org.apache.hadoop.mapreduce
Class Counter

java.lang.Object
  org.apache.hadoop.mapreduce.Counter

All Implemented Interfaces:

Writable

Direct Known Subclasses:

Counters.Counter

public class Counter
extends Object
implements Writable

A named counter that tracks the progress of a map/reduce job.

Counters represent global counters, defined either by the Map-Reduce framework or applications. Each Counter is named by an Enum and has a long for the value.

Counters are bunched into Groups, each comprising of counters from a particular Enum class.

Constructor Summary

protected	Counter()
protected	Counter(String name, String displayName)

Method Summary

boolean	equals(Object genericRight)
String	getDisplayName() Get the name of the counter.
String	getName()
long	getValue() What is the current value of this counter?
int	hashCode()
void	increment(long incr) Increment this counter by the given value
void	readFields(DataInput in) Read the binary representation of the counter
protected void	setDisplayName(String displayName) Deprecated.
void	setValue(long value) Set this counter by the given value
void	write(DataOutput out) Write the binary representation of the counter

Methods inherited from class java.lang.Object

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

Constructor Detail

Counter

protected Counter()

Counter

protected Counter(String name,
                  String displayName)

Method Detail

setDisplayName

@Deprecated
protected void setDisplayName(String displayName)

Deprecated.

readFields

public void readFields(DataInput in)
                throws IOException

Read the binary representation of the counter

Specified by:

readFields in interface Writable

Parameters:

in - DataInput to deseriablize this object from.

Throws:

IOException

write

public void write(DataOutput out)
           throws IOException

Write the binary representation of the counter

Specified by:

write in interface Writable

Parameters:

out - DataOuput to serialize this object into.

Throws:

IOException

getName

public String getName()

getDisplayName

public String getDisplayName()

Get the name of the counter.

Returns:

the user facing name of the counter

getValue

public long getValue()

What is the current value of this counter?

Returns:

the current value

setValue

public void setValue(long value)

Set this counter by the given value

Parameters:

value - the value to set

increment

public void increment(long incr)

Increment this counter by the given value

Parameters:

incr - the value to increase this counter by

equals

public boolean equals(Object genericRight)

Overrides:

equals in class Object

hashCode

public int hashCode()

Overrides:

hashCode in class Object