org.apache.pig.impl.util.avro

Class AvroBagWrapper<T>

java.lang.Object

org.apache.pig.impl.util.avro.AvroBagWrapper<T>

Type Parameters:

T - Type of objects in Avro array

All Implemented Interfaces:

java.io.Serializable, java.lang.Comparable, java.lang.Iterable<Tuple>, org.apache.hadoop.io.Writable, org.apache.hadoop.io.WritableComparable, DataBag, Spillable

public final class AvroBagWrapper<T>
extends java.lang.Object
implements DataBag

Class that implements the Pig bag interface, wrapping an Avro array. Designed to reduce data copying.

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
AvroBagWrapper(org.apache.avro.generic.GenericArray<T> a) Create new AvroBagWrapper instance.

Method Summary

Methods

Modifier and Type	Method and Description
void	add(Tuple t) Add a tuple to the bag.
void	addAll(DataBag b) Add contents of a bag to the bag.
void	clear() Clear out the contents of the bag, both on disk and in memory.
int	compareTo(java.lang.Object o)
long	getMemorySize() Requests that an object return an estimate of its in memory size.
boolean	isDistinct() Find out if the bag is distinct.
boolean	isSorted() Find out if the bag is sorted.
java.util.Iterator<Tuple>	iterator() Get an iterator to the bag.
void	markStale(boolean stale) This is used by FuncEvalSpec.FakeDataBag.
void	readFields(java.io.DataInput d)
long	size() Get the number of elements in the bag, both in memory and on disk.
long	spill() Instructs an object to spill whatever it can to disk and release references to any data structures it spills.
void	write(java.io.DataOutput d)

Methods inherited from class java.lang.Object

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

Constructor Detail

AvroBagWrapper

public AvroBagWrapper(org.apache.avro.generic.GenericArray<T> a)

Create new AvroBagWrapper instance.

Parameters:

a - Avro array to wrap in bag

Method Detail

spill

public long spill()

Description copied from interface: Spillable

Instructs an object to spill whatever it can to disk and release references to any data structures it spills.

Specified by:

spill in interface Spillable

Returns:

number of objects spilled.

getMemorySize

public long getMemorySize()

Description copied from interface: Spillable

Requests that an object return an estimate of its in memory size.

Specified by:

getMemorySize in interface Spillable

Returns:

estimated in memory size.

readFields

public void readFields(java.io.DataInput d)
                throws java.io.IOException

Specified by:

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

Throws:

java.io.IOException

write

public void write(java.io.DataOutput d)
           throws java.io.IOException

Specified by:

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

Throws:

java.io.IOException

compareTo

public int compareTo(java.lang.Object o)

Specified by:

compareTo in interface java.lang.Comparable

size

public long size()

Description copied from interface: DataBag

Get the number of elements in the bag, both in memory and on disk.

Specified by:

size in interface DataBag

Returns:

number of elements in the bag

isSorted

public boolean isSorted()

Description copied from interface: DataBag

Find out if the bag is sorted.

Specified by:

isSorted in interface DataBag

Returns:

true if this is a sorted data bag, false otherwise.

isDistinct

public boolean isDistinct()

Description copied from interface: DataBag

Find out if the bag is distinct.

Specified by:

isDistinct in interface DataBag

Returns:

true if the bag is a distinct bag, false otherwise.

iterator

public java.util.Iterator<Tuple> iterator()

Description copied from interface: DataBag

Get an iterator to the bag. For default and distinct bags, no particular order is guaranteed. For sorted bags the order is guaranteed to be sorted according to the provided comparator.

Specified by:

iterator in interface java.lang.Iterable<Tuple>

Specified by:

iterator in interface DataBag

Returns:

tuple iterator

add

public void add(Tuple t)

Description copied from interface: DataBag

Add a tuple to the bag.

Specified by:

add in interface DataBag

Parameters:

t - tuple to add.

addAll

public void addAll(DataBag b)

Description copied from interface: DataBag

Add contents of a bag to the bag.

Specified by:

addAll in interface DataBag

Parameters:

b - bag to add contents of.

clear

public void clear()

Description copied from interface: DataBag

Clear out the contents of the bag, both on disk and in memory. Any attempts to read after this is called will produce undefined results.

Specified by:

clear in interface DataBag

markStale

public void markStale(boolean stale)

Description copied from interface: DataBag

This is used by FuncEvalSpec.FakeDataBag.

Specified by:

markStale in interface DataBag

Parameters:

stale - Set stale state.