com.ibm.tspaces.examples.handler
Class StaleTuple

java.lang.Object
  |
  +--com.ibm.tspaces.SuperTuple
        |
        +--com.ibm.tspaces.SubclassableTuple
              |
              +--com.ibm.tspaces.examples.handler.StaleTuple

public class StaleTuple

extends SubclassableTuple

A StaleTuple is an ordered sequence of Fields where the first field is a TimeToDie timestamp that is stored at the time that the Tuple is written. This first field is hidden from the application.

For the purposes of this example the 2nd field is a string and and is indexed. The 3rd field is also a String but is not indexed. Other applications would define these differently.

Author:

Pete Wyckoff, John Thomas

See Also:

Tuple, SuperTuple, Field, TupleSpace, Serialized Form

Constructor Summary

StaleTuple()
constructor with no arguments builds a template tuple

StaleTuple(StaleTimestamp timestamp)
constructor with StaleTimestamp specified.

StaleTuple(java.lang.String key)
constructor with one String argument builds a template tuple to do simple match retrieve based on Field2

StaleTuple(java.lang.String key, java.lang.String data)
constructor just calls the super tuple constructor

Method Summary

java.lang.String	getData() This method will return the data Field from the tuple.
java.lang.String	getKey() This method will return the key Field from the tuple.
void	setData(java.lang.String data) This method will set the data Field from the tuple.
void	setKey(java.lang.String key) This method will set the Key Field from the tuple.
void	setTimeToLive(long time) Sets the time to live value
void	updateExpirationDate() Sets the first Field to the date/time stanp when the object is elgible for deletion.

Methods inherited from class com.ibm.tspaces.SuperTuple

add, add, add, add, add, add, add, add, add, add, add, add, add, add, add, addFieldType, changeName, clone, equals, fieldExists, fields, getExpire, getField, getField, getFieldType, getTimeStamp, getTupleID, isExpired, matches, numberOfFields, putField, setExpire, setField, setFields, setFormal, setFormal, setFormal, setFormal, setName, setTimeStamp, setTupleID, setType, setType, setValue, setValue, structureName, template, toString

Methods inherited from class java.lang.Object

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

Constructor Detail

StaleTuple

public StaleTuple()
           throws TupleSpaceException

constructor with no arguments builds a template tuple

StaleTuple

public StaleTuple(StaleTimestamp timestamp)
           throws TupleSpaceException

constructor with StaleTimestamp specified. It will return a template with the timestamp specified

StaleTuple

public StaleTuple(java.lang.String key)
           throws TupleSpaceException

constructor with one String argument builds a template tuple to do simple match retrieve based on Field2

StaleTuple

public StaleTuple(java.lang.String key,
                  java.lang.String data)
           throws TupleSpaceException

constructor just calls the super tuple constructor

Parameters:

obj1 - an object that will be in a field

obj2 - an object that will be in a field

Method Detail

getData

public java.lang.String getData()
                         throws TupleSpaceException

This method will return the data Field from the tuple.

Returns:

String that contains the "Data" field from Tuple

setData

public void setData(java.lang.String data)
             throws TupleSpaceException

This method will set the data Field from the tuple.

Parameters:

data - String that should be placed in the "Data" field of Tuple

getKey

public java.lang.String getKey()
                        throws TupleSpaceException

This method will return the key Field from the tuple.

Returns:

String that contains the "Key" field from Tuple

setKey

public void setKey(java.lang.String key)
            throws TupleSpaceException

This method will set the Key Field from the tuple.

Parameters:

key - String that should be placed in the "Key" field of Tuple

setTimeToLive

public void setTimeToLive(long time)

Sets the time to live value

Parameters:

timetolive - The time in MS that should expire before the Tuple is elgible for deletion..

updateExpirationDate

public void updateExpirationDate()
                          throws TupleSpaceException

Sets the first Field to the date/time stanp when the object is elgible for deletion.

This method is used by the StaleTupleSpaceHandler to update field 0 when the Write command is invoked in the server.