com.distributed.api
Class Clock

java.lang.Object
  |
  +--com.distributed.api.Clock

public class Clock

extends java.lang.Object

Clock Used to implement Vector Clock

Field Summary

static int	LAMPORT_CLOCK Constant used within the class
static int	NO_CLOCK Constant used within the class
static int	VECTOR_CLOCK Constant used within the class

Constructor Summary

Clock()
Default Constructor

Clock(Clock c)
Copy Constructor

Clock(int n, int id)
Constructor to be normally used by Environment

Clock(int n, int id, java.lang.String c)
Constructor to be normally used by Environment

Method Summary

int	compare(Clock c) Method to compare a clock with this object
static int	compare(Clock myClock, Clock hisClock) Method to compare two clocks
void	incrClock(Event e, Clock r) Method used to increment Clock
boolean	isComparable(Clock c) Method to see if this object and another clock are comparable or not
static boolean	isComparable(Clock myClock, Clock hisClock) Method to check if two clocks are comparable or not
int	lamportClock() Method to return value of Lamport's clock at this point
static int	lamportClock(java.lang.String c) methos to return Lamport Clock value from String
java.lang.String	toString(int convertion_type) Method to convert Clock into String

Methods inherited from class java.lang.Object

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

Field Detail

LAMPORT_CLOCK

public static final int LAMPORT_CLOCK

Constant used within the class

See Also:

Constant Field Values

NO_CLOCK

public static final int NO_CLOCK

Constant used within the class

See Also:

Constant Field Values

VECTOR_CLOCK

public static final int VECTOR_CLOCK

Constant used within the class

See Also:

Constant Field Values

Constructor Detail

Clock

public Clock()

Default Constructor

Clock

public Clock(Clock c)

Copy Constructor

Parameters:

c - The Clock to be Copied from

Clock

public Clock(int n,
             int id)
      throws java.lang.Exception

Constructor to be normally used by Environment

Parameters:

n - No. of Processes in system

id - Id of this process

Throws:

java.lang.Exception - Wrong Parameters

Clock

public Clock(int n,
             int id,
             java.lang.String c)
      throws java.lang.Exception

Constructor to be normally used by Environment

Parameters:

n - No. of Processes in system

id - Id of this process

c - Contains Clock vector in string form

Throws:

java.lang.Exception - Wrong Parameters

Method Detail

compare

public int compare(Clock c)

Method to compare a clock with this object

Parameters:

c - Object to be compared to

Returns:

1 if our clock < c, 2 if our clock > c, 0 if clocks incomparable

compare

public static int compare(Clock myClock,
                          Clock hisClock)

Method to compare two clocks

Parameters:

myClock - First Clock

hisClock - Second Clock

Returns:

1 if myClock < hisClock, 2 if myClock > hisClock, 0 if clocks incomparable

incrClock

public void incrClock(Event e,
                      Clock r)
               throws java.lang.Exception

Method used to increment Clock

Parameters:

e - Type of Event

r - Clock value if used to increment after receive event

Throws:

java.lang.Exception - On mismatch of any Parameters

isComparable

public boolean isComparable(Clock c)

Method to see if this object and another clock are comparable or not

Parameters:

c - Object to be check with

Returns:

True if comparable, False otherwise

isComparable

public static boolean isComparable(Clock myClock,
                                   Clock hisClock)

Method to check if two clocks are comparable or not

Parameters:

myClock - First Clock

hisClock - Second Clock

Returns:

True if comparable, False otherwise

lamportClock

public int lamportClock()

Method to return value of Lamport's clock at this point

Returns:

Value of Lamport Clock

lamportClock

public static int lamportClock(java.lang.String c)
                        throws java.lang.NumberFormatException

methos to return Lamport Clock value from String

Parameters:

c - Contains Clock value

Returns:

Lamport Clock Value from c

Throws:

java.lang.NumberFormatException - if unable to extract lamports clock

toString

public java.lang.String toString(int convertion_type)

Method to convert Clock into String

Returns:

String form of clock as specified by conversion_type