org.apache.hadoop.mapreduce.counters
Class AbstractCounterGroup<T extends Counter>

java.lang.Object
  org.apache.hadoop.mapreduce.counters.AbstractCounterGroup<T>

Type Parameters:

T - type of the counter for the group

All Implemented Interfaces:

Iterable<T>, org.apache.hadoop.io.Writable, CounterGroupBase<T>

@InterfaceAudience.Private
public abstract class AbstractCounterGroup<T extends Counter>
extends Object
implements CounterGroupBase<T>

An abstract class to provide common implementation of the generic counter group in both mapred and mapreduce package.

Constructor Summary

AbstractCounterGroup(String name, String displayName, Limits limits)

Method Summary

T	addCounter(String counterName, String displayName, long value) Add a counter to this group
void	addCounter(T counter) Add a counter to this group.
boolean	equals(Object genericRight)
T	findCounter(String counterName) Find a counter in the group.
T	findCounter(String counterName, boolean create) Find a counter in the group
T	findCounter(String counterName, String displayName) Find a counter in the group.
String	getDisplayName() Get the display name of the group.
String	getName() Get the internal name of the group
int	hashCode()
void	incrAllCounters(CounterGroupBase<T> rightGroup) Increment all counters by a group of counters
Iterator<T>	iterator()
protected abstract T	newCounter() Abstract factory method to create a new counter of type T
protected abstract T	newCounter(String counterName, String displayName, long value) Abstract factory method to create a new counter of type T
void	readFields(DataInput in)
void	setDisplayName(String displayName) Set the display name of the group
int	size()
void	write(DataOutput out) GenericGroup ::= displayName #counter counter*

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.hadoop.mapreduce.counters.CounterGroupBase

getUnderlyingGroup

Constructor Detail

AbstractCounterGroup

public AbstractCounterGroup(String name,
                            String displayName,
                            Limits limits)

Method Detail

getName

public String getName()

Description copied from interface: CounterGroupBase

Get the internal name of the group

Specified by:

getName in interface CounterGroupBase<T extends Counter>

Returns:

the internal name

getDisplayName

public String getDisplayName()

Description copied from interface: CounterGroupBase

Get the display name of the group.

Specified by:

getDisplayName in interface CounterGroupBase<T extends Counter>

Returns:

the human readable name

setDisplayName

public void setDisplayName(String displayName)

Description copied from interface: CounterGroupBase

Set the display name of the group

Specified by:

setDisplayName in interface CounterGroupBase<T extends Counter>

Parameters:

displayName - of the group

addCounter

public void addCounter(T counter)

Description copied from interface: CounterGroupBase

Add a counter to this group.

Specified by:

addCounter in interface CounterGroupBase<T extends Counter>

Parameters:

counter - to add

addCounter

public T addCounter(String counterName,
                    String displayName,
                    long value)

Description copied from interface: CounterGroupBase

Add a counter to this group

Specified by:

addCounter in interface CounterGroupBase<T extends Counter>

Parameters:

counterName - of the counter

displayName - of the counter

value - of the counter

Returns:

the counter

findCounter

public T findCounter(String counterName,
                     String displayName)

Description copied from interface: CounterGroupBase

Find a counter in the group.

Specified by:

findCounter in interface CounterGroupBase<T extends Counter>

Parameters:

counterName - the name of the counter

displayName - the display name of the counter

Returns:

the counter that was found or added

findCounter

public T findCounter(String counterName,
                     boolean create)

Description copied from interface: CounterGroupBase

Find a counter in the group

Specified by:

findCounter in interface CounterGroupBase<T extends Counter>

Parameters:

counterName - the name of the counter

create - create the counter if not found if true

Returns:

the counter that was found or added or null if create is false

findCounter

public T findCounter(String counterName)

Description copied from interface: CounterGroupBase

Find a counter in the group.

Specified by:

findCounter in interface CounterGroupBase<T extends Counter>

Parameters:

counterName - the name of the counter

Returns:

the counter that was found or added

newCounter

protected abstract T newCounter(String counterName,
                                String displayName,
                                long value)

Abstract factory method to create a new counter of type T

Parameters:

counterName - of the counter

displayName - of the counter

value - of the counter

Returns:

a new counter

newCounter

protected abstract T newCounter()

Abstract factory method to create a new counter of type T

Returns:

a new counter object

iterator

public Iterator<T> iterator()

Specified by:

iterator in interface Iterable<T extends Counter>

write

public void write(DataOutput out)
           throws IOException

GenericGroup ::= displayName #counter counter*

Specified by:

write in interface org.apache.hadoop.io.Writable

Throws:

IOException

readFields

public void readFields(DataInput in)
                throws IOException

Specified by:

readFields in interface org.apache.hadoop.io.Writable

Throws:

IOException

size

public int size()

Specified by:

size in interface CounterGroupBase<T extends Counter>

Returns:

the number of counters in this group.

equals

public boolean equals(Object genericRight)

Overrides:

equals in class Object

hashCode

public int hashCode()

Overrides:

hashCode in class Object

incrAllCounters

public void incrAllCounters(CounterGroupBase<T> rightGroup)

Description copied from interface: CounterGroupBase

Increment all counters by a group of counters

Specified by:

incrAllCounters in interface CounterGroupBase<T extends Counter>

Parameters:

rightGroup - the group to be added to this group