com.etymon.pjx
Class PdfNull

java.lang.Object
  com.etymon.pjx.PdfObject
      com.etymon.pjx.PdfNull

All Implemented Interfaces:

java.lang.Cloneable

public class PdfNull

extends PdfObject

Represents the PDF null object.

Field Summary

static PdfNull

NULL A PdfNull object representing the null value.

Constructor Summary

PdfNull()
Constructs a null object.

Method Summary

boolean	equals(java.lang.Object obj) Compares this instance with another PDF object for equality.
int	hashCode() Returns a hash code for this object.
static boolean	isNull(java.lang.Object obj) Checks whether an object represents a null value.
static PdfNull	valueOf() Returns a PdfNull object.

Methods inherited from class com.etymon.pjx.PdfObject

clone, filter, toString

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

Field Detail

NULL

public static final PdfNull NULL

A PdfNull object representing the null value.

Constructor Detail

PdfNull

public PdfNull()

Constructs a null object. In most cases there is no need to create a new instance of this class, and the valueOf() method is preferred.

Method Detail

isNull

public static boolean isNull(java.lang.Object obj)

Checks whether an object represents a null value. Note that this method differs slightly from equals(Object) in that this returns true when called with a null value. This method is useful for examining PDF objects, in which null and PdfNull should normally be considered equivalent. For example, if a dictionary value or an indirect object is PdfNull, it is equivalent to the object not existing.

Parameters:

obj - the object to examine.

Returns:

true if the object is either null or an instance of PdfNull; otherwise false is returned.

equals

public boolean equals(java.lang.Object obj)

Description copied from class: PdfObject

Compares this instance with another PDF object for equality.

Overrides:

equals in class PdfObject

Parameters:

obj - the object to compare this instance with.

Returns:

true if the PDF objects are equal.

hashCode

public int hashCode()

Description copied from class: PdfObject

Returns a hash code for this object.

Overrides:

hashCode in class PdfObject

Returns:

the hash code.

valueOf

public static PdfNull valueOf()

Returns a PdfNull object. This method is normally preferable to PdfNull() because it avoids allocating a new instance.

Returns:

the null object.