Package org.apache.beam.runners.dataflow.util

Class RandomAccessData.RandomAccessDataCoder

java.lang.Object

org.apache.beam.sdk.coders.Coder<RandomAccessData>

org.apache.beam.sdk.coders.StructuredCoder<RandomAccessData>

org.apache.beam.sdk.coders.AtomicCoder<RandomAccessData>

org.apache.beam.runners.dataflow.util.RandomAccessData.RandomAccessDataCoder

All Implemented Interfaces:

Serializable

Enclosing class:

RandomAccessData

public static class RandomAccessData.RandomAccessDataCoder
extends AtomicCoder<RandomAccessData>

A Coder which encodes the valid parts of this stream. This follows the same encoding scheme as ByteArrayCoder. This coder is deterministic and consistent with equals.

This coder does not support encoding positive infinity.

See Also:

• Serialized Form

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.beam.sdk.coders.Coder

Coder.Context, Coder.NonDeterministicException

Constructor Summary

Constructors

Constructor	Description
RandomAccessDataCoder()

Method Summary

Modifier and Type	Method	Description
boolean	consistentWithEquals()	Returns true if this Coder is injective with respect to Object.equals(java.lang.Object).
RandomAccessData	decode(InputStream inStream)	Decodes a value of type T from the given input stream in the given context.
RandomAccessData	decode(InputStream inStream, Coder.Context context)	Decodes a value of type T from the given input stream in the given context.
void	encode(RandomAccessData value, OutputStream outStream)	Encodes the given value of type T onto the given output stream.
void	encode(RandomAccessData value, OutputStream outStream, Coder.Context context)	Encodes the given value of type T onto the given output stream in the given context.
protected long	getEncodedElementByteSize(RandomAccessData value)	Returns the size in bytes of the encoded value using this coder.
boolean	isRegisterByteSizeObserverCheap(RandomAccessData value)	Returns whether Coder.registerByteSizeObserver(T, org.apache.beam.sdk.util.common.ElementByteSizeObserver) cheap enough to call for every element, that is, if this Coder can calculate the byte size of the element to be coded in roughly constant time (or lazily).
static RandomAccessData.RandomAccessDataCoder	of()
void	verifyDeterministic()	Throw Coder.NonDeterministicException if the coding is not deterministic.

Methods inherited from class org.apache.beam.sdk.coders.AtomicCoder

equals, getCoderArguments, getComponents, hashCode

Methods inherited from class org.apache.beam.sdk.coders.StructuredCoder

toString

Methods inherited from class org.apache.beam.sdk.coders.Coder

getEncodedElementByteSizeUsingCoder, getEncodedTypeDescriptor, registerByteSizeObserver, structuralValue, verifyDeterministic, verifyDeterministic

Methods inherited from class java.lang.Object

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

Constructor Details

RandomAccessDataCoder

public RandomAccessDataCoder()

Method Details

of

public static RandomAccessData.RandomAccessDataCoder of()

encode

public void encode(RandomAccessData value,
 OutputStream outStream)
            throws CoderException,
IOException

Description copied from class: Coder

Encodes the given value of type T onto the given output stream. Multiple elements can be encoded next to each other on the output stream, each coder should encode information to know how many bytes to read when decoding. A common approach is to prefix the encoding with the element's encoded length.

Specified by:

encode in class Coder<RandomAccessData>

Throws:

CoderException - if the value could not be encoded for some reason

IOException - if writing to the OutputStream fails for some reason

encode

public void encode(RandomAccessData value,
 OutputStream outStream,
 Coder.Context context)
            throws CoderException,
IOException

Description copied from class: Coder

Encodes the given value of type T onto the given output stream in the given context.

Overrides:

encode in class Coder<RandomAccessData>

Throws:

CoderException - if the value could not be encoded for some reason

IOException - if writing to the OutputStream fails for some reason

decode

public RandomAccessData decode(InputStream inStream)
                        throws CoderException,
IOException

Description copied from class: Coder

Decodes a value of type T from the given input stream in the given context. Returns the decoded value. Multiple elements can be encoded next to each other on the input stream, each coder should encode information to know how many bytes to read when decoding. A common approach is to prefix the encoding with the element's encoded length.

Specified by:

decode in class Coder<RandomAccessData>

Throws:

CoderException - if the value could not be decoded for some reason

IOException - if reading from the InputStream fails for some reason

decode

public RandomAccessData decode(InputStream inStream,
 Coder.Context context)
                        throws CoderException,
IOException

Description copied from class: Coder

Decodes a value of type T from the given input stream in the given context. Returns the decoded value.

Overrides:

decode in class Coder<RandomAccessData>

Throws:

CoderException - if the value could not be decoded for some reason

IOException - if reading from the InputStream fails for some reason

verifyDeterministic

public void verifyDeterministic()

Description copied from class: AtomicCoder

Throw Coder.NonDeterministicException if the coding is not deterministic.

In order for a Coder to be considered deterministic, the following must be true:

• two values that compare as equal (via Object.equals() or Comparable.compareTo(), if supported) have the same encoding.
• the Coder always produces a canonical encoding, which is the same for an instance of an object even if produced on different computers at different times.

.

Unless overridden, does not throw. An AtomicCoder is presumed to be deterministic

Overrides:

verifyDeterministic in class AtomicCoder<RandomAccessData>

consistentWithEquals

public boolean consistentWithEquals()

Description copied from class: Coder

Returns true if this Coder is injective with respect to Object.equals(java.lang.Object).

Whenever the encoded bytes of two values are equal, then the original values are equal according to Objects.equals(). Note that this is well-defined for null.

This condition is most notably false for arrays. More generally, this condition is false whenever equals() compares object identity, rather than performing a semantic/structural comparison.

By default, returns false.

Overrides:

consistentWithEquals in class Coder<RandomAccessData>

isRegisterByteSizeObserverCheap

public boolean isRegisterByteSizeObserverCheap(RandomAccessData value)

Description copied from class: Coder

Returns whether Coder.registerByteSizeObserver(T, org.apache.beam.sdk.util.common.ElementByteSizeObserver) cheap enough to call for every element, that is, if this Coder can calculate the byte size of the element to be coded in roughly constant time (or lazily).

Not intended to be called by user code, but instead by PipelineRunner implementations.

By default, returns false. The default Coder.registerByteSizeObserver(T, org.apache.beam.sdk.util.common.ElementByteSizeObserver) implementation invokes Coder.getEncodedElementByteSize(T) which requires re-encoding an element unless it is overridden. This is considered expensive.

Overrides:

isRegisterByteSizeObserverCheap in class Coder<RandomAccessData>

getEncodedElementByteSize

protected long getEncodedElementByteSize(RandomAccessData value)
                                  throws Exception

Description copied from class: Coder

Returns the size in bytes of the encoded value using this coder.

Overrides:

getEncodedElementByteSize in class Coder<RandomAccessData>

Throws:

Exception