org.apache.beam.sdk.schemas.transforms

Class Convert

java.lang.Object

org.apache.beam.sdk.schemas.transforms.Convert

@Experimental(value=SCHEMAS)
public class Convert
extends java.lang.Object

A set of utilities for converting between different objects supporting schemas.

Constructor Summary

Constructors

Constructor and Description
Convert()

Method Summary

Modifier and Type	Method and Description
static <OutputT> PTransform<PCollection<Row>,PCollection<OutputT>>	fromRows(java.lang.Class<OutputT> clazz) Convert a PCollection<Row> into a PCollection<OutputT>.
static <OutputT> PTransform<PCollection<Row>,PCollection<OutputT>>	fromRows(TypeDescriptor<OutputT> typeDescriptor) Convert a PCollection<Row> into a PCollection<Row>.
static <InputT,OutputT> PTransform<PCollection<InputT>,PCollection<OutputT>>	to(java.lang.Class<OutputT> clazz) Convert a PCollection<InputT> to a PCollection<OutputT>.
static <InputT,OutputT> PTransform<PCollection<InputT>,PCollection<OutputT>>	to(TypeDescriptor<OutputT> typeDescriptor) Convert a PCollection<InputT> to a PCollection<OutputT>.
static <InputT> PTransform<PCollection<InputT>,PCollection<Row>>	toRows() Convert a PCollection<InputT> into a PCollection<Row>.

Methods inherited from class java.lang.Object

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

Constructor Detail

Convert

public Convert()

Method Detail

toRows

public static <InputT> PTransform<PCollection<InputT>,PCollection<Row>> toRows()

Convert a PCollection<InputT> into a PCollection<Row>.

The input PCollection must have a schema attached. The output collection will have the same schema as the input.

fromRows

public static <OutputT> PTransform<PCollection<Row>,PCollection<OutputT>> fromRows(java.lang.Class<OutputT> clazz)

Convert a PCollection<Row> into a PCollection<OutputT>.

The output schema will be inferred using the schema registry. A schema must be registered for this type, or the conversion will fail.

fromRows

public static <OutputT> PTransform<PCollection<Row>,PCollection<OutputT>> fromRows(TypeDescriptor<OutputT> typeDescriptor)

Convert a PCollection<Row> into a PCollection<Row>.

The output schema will be inferred using the schema registry. A schema must be registered for this type, or the conversion will fail.

to

public static <InputT,OutputT> PTransform<PCollection<InputT>,PCollection<OutputT>> to(java.lang.Class<OutputT> clazz)

Convert a PCollection<InputT> to a PCollection<OutputT>.

This function allows converting between two types as long as the two types have compatible schemas. Two schemas are said to be compatible if they recursively have fields with the same names, but possibly different orders. If the source schema can be unboxed to match the target schema (i.e. the source schema contains a single field that is compatible with the target schema), then conversion also succeeds.

to

public static <InputT,OutputT> PTransform<PCollection<InputT>,PCollection<OutputT>> to(TypeDescriptor<OutputT> typeDescriptor)

Convert a PCollection<InputT> to a PCollection<OutputT>.

This function allows converting between two types as long as the two types have compatible schemas. Two schemas are said to be compatible if they recursively have fields with the same names, but possibly different orders. If the source schema can be unboxed to match the target schema (i.e. the source schema contains a single field that is compatible with the target schema), then conversion also succeeds.