Apache Avro 1.11.3 · org.apache.avro.message.BinaryMessageDecoder

A MessageDecoder that reads a binary-encoded datum. This checks for the datum header and decodes the payload with the schema that corresponds to the 8-byte schema fingerprint.

Instances can decode message payloads for known schemas, which are schemas added using addSchema(Schema), schemas resolved by the SchemaStore passed to the constructor, or the expected schema passed to the constructor. Messages encoded using an unknown schema will cause instances to throw a MissingSchemaException.

It is safe to continue using instances of this class after decode throws BadHeaderException or MissingSchemaException.

This class is thread-safe.

Modifier and Type	Field and Description
private final Map<Long, RawMessageDecoder<D>>	codecByFingerprint
private static final ThreadLocal<ByteBuffer>	FP_BUFFER
private static final ThreadLocal<byte[]>	HEADER_BUFFER
private final GenericData	model
private final Schema	readSchema
private final SchemaStore	resolver

Constructor Summary

Access	Constructor and Description
public	BinaryMessageDecoder(GenericData the `data model` for datum instances model, Schema the `Schema` used to construct datum instances readSchema) Creates a new `BinaryMessageEncoder` that uses the given `data model` to construct datum instances described by the `schema`.
public	BinaryMessageDecoder(GenericData the `data model` for datum instances model, Schema the `Schema` used to construct datum instances readSchema, SchemaStore a `SchemaStore` used to find schemas by fingerprint resolver) Creates a new `BinaryMessageEncoder` that uses the given `data model` to construct datum instances described by the `schema`.

Method Summary

Modifier and Type	Method and Description
public void	addSchema(Schema a `Schema` to use when decoding buffers writeSchema) Adds a `Schema` that can be used to decode buffers.
public D	decode(InputStream stream to read from stream, D a datum instance to reuse, avoiding instantiation if possible reuse) Implements org.apache.avro.message.MessageDecoder.decode. Deserialize a single datum from an InputStream.
private RawMessageDecoder<D>	getDecoder(long fp)
private boolean	Returns: true if the buffer is complete, false otherwise (stream ended) readFully(InputStream an InputStream to read from stream, byte[] a buffer bytes) Reads a buffer from a stream, making multiple read calls if necessary.

Inherited from org.apache.avro.message.MessageDecoder.BaseDecoder:: decode decode decode decode decode

Field Detail

codecByFingerprint	back to summary
private final Map<Long, RawMessageDecoder<D>> codecByFingerprint

FP_BUFFER	back to summary
private static final ThreadLocal<ByteBuffer> FP_BUFFER

HEADER_BUFFER	back to summary
private static final ThreadLocal<byte[]> HEADER_BUFFER

model	back to summary
private final GenericData model

readSchema	back to summary
private final Schema readSchema

resolver	back to summary
private final SchemaStore resolver

Constructor Detail

BinaryMessageDecoder back to summary

BinaryMessageDecoder	back to summary
public BinaryMessageDecoder(GenericData model, Schema readSchema) Creates a new `BinaryMessageEncoder` that uses the given `data model` to construct datum instances described by the `schema`. The `readSchema` is as used the expected schema (read schema). Datum instances created by this class will be described by the expected schema. If `readSchema` is `null`, the write schema of an incoming buffer is used as read schema for that datum instance. The schema used to decode incoming buffers is determined by the schema fingerprint encoded in the message header. This class can decode messages that were encoded using the `readSchema` (if any) and other schemas that are added using `addSchema(Schema)`. Parameters model:GenericData the `data model` for datum instances readSchema:Schema the `Schema` used to construct datum instances

public BinaryMessageDecoder(GenericData model, Schema readSchema)

Creates a new BinaryMessageEncoder that uses the given data model to construct datum instances described by the schema.

The readSchema is as used the expected schema (read schema). Datum instances created by this class will be described by the expected schema.

If readSchema is null, the write schema of an incoming buffer is used as read schema for that datum instance.

The schema used to decode incoming buffers is determined by the schema fingerprint encoded in the message header. This class can decode messages that were encoded using the readSchema (if any) and other schemas that are added using addSchema(Schema).

Parameters

model:GenericData: the data model for datum instances
readSchema:Schema: the Schema used to construct datum instances

BinaryMessageDecoder back to summary

BinaryMessageDecoder	back to summary
public BinaryMessageDecoder(GenericData model, Schema readSchema, SchemaStore resolver) Creates a new `BinaryMessageEncoder` that uses the given `data model` to construct datum instances described by the `schema`. The `readSchema` is used as the expected schema (read schema). Datum instances created by this class will be described by the expected schema. If `readSchema` is `null`, the write schema of an incoming buffer is used as read schema for that datum instance. The schema used to decode incoming buffers is determined by the schema fingerprint encoded in the message header. This class can decode messages that were encoded using the `readSchema` (if any), other schemas that are added using `addSchema(Schema)`, or schemas returned by the `resolver`. Parameters model:GenericData the `data model` for datum instances readSchema:Schema the `Schema` used to construct datum instances resolver:SchemaStore a `SchemaStore` used to find schemas by fingerprint

public BinaryMessageDecoder(GenericData model, Schema readSchema, SchemaStore resolver)

Creates a new BinaryMessageEncoder that uses the given data model to construct datum instances described by the schema.

The readSchema is used as the expected schema (read schema). Datum instances created by this class will be described by the expected schema.

If readSchema is null, the write schema of an incoming buffer is used as read schema for that datum instance.

The schema used to decode incoming buffers is determined by the schema fingerprint encoded in the message header. This class can decode messages that were encoded using the readSchema (if any), other schemas that are added using addSchema(Schema), or schemas returned by the resolver.

Parameters

model:GenericData: the data model for datum instances
readSchema:Schema: the Schema used to construct datum instances
resolver:SchemaStore: a SchemaStore used to find schemas by fingerprint

Method Detail

addSchema back to summary

addSchema	back to summary
public void addSchema(Schema writeSchema) Adds a `Schema` that can be used to decode buffers. Parameters writeSchema:Schema a `Schema` to use when decoding buffers

public void addSchema(Schema writeSchema)

Adds a Schema that can be used to decode buffers.

Parameters

writeSchema:Schema: a Schema to use when decoding buffers

decode	back to summary
public D decode(InputStream stream, D reuse) throws IOException Implements org.apache.avro.message.MessageDecoder.decode. Doc from org.apache.avro.message.MessageDecoder.decode. Deserialize a single datum from an InputStream. Parameters stream:InputStream stream to read from reuse:D a datum instance to reuse, avoiding instantiation if possible Returns:D a datum read from the stream Annotations @Override

decode

back to summary

public D decode(InputStream stream, D reuse) throws IOException

Implements org.apache.avro.message.MessageDecoder.decode.

Doc from org.apache.avro.message.MessageDecoder.decode.

Deserialize a single datum from an InputStream.

Parameters

stream:InputStream: stream to read from
reuse:D: a datum instance to reuse, avoiding instantiation if possible

Returns:D

a datum read from the stream

Annotations

@Override

getDecoder	back to summary
private RawMessageDecoder<D> getDecoder(long fp)

readFully	back to summary
private boolean readFully(InputStream stream, byte[] bytes) throws IOException Reads a buffer from a stream, making multiple read calls if necessary. Parameters stream:InputStream an InputStream to read from bytes:byte[] a buffer Returns:boolean true if the buffer is complete, false otherwise (stream ended)

readFully

back to summary

private boolean readFully(InputStream stream, byte[] bytes) throws IOException

Reads a buffer from a stream, making multiple read calls if necessary.

Parameters

stream:InputStream: an InputStream to read from
bytes:byte[]: a buffer

Returns:boolean

true if the buffer is complete, false otherwise (stream ended)

public Class BinaryMessageDecoder<D>

Field Summary

Constructor Summary

Method Summary

Field Detail

Constructor Detail

Method Detail