Package org.apache.hadoop.util

Class SequentialNumber

java.lang.Object

org.apache.hadoop.util.SequentialNumber

All Implemented Interfaces:

IdGenerator

@Private
public abstract class SequentialNumber
extends Object
implements IdGenerator

Sequential number generator. This class is thread safe.

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	SequentialNumber(long initialValue)	Create a new instance with the given initial value.

Method Summary

Modifier and Type	Method	Description
boolean	equals(Object that)
long	getCurrentValue()
int	hashCode()
long	nextValue()	Increment and then return the next value.
void	setCurrentValue(long value)	Set current value.
boolean	setIfGreater(long value)
void	skipTo(long newValue)	Skip to the new value.

Methods inherited from class java.lang.Object

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

Constructor Details

SequentialNumber

protected SequentialNumber(long initialValue)

Create a new instance with the given initial value.

Parameters:

initialValue - initialValue.

Method Details

getCurrentValue

public long getCurrentValue()

Returns:

the current value.

setCurrentValue

public void setCurrentValue(long value)

Set current value.

Parameters:

value - value.

setIfGreater

public boolean setIfGreater(long value)

nextValue

public long nextValue()

Increment and then return the next value.

Specified by:

nextValue in interface IdGenerator

Returns:

long value.

skipTo

public void skipTo(long newValue)
            throws IllegalStateException

Skip to the new value.

Parameters:

newValue - newValue.

Throws:

IllegalStateException - Cannot skip to less than the current value.

equals

public boolean equals(Object that)

Overrides:

equals in class Object

hashCode

public int hashCode()

Overrides:

hashCode in class Object