org.embulk.spi

Class Page

java.lang.Object

org.embulk.spi.Page

public abstract class Page
extends Object

An in-process (in-JVM) container of data records.

It serializes records to byte[] (in Buffer) for the following purposes.

• A) Avoid slowness by handling many Java Objects
• B) Avoid complexity by type-safe primitive arrays
• C) Track memory consumption by records
• D) Use off-heap memory

(C) and (D) may not be so meaningful as of Embulk v0.7+ (or since earlier) as recent Embulk unlikely allocates so many Pages at the same time. Recent Embulk is streaming-driven instead of multithreaded queue-based.

Page is NOT for inter-process communication. For multi-process execution such as the deprecated MapReduce Executor, the executor plugin takes responsibility about interoperable serialization.

Constructor Summary

Constructors

Constructor and Description
Page()

Method Summary

Modifier and Type	Method and Description
static Page	allocate(int length) Deprecated. It is to be removed, implemented only for compatibility. Plugins should no longer call it directly.
abstract Buffer	buffer()
abstract String	getStringReference(int index)
abstract List<String>	getStringReferences()
abstract org.msgpack.value.ImmutableValue	getValueReference(int index)
abstract List<org.msgpack.value.ImmutableValue>	getValueReferences()
abstract void	release()
abstract Page	setStringReferences(List<String> values)
abstract Page	setValueReferences(List<org.msgpack.value.ImmutableValue> values)
static Page	wrap(Buffer buffer) Deprecated. It is to be removed, implemented only for compatibility. Plugins should no longer call it directly.

Methods inherited from class java.lang.Object

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

Constructor Detail

Page

public Page()

Method Detail

setStringReferences

public abstract Page setStringReferences(List<String> values)

setValueReferences

public abstract Page setValueReferences(List<org.msgpack.value.ImmutableValue> values)

getStringReferences

public abstract List<String> getStringReferences()

getValueReferences

public abstract List<org.msgpack.value.ImmutableValue> getValueReferences()

getStringReference

public abstract String getStringReference(int index)

getValueReference

public abstract org.msgpack.value.ImmutableValue getValueReference(int index)

release

public abstract void release()

buffer

public abstract Buffer buffer()

allocate

@Deprecated
public static Page allocate(int length)

Deprecated. It is to be removed, implemented only for compatibility. Plugins should no longer call it directly.

Creates a new Page instance.

Parameters:

length - length of the internal Buffer of the created Page

Returns:

Page created

wrap

@Deprecated
public static Page wrap(Buffer buffer)

Deprecated. It is to be removed, implemented only for compatibility. Plugins should no longer call it directly.

Creates a new Page instance wrapping an internal Buffer.

Parameters:

buffer - the internal Buffer

Returns:

Page created