Returns:

this

put

public JSONArray put(double value)
              throws JSONException

Append a double value. This increases the array's length by one.

Parameters:

value - A double value.

Returns:

this.

Throws:

JSONException - if the value is not finite.

put

public JSONArray put(int value)

Append an int value. This increases the array's length by one.

Parameters:

value - An int value.

Returns:

this.

put

public JSONArray put(long value)

Append an long value. This increases the array's length by one.

Parameters:

value - A long value.

Returns:

this.

put

public JSONArray put(java.lang.Object value)

Append an object value. This increases the array's length by one.

Parameters:

value - An object value. The value should be a Boolean, Double, Integer, JSONArray, JSObject, Long, or String, or the JSONObject.NULL object.

Returns:

this.

put

public JSONArray put(int index,
                     boolean value)
              throws JSONException

Put or replace a boolean value in the JSONArray. If the index is greater than the length of the JSONArray, then null elements will be added as necessary to pad it out.

Parameters:

index - The subscript.

value - A boolean value.

Returns:

this.

Throws:

JSONException - If the index is negative.

put

public JSONArray put(int index,
                     double value)
              throws JSONException

Put or replace a double value. If the index is greater than the length of the JSONArray, then null elements will be added as necessary to pad it out.

Parameters:

index - The subscript.

value - A double value.

Returns:

this.

Throws:

JSONException - If the index is negative or if the value is not finite.

put

public JSONArray put(int index,
                     int value)
              throws JSONException

Put or replace an int value. If the index is greater than the length of the JSONArray, then null elements will be added as necessary to pad it out.

Parameters:

index - The subscript.

value - An int value.

Returns:

this.

Throws:

JSONException - If the index is negative.

put

public JSONArray put(int index,
                     long value)
              throws JSONException

Put or replace a long value. If the index is greater than the length of the JSONArray, then null elements will be added as necessary to pad it out.

Parameters:

index - The subscript.

value - A long value.

Returns:

this.

Throws:

JSONException - If the index is negative.

put

public JSONArray put(int index,
                     java.lang.Object value)
              throws JSONException

Put or replace an object value in the JSONArray. If the index is greater than the length of the JSONArray, then null elements will be added as necessary to pad it out.

Parameters:

index - The subscript.

value - The value to put into the array.

Returns:

this.

Throws:

JSONException - If the index is negative or if the the value is an invalid number.

toJSONObject

public JSONObject toJSONObject(JSONArray names)
                        throws JSONException

Produce a JSONObject by combining a JSONArray of names with the values of this JSONArray.

Parameters:

names - A JSONArray containing a list of key strings. These will be paired with the values.

Returns:

A JSONObject, or null if there are no names or if this JSONArray has no values.

Throws:

JSONException - If any of the names are null.

toString

public java.lang.String toString()

Make an JSON text of this JSONArray. For compactness, no unnecessary whitespace is added. If it is not possible to produce a syntactically correct JSON text then null will be returned instead. This could occur if the array contains an invalid number.

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

Overrides:

toString in class java.lang.Object

Returns:

a printable, displayable, transmittable representation of the array.

toString

public java.lang.String toString(int indentFactor)
                          throws JSONException

Make a prettyprinted JSON text of this JSONArray. Warning: This method assumes that the data structure is acyclical.

Parameters:

indentFactor - The number of spaces to add to each level of indentation.

Returns:

a printable, displayable, transmittable representation of the object, beginning with [ (left bracket) and ending with ] (right bracket).

Throws:

JSONException

write

public java.io.Writer write(java.io.Writer writer)
                     throws JSONException

Write the contents of the JSONArray as JSON text to a writer. For compactness, no whitespace is added.

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

Returns:

The writer.

Throws:

JSONException

add

public boolean add(java.lang.Object o)

Specified by:

add in interface java.util.Collection

Specified by:

add in interface java.util.List

add

public void add(int index,
                java.lang.Object element)

Specified by:

add in interface java.util.List

addAll

public boolean addAll(java.util.Collection c)

Specified by:

addAll in interface java.util.Collection

Specified by:

addAll in interface java.util.List

addAll

public boolean addAll(int index,
                      java.util.Collection c)

Specified by:

addAll in interface java.util.List

clear

public void clear()

Specified by:

clear in interface java.util.Collection

Specified by:

clear in interface java.util.List

contains

public boolean contains(java.lang.Object o)

Specified by:

contains in interface java.util.Collection

Specified by:

contains in interface java.util.List

containsAll

public boolean containsAll(java.util.Collection c)

Specified by:

containsAll in interface java.util.Collection

Specified by:

containsAll in interface java.util.List

indexOf

public int indexOf(java.lang.Object o)

Specified by:

indexOf in interface java.util.List

isEmpty

public boolean isEmpty()

Specified by:

isEmpty in interface java.util.Collection

Specified by:

isEmpty in interface java.util.List

iterator

public java.util.Iterator iterator()

Specified by:

iterator in interface java.lang.Iterable

Specified by:

iterator in interface java.util.Collection

Specified by:

iterator in interface java.util.List

lastIndexOf

public int lastIndexOf(java.lang.Object o)

Specified by:

lastIndexOf in interface java.util.List

listIterator

public java.util.ListIterator listIterator()

Specified by:

listIterator in interface java.util.List

listIterator

public java.util.ListIterator listIterator(int index)

Specified by:

listIterator in interface java.util.List

remove

public boolean remove(java.lang.Object o)

Specified by:

remove in interface java.util.Collection

Specified by:

remove in interface java.util.List

remove

public java.lang.Object remove(int index)

Specified by:

remove in interface java.util.List

removeAll

public boolean removeAll(java.util.Collection c)

Specified by:

removeAll in interface java.util.Collection

Specified by:

removeAll in interface java.util.List

retainAll

public boolean retainAll(java.util.Collection c)

Specified by:

retainAll in interface java.util.Collection

Specified by:

retainAll in interface java.util.List

set

public java.lang.Object set(int index,
                            java.lang.Object element)

Specified by:

set in interface java.util.List

size

public int size()

Specified by:

size in interface java.util.Collection

Specified by:

size in interface java.util.List

subList

public java.util.List subList(int fromIndex,
                              int toIndex)

Specified by:

subList in interface java.util.List

toArray

public java.lang.Object[] toArray()

Specified by:

toArray in interface java.util.Collection

Specified by:

toArray in interface java.util.List

toArray

public java.lang.Object[] toArray(java.lang.Object[] a)

Specified by:

toArray in interface java.util.Collection

Specified by:

toArray in interface java.util.List

clone

public java.lang.Object clone()

Overrides:

clone in class java.lang.Object

equals

public boolean equals(java.lang.Object object)

Returns true if this JSONArray is equal to the one passed in. The two arrays are considered equal if both arrays contain the same number of elements, and all corresponding pairs of elements in the two arrays are equal.

Specified by:

equals in interface java.util.Collection

Specified by:

equals in interface java.util.List

Overrides:

equals in class java.lang.Object

Parameters:

object - The JSONArray to compare against

Returns:

true if the two arrays are equal

See Also:

Object.equals(java.lang.Object)

hashCode

public int hashCode()

Return a hashCode for the JSONArray. This returns the hashcode for the underlying Object[] that stores the array elements

Specified by:

hashCode in interface java.util.Collection

Specified by:

hashCode in interface java.util.List

Overrides:

hashCode in class java.lang.Object

Returns:

a hash code value for this JSONArray.

See Also:

Object.hashCode()