org.apache.beam.sdk.coders

Class SnappyCoder<T>

java.lang.Object

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

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

org.apache.beam.sdk.coders.SnappyCoder<T>

All Implemented Interfaces:

java.io.Serializable

public class SnappyCoder<T>
extends StructuredCoder<T>

Wraps an existing coder with Snappy compression. It makes sense to use this coder only when it's likely that the encoded value is quite large and compressible.

See Also:

Serialized Form

Nested Class Summary

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

Coder.Context, Coder.NonDeterministicException

Method Summary

Modifier and Type	Method and Description
T	decode(java.io.InputStream is) Decodes a value of type T from the given input stream in the given context.
void	encode(T value, java.io.OutputStream os) Encodes the given value of type T onto the given output stream.
java.util.List<? extends Coder<?>>	getCoderArguments() If this is a Coder for a parameterized type, returns the list of Coders being used for each of the parameters in the same order they appear within the parameterized type's type signature.
static <T> SnappyCoder<T>	of(Coder<T> innerCoder) Wraps the given coder into a SnappyCoder.
void	verifyDeterministic() Throw Coder.NonDeterministicException if the coding is not deterministic.

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

equals, getComponents, hashCode, toString

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

consistentWithEquals, decode, encode, getEncodedElementByteSize, getEncodedTypeDescriptor, isRegisterByteSizeObserverCheap, registerByteSizeObserver, structuralValue, verifyDeterministic, verifyDeterministic

Methods inherited from class java.lang.Object

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

Method Detail

of

public static <T> SnappyCoder<T> of(Coder<T> innerCoder)

Wraps the given coder into a SnappyCoder.

encode

public void encode(T value,
                   java.io.OutputStream os)
            throws java.io.IOException

Description copied from class: Coder

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

Specified by:

encode in class Coder<T>

Throws:

java.io.IOException - if writing to the OutputStream fails for some reason

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

decode

public T decode(java.io.InputStream is)
         throws java.io.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.

Specified by:

decode in class Coder<T>

Throws:

java.io.IOException - if reading from the InputStream fails for some reason

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

getCoderArguments

public java.util.List<? extends Coder<?>> getCoderArguments()

Description copied from class: Coder

If this is a Coder for a parameterized type, returns the list of Coders being used for each of the parameters in the same order they appear within the parameterized type's type signature. If this cannot be done, or this Coder does not encode/decode a parameterized type, returns the empty list.

Specified by:

getCoderArguments in class Coder<T>

verifyDeterministic

public void verifyDeterministic()
                         throws Coder.NonDeterministicException

Description copied from class: Coder

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.

Specified by:

verifyDeterministic in class Coder<T>

Throws:

Coder.NonDeterministicException - if this coder is not deterministic.