org.apache.beam.sdk.schemas

Interface SchemaProvider

All Superinterfaces:

java.io.Serializable

All Known Implementing Classes:

AutoValueSchema, AvroRecordSchema, DefaultSchema.DefaultSchemaProvider, GetterBasedSchemaProvider, JavaBeanSchema, JavaFieldSchema, ProtoMessageSchema, ThriftSchema

@Experimental(value=SCHEMAS)
public interface SchemaProvider
extends java.io.Serializable

Concrete implementations of this class allow creation of schema service objects that vend a Schema for a specific type. One example use: creating a SchemaProvider that contacts an external schema-registry service to determine the schema for a type.

Method Summary

Modifier and Type	Method and Description
<T> @Nullable SerializableFunction<Row,T>	fromRowFunction(TypeDescriptor<T> typeDescriptor) Given a type, returns a function that converts from a Row object to that type.
<T> @Nullable Schema	schemaFor(TypeDescriptor<T> typeDescriptor) Lookup a schema for the given type.
<T> @Nullable SerializableFunction<T,Row>	toRowFunction(TypeDescriptor<T> typeDescriptor) Given a type, return a function that converts that type to a Row object If no schema exists, returns null.

Method Detail

schemaFor

<T> @Nullable Schema schemaFor(TypeDescriptor<T> typeDescriptor)

Lookup a schema for the given type. If no schema exists, returns null.

toRowFunction

<T> @Nullable SerializableFunction<T,Row> toRowFunction(TypeDescriptor<T> typeDescriptor)

Given a type, return a function that converts that type to a Row object If no schema exists, returns null.

fromRowFunction

<T> @Nullable SerializableFunction<Row,T> fromRowFunction(TypeDescriptor<T> typeDescriptor)

Given a type, returns a function that converts from a Row object to that type. If no schema exists, returns null.