ostore.read
Class HeadPredicate

java.lang.Object
  |
  +--ostore.read.HeadPredicate

All Implemented Interfaces:

QuickSerializable, VersionPredicate

public class HeadPredicate

extends Object

implements VersionPredicate

A VersionPredicate that requires a version that was still the most recent version at some point in a specified range.

The class name comes from the CVS term "head".

Version:

$Id: HeadPredicate.java,v 1.19 2002/07/29 18:48:53 geels Exp $

Author:

Dennis Geels

Constructor Summary

HeadPredicate(InputBuffer buffer)
Constructs a HeadPredicate from its serialized form.

HeadPredicate(QSDate date)
Constructs a new HeadPredicate that requires the version that was the most recent version at a specific date.

HeadPredicate(QSDate low, QSDate high)
Constructs a new HeadPredicate that requires a version that was the most recent version at some date between low and high, inclusive.

Method Summary

QSDate	get_high() Returns the latest accaptable "head" date;
QSDate	get_low() Returns the earliest accaptable "head" date;
void	serialize(OutputBuffer buffer) Add the object to the buffer.
String	toString() Returns a human-readable representation of this predicate.

Methods inherited from class java.lang.Object

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

Constructor Detail

HeadPredicate

public HeadPredicate(QSDate low,
                     QSDate high)

Constructs a new HeadPredicate that requires a version that was the most recent version at some date between low and high, inclusive. Set high=Clock.QS_NEVER for open-ended predicates.

Parameters:

low - The earliest acceptable "head" date.

high - The latest acceptable "head" date.

See Also:

Clock.QS_NEVER

HeadPredicate

public HeadPredicate(QSDate date)

Constructs a new HeadPredicate that requires the version that was the most recent version at a specific date.

Parameters:

date - The time at which the desired version was head.

HeadPredicate

public HeadPredicate(InputBuffer buffer)
              throws QSException

Constructs a HeadPredicate from its serialized form.

Method Detail

get_low

public QSDate get_low()

Returns the earliest accaptable "head" date;

get_high

public QSDate get_high()

Returns the latest accaptable "head" date;

serialize

public void serialize(OutputBuffer buffer)

Description copied from interface: QuickSerializable

Add the object to the buffer.

Specified by:

serialize in interface QuickSerializable

Parameters:

buffer - the output buffer to add the object to

toString

public String toString()

Returns a human-readable representation of this predicate.

Overrides:

toString in class Object