com.db4o.internal

Class Null

java.lang.Object

com.db4o.internal.Null

All Implemented Interfaces:

PreparedComparison, Comparable4, Indexable4, LinkLengthAware

public class Null
extends java.lang.Object
implements Indexable4, PreparedComparison

Field Summary

Fields

Modifier and Type	Field and Description
static Null	INSTANCE

Method Summary

Methods

Modifier and Type	Method and Description
int	compareTo(java.lang.Object a_obj) return a negative int, zero or a positive int if the object being held in 'this' is smaller, equal or greater than the passed object. Typical implementation: return this.object - obj;
void	defragIndexEntry(DefragmentContextImpl context)
int	linkLength()
PreparedComparison	prepareComparison(Context context, java.lang.Object obj_) creates a prepared comparison to compare multiple objects against one single object.
java.lang.Object	readIndexEntry(Context context, ByteArrayBuffer a_reader)
void	writeIndexEntry(Context context, ByteArrayBuffer a_writer, java.lang.Object a_object)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

INSTANCE

public static final Null INSTANCE

Method Detail

compareTo

public int compareTo(java.lang.Object a_obj)

Description copied from interface: PreparedComparison

return a negative int, zero or a positive int if the object being held in 'this' is smaller, equal or greater than the passed object.

Typical implementation: return this.object - obj;

Specified by:

compareTo in interface PreparedComparison

linkLength

public int linkLength()

Specified by:

linkLength in interface LinkLengthAware

readIndexEntry

public java.lang.Object readIndexEntry(Context context,
                              ByteArrayBuffer a_reader)

Specified by:

readIndexEntry in interface Indexable4

writeIndexEntry

public void writeIndexEntry(Context context,
                   ByteArrayBuffer a_writer,
                   java.lang.Object a_object)

Specified by:

writeIndexEntry in interface Indexable4

defragIndexEntry

public void defragIndexEntry(DefragmentContextImpl context)

Specified by:

defragIndexEntry in interface Indexable4

prepareComparison

public PreparedComparison prepareComparison(Context context,
                                   java.lang.Object obj_)

Description copied from interface: Comparable4

creates a prepared comparison to compare multiple objects against one single object.

Specified by:

prepareComparison in interface Comparable4

Parameters:

context - the context of the comparison

obj_ - the object that is to be compared against multiple other objects

Returns:

the prepared comparison