org.apache.hadoop.io

Class ArrayPrimitiveWritable

java.lang.Object

org.apache.hadoop.io.ArrayPrimitiveWritable

All Implemented Interfaces:

Writable

@InterfaceAudience.Public
@InterfaceStability.Stable
public class ArrayPrimitiveWritable
extends Object
implements Writable

This is a wrapper class. It wraps a Writable implementation around an array of primitives (e.g., int[], long[], etc.), with optimized wire format, and without creating new objects per element. This is a wrapper class only; it does not make a copy of the underlying array.

Constructor Summary

Constructors

Constructor and Description
ArrayPrimitiveWritable() Construct an empty instance, for use during Writable read
ArrayPrimitiveWritable(Class<?> componentType) Construct an instance of known type but no value yet for use with type-specific wrapper classes
ArrayPrimitiveWritable(Object value) Wrap an existing array of primitives

Method Summary

Methods

Modifier and Type	Method and Description
Object	get() Get the original array.
Class<?>	getComponentType()
Class<?>	getDeclaredComponentType()
boolean	isDeclaredComponentType(Class<?> componentType)
void	readFields(DataInput in) Deserialize the fields of this object from in.
void	set(Object value)
void	write(DataOutput out) Serialize the fields of this object to out.

Methods inherited from class java.lang.Object

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

Constructor Detail

ArrayPrimitiveWritable

public ArrayPrimitiveWritable()

Construct an empty instance, for use during Writable read

ArrayPrimitiveWritable

public ArrayPrimitiveWritable(Class<?> componentType)

Construct an instance of known type but no value yet for use with type-specific wrapper classes

ArrayPrimitiveWritable

public ArrayPrimitiveWritable(Object value)

Wrap an existing array of primitives

Parameters:

value - - array of primitives

Method Detail

get

public Object get()

Get the original array. Client must cast it back to type componentType[] (or may use type-specific wrapper classes).

Returns:

- original array as Object

getComponentType

public Class<?> getComponentType()

getDeclaredComponentType

public Class<?> getDeclaredComponentType()

isDeclaredComponentType

public boolean isDeclaredComponentType(Class<?> componentType)

set

public void set(Object value)

write

public void write(DataOutput out)
           throws IOException

Description copied from interface: Writable

Serialize the fields of this object to out.

Specified by:

write in interface Writable

Parameters:

out - DataOuput to serialize this object into.

Throws:

IOException

readFields

public void readFields(DataInput in)
                throws IOException

Description copied from interface: Writable

Deserialize the fields of this object from in.

For efficiency, implementations should attempt to re-use storage in the existing object where possible.

Specified by:

readFields in interface Writable

Parameters:

in - DataInput to deseriablize this object from.

Throws:

IOException