Package org.apache.flink.formats.json

Class JsonRowDeserializationSchema

java.lang.Object

org.apache.flink.formats.json.JsonRowDeserializationSchema

All Implemented Interfaces:

Serializable, DeserializationSchema<Row>, ResultTypeQueryable<Row>

@Internal
public class JsonRowDeserializationSchema
extends Object
implements DeserializationSchema<Row>

Deserialization schema from JSON to Flink types.

Deserializes a byte[] message as a JSON object and reads the specified fields.

Failures during deserialization are forwarded as wrapped IOExceptions.

See Also:

Serialized Form

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	JsonRowDeserializationSchema.Builder	Builder for JsonRowDeserializationSchema.

Nested classes/interfaces inherited from interface org.apache.flink.api.common.serialization.DeserializationSchema

DeserializationSchema.InitializationContext

Constructor Summary

Constructors

Constructor	Description
JsonRowDeserializationSchema(String jsonSchema)
JsonRowDeserializationSchema(TypeInformation<Row> typeInfo)

Method Summary

Modifier and Type	Method	Description
Row	deserialize(byte[] message)	Deserializes the byte message.
boolean	equals(Object o)
TypeInformation<Row>	getProducedType()	Gets the data type (as a TypeInformation) produced by this function or input format.
int	hashCode()
boolean	isEndOfStream(Row nextElement)	Method to decide whether the element signals the end of the stream.
void	open(DeserializationSchema.InitializationContext context)	Initialization method for the schema.

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.flink.api.common.serialization.DeserializationSchema

deserialize

Constructor Detail

JsonRowDeserializationSchema

public JsonRowDeserializationSchema(TypeInformation<Row> typeInfo)

JsonRowDeserializationSchema

public JsonRowDeserializationSchema(String jsonSchema)

Method Detail

open

public void open(DeserializationSchema.InitializationContext context)
          throws Exception

Description copied from interface: DeserializationSchema

Initialization method for the schema. It is called before the actual working methods DeserializationSchema.deserialize(byte[]) and thus suitable for one time setup work.

The provided DeserializationSchema.InitializationContext can be used to access additional features such as e.g. registering user metrics.

Specified by:

open in interface DeserializationSchema<Row>

Parameters:

context - Contextual information that can be used during initialization.

Throws:

Exception

deserialize

public Row deserialize(byte[] message)
                throws IOException

Description copied from interface: DeserializationSchema

Deserializes the byte message.

Specified by:

deserialize in interface DeserializationSchema<Row>

Parameters:

message - The message, as a byte array.

Returns:

The deserialized message as an object (null if the message cannot be deserialized).

Throws:

IOException

isEndOfStream

public boolean isEndOfStream(Row nextElement)

Description copied from interface: DeserializationSchema

Method to decide whether the element signals the end of the stream. If true is returned the element won't be emitted.

Specified by:

isEndOfStream in interface DeserializationSchema<Row>

Parameters:

nextElement - The element to test for the end-of-stream signal.

Returns:

True, if the element signals end of stream, false otherwise.

getProducedType

public TypeInformation<Row> getProducedType()

Description copied from interface: ResultTypeQueryable

Gets the data type (as a TypeInformation) produced by this function or input format.

Specified by:

getProducedType in interface ResultTypeQueryable<Row>

Returns:

The data type produced by this function or input format.

equals

public boolean equals(Object o)

Overrides:

equals in class Object

hashCode

public int hashCode()

Overrides:

hashCode in class Object