org.apache.beam.sdk.coders

Class ByteArrayCoder

java.lang.Object

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

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

org.apache.beam.sdk.coders.AtomicCoder<byte[]>

org.apache.beam.sdk.coders.ByteArrayCoder

All Implemented Interfaces:

Serializable, Coder<byte[]>

public class ByteArrayCoder
extends AtomicCoder<byte[]>

A Coder for byte[].

The encoding format is as follows:

• If in a non-nested context (the byte[] is the only value in the stream), the bytes are read/written directly.
• If in a nested context, the bytes are prefixed with the length of the array, encoded via a VarIntCoder.

See Also:

Serialized Form

Nested Class Summary

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

Coder.Context, Coder.NonDeterministicException

Method Summary

Modifier and Type	Method and Description
byte[]	decode(InputStream inStream, Coder.Context context) Decodes a value of type T from the given input stream in the given context.
void	encode(byte[] value, OutputStream outStream, Coder.Context context) Encodes the given value of type T onto the given output stream in the given context.
void	encodeAndOwn(byte[] value, OutputStream outStream, Coder.Context context) Encodes the provided value with the identical encoding to encode(byte[], java.io.OutputStream, org.apache.beam.sdk.coders.Coder.Context), but with optimizations that take ownership of the value.
protected long	getEncodedElementByteSize(byte[] value, Coder.Context context) Returns the size in bytes of the encoded value using this coder.
boolean	isRegisterByteSizeObserverCheap(byte[] value, Coder.Context context) Returns whether Coder.registerByteSizeObserver(T, org.apache.beam.sdk.util.common.ElementByteSizeObserver, org.apache.beam.sdk.coders.Coder.Context) 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 ByteArrayCoder	of()
Object	structuralValue(byte[] value) Returns an object with an Object.equals() method that represents structural equality on the argument.

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

getCoderArguments, getInstanceComponents

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

verifyDeterministic

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

asCloudObject, consistentWithEquals, equals, getAllowedEncodings, getComponents, getEncodingId, hashCode, registerByteSizeObserver, toString, verifyDeterministic, verifyDeterministic

Methods inherited from class java.lang.Object

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

Method Detail

of

public static ByteArrayCoder of()

encode

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

Description copied from interface: Coder

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

Throws:

IOException - if writing to the OutputStream fails for some reason

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

encodeAndOwn

public void encodeAndOwn(byte[] value,
                         OutputStream outStream,
                         Coder.Context context)
                  throws IOException,
                         CoderException

Encodes the provided value with the identical encoding to encode(byte[], java.io.OutputStream, org.apache.beam.sdk.coders.Coder.Context), but with optimizations that take ownership of the value.

Once passed to this method, value should never be observed or mutated again.

Throws:

IOException

CoderException

decode

public byte[] decode(InputStream inStream,
                     Coder.Context context)
              throws IOException,
                     CoderException

Description copied from interface: Coder

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

Throws:

IOException - if reading from the InputStream fails for some reason

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

structuralValue

public Object structuralValue(byte[] value)

Returns an object with an Object.equals() method that represents structural equality on the argument.

For any two values x and y of type T, if their encoded bytes are the same, then it must be the case that structuralValue(x).equals(@code structuralValue(y).

Most notably:

• The structural value for an array coder should perform a structural comparison of the contents of the arrays, rather than the default behavior of comparing according to object identity.
• The structural value for a coder accepting null should be a proper object with an equals() method, even if the input value is null.

See also Coder.consistentWithEquals().

Specified by:

structuralValue in interface Coder<byte[]>

Overrides:

structuralValue in class StandardCoder<byte[]>

Returns:

objects that are equal if the two arrays contain the same bytes.

isRegisterByteSizeObserverCheap

public boolean isRegisterByteSizeObserverCheap(byte[] value,
                                               Coder.Context context)

Returns whether Coder.registerByteSizeObserver(T, org.apache.beam.sdk.util.common.ElementByteSizeObserver, org.apache.beam.sdk.coders.Coder.Context) 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.

Specified by:

isRegisterByteSizeObserverCheap in interface Coder<byte[]>

Overrides:

isRegisterByteSizeObserverCheap in class StandardCoder<byte[]>

Returns:

true since getEncodedElementByteSize(byte[], org.apache.beam.sdk.coders.Coder.Context) runs in constant time using the length of the provided array.

getEncodedElementByteSize

protected long getEncodedElementByteSize(byte[] value,
                                         Coder.Context context)
                                  throws Exception

Description copied from class: StandardCoder

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

Overrides:

getEncodedElementByteSize in class StandardCoder<byte[]>

Throws:

Exception