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

Constructors

Constructor and Description
AbstractCounterGroup(String name, String displayName, Limits limits)

Method Summary

Methods

Modifier and Type	Method and Description
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