net.sf.json

Class JSONNull

java.lang.Object

net.sf.json.JSONNull

All Implemented Interfaces:

java.io.Serializable, JSON

public final class JSONNull
extends java.lang.Object
implements JSON

JSONNull is equivalent to the value that JavaScript calls null, whilst Java's null is equivalent to the value that JavaScript calls undefined.

Author:

JSON.org

See Also:

Serialized Form

Method Summary

Methods

Modifier and Type	Method and Description
boolean	equals(java.lang.Object object) A Null object is equal to the null value and to itself.
static JSONNull	getInstance() Returns the singleton instance of JSONNull
int	hashCode()
boolean	isArray() Returns true if this object is a JSONArray, false otherwise.
boolean	isEmpty() Returns true if this object has no elements or keys.
int	size() Returns the number of properties in an object or the size of the array.
java.lang.String	toString() Get the "null" string value.
java.lang.String	toString(int indentFactor) Make a prettyprinted JSON text.
java.lang.String	toString(int indentFactor, int indent) Make a prettyprinted JSON text.
java.io.Writer	write(java.io.Writer writer) Write the contents as JSON text to a writer.
java.io.Writer	writeCanonical(java.io.Writer w) Writes the canonicalized form of this JSON object.

Methods inherited from class java.lang.Object

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

Method Detail

getInstance

public static JSONNull getInstance()

Returns the singleton instance of JSONNull

equals

public boolean equals(java.lang.Object object)

A Null object is equal to the null value and to itself.

Overrides:

equals in class java.lang.Object

Parameters:

object - An object to test for nullness.

Returns:

true if the object parameter is the JSONObject.NULL object or null.

hashCode

public int hashCode()

Overrides:

hashCode in class java.lang.Object

isArray

public boolean isArray()

Description copied from interface: JSON

Returns true if this object is a JSONArray, false otherwise.

Specified by:

isArray in interface JSON

isEmpty

public boolean isEmpty()

Description copied from interface: JSON

Returns true if this object has no elements or keys.

Specified by:

isEmpty in interface JSON

size

public int size()

Description copied from interface: JSON

Returns the number of properties in an object or the size of the array.

Specified by:

size in interface JSON

Returns:

the size of an json object or array

toString

public java.lang.String toString()

Get the "null" string value.

Overrides:

toString in class java.lang.Object

Returns:

The string "null".

toString

public java.lang.String toString(int indentFactor)

Description copied from interface: JSON

Make a prettyprinted JSON text.

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

Specified by:

toString in interface JSON

Parameters:

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

Returns:

a printable, displayable, portable, transmittable representation of the object, beginning with { (left brace) and ending with } (right brace).

toString

public java.lang.String toString(int indentFactor,
                        int indent)

Description copied from interface: JSON

Make a prettyprinted JSON text.

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

Specified by:

toString in interface JSON

Parameters:

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

indent - The indentation of the top level.

Returns:

a printable, displayable, transmittable representation of the object, beginning with { (left brace) and ending with } (right brace).

write

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

Description copied from interface: JSON

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

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

Specified by:

write in interface JSON

Returns:

The writer.

Throws:

java.io.IOException

writeCanonical

public java.io.Writer writeCanonical(java.io.Writer w)
                              throws java.io.IOException

Description copied from interface: JSON

Writes the canonicalized form of this JSON object.

Specified by:

writeCanonical in interface JSON

Throws:

java.io.IOException