Create (Google Cloud Dataflow SDK 1.9.1 API)

Google Cloud Dataflow SDK for Java, version 1.9.1

java.lang.Object
- com.google.cloud.dataflow.sdk.transforms.Create<T>

Type Parameters:

T - the type of the elements of the resulting PCollection
```
public class Create<T>
extends Object
```
Create<T> takes a collection of elements of type T known when the pipeline is constructed and returns a PCollection<T> containing the elements.
Example of use:
```
 
 Pipeline p = ...;

 PCollection<Integer> pc = p.apply(Create.of(3, 4, 5).withCoder(BigEndianIntegerCoder.of()));

 Map<String, Integer> map = ...;
 PCollection<KV<String, Integer>> pt =
     p.apply(Create.of(map)
      .withCoder(KvCoder.of(StringUtf8Coder.of(),
                            BigEndianIntegerCoder.of())));
  
```
Create can automatically determine the Coder to use if all elements have the same run-time class, and a default coder is registered for that class. See CoderRegistry for details on how defaults are determined.
If a coder can not be inferred, Create.Values.withCoder(com.google.cloud.dataflow.sdk.coders.Coder<T>) must be called explicitly to set the encoding of the resulting PCollection.
A good use for Create is when a PCollection needs to be created without dependencies on files or other external entities. This is especially useful during testing.
Caveat: Create only supports small in-memory datasets, particularly when submitting jobs to the Google Cloud Dataflow service.

Nested Class Summary

Nested Classes
Modifier and Type	Class and Description
`static class`	`Create.TimestampedValues<T>` A `PTransform` that creates a `PCollection` whose elements have associated timestamps.
`static class`	`Create.Values<T>` A `PTransform` that creates a `PCollection` from a set of in-memory objects.

Constructor Summary

Constructors
Constructor and Description

Create()

Method Summary

All Methods Static Methods Concrete Methods
Modifier and Type	Method and Description
`static <T> Create.Values<T>`	`of(Iterable<T> elems)` Returns a new `Create.Values` transform that produces a `PCollection` containing elements of the provided `Iterable`.
`static <K,V> Create.Values<KV<K,V>>`	`of(Map<K,V> elems)` Returns a new `Create.Values` transform that produces a `PCollection` of `KV`s corresponding to the keys and values of the specified `Map`.
`static <T> Create.Values<T>`	`of(T... elems)` Returns a new `Create.Values` transform that produces a `PCollection` containing the specified elements.
`static <T> Create.TimestampedValues<T>`	`timestamped(Iterable<T> values, Iterable<Long> timestamps)` Returns a new root transform that produces a `PCollection` containing the specified elements with the specified timestamps.
`static <T> Create.TimestampedValues<T>`	`timestamped(Iterable<TimestampedValue<T>> elems)` Returns a new `Create.TimestampedValues` transform that produces a `PCollection` containing the elements of the provided `Iterable` with the specified timestamps.
`static <T> Create.TimestampedValues<T>`	`timestamped(TimestampedValue<T>... elems)` Returns a new `Create.TimestampedValues` transform that produces a `PCollection` containing the specified elements with the specified timestamps.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Constructor Detail
  - Create
```
public Create()
```
- Method Detail
  - of
```
public static <T> Create.Values<T> of(Iterable<T> elems)
```
    Returns a new Create.Values transform that produces a PCollection containing elements of the provided Iterable.
    The argument should not be modified after this is called.
    The elements of the output PCollection will have a timestamp of negative infinity, see timestamped(java.lang.Iterable<com.google.cloud.dataflow.sdk.values.TimestampedValue<T>>) for a way of creating a PCollection with timestamped elements.
    By default, Create.Values can automatically determine the Coder to use if all elements have the same non-parameterized run-time class, and a default coder is registered for that class. See CoderRegistry for details on how defaults are determined. Otherwise, use Create.Values.withCoder(com.google.cloud.dataflow.sdk.coders.Coder<T>) to set the coder explicitly.
  - of
```
@SafeVarargs
public static <T> Create.Values<T> of(T... elems)
```
    Returns a new Create.Values transform that produces a PCollection containing the specified elements.
    The elements will have a timestamp of negative infinity, see timestamped(java.lang.Iterable<com.google.cloud.dataflow.sdk.values.TimestampedValue<T>>) for a way of creating a PCollection with timestamped elements.
    The arguments should not be modified after this is called.
    By default, Create.Values can automatically determine the Coder to use if all elements have the same non-parameterized run-time class, and a default coder is registered for that class. See CoderRegistry for details on how defaults are determined. Otherwise, use Create.Values.withCoder(com.google.cloud.dataflow.sdk.coders.Coder<T>) to set the coder explicitly.
  - of
```
public static <K,V> Create.Values<KV<K,V>> of(Map<K,V> elems)
```
    Returns a new Create.Values transform that produces a PCollection of KVs corresponding to the keys and values of the specified Map.
    The elements will have a timestamp of negative infinity, see timestamped(java.lang.Iterable<com.google.cloud.dataflow.sdk.values.TimestampedValue<T>>) for a way of creating a PCollection with timestamped elements.
    By default, Create.Values can automatically determine the Coder to use if all elements have the same non-parameterized run-time class, and a default coder is registered for that class. See CoderRegistry for details on how defaults are determined. Otherwise, use Create.Values.withCoder(com.google.cloud.dataflow.sdk.coders.Coder<T>) to set the coder explicitly.
  - timestamped
```
public static <T> Create.TimestampedValues<T> timestamped(Iterable<TimestampedValue<T>> elems)
```
    Returns a new Create.TimestampedValues transform that produces a PCollection containing the elements of the provided Iterable with the specified timestamps.
    The argument should not be modified after this is called.
    By default, Create.TimestampedValues can automatically determine the Coder to use if all elements have the same non-parameterized run-time class, and a default coder is registered for that class. See CoderRegistry for details on how defaults are determined. Otherwise, use Create.TimestampedValues.withCoder(com.google.cloud.dataflow.sdk.coders.Coder<T>) to set the coder explicitly.
  - timestamped
```
@SafeVarargs
public static <T> Create.TimestampedValues<T> timestamped(TimestampedValue<T>... elems)
```
    Returns a new Create.TimestampedValues transform that produces a PCollection containing the specified elements with the specified timestamps.
    The arguments should not be modified after this is called.
  - timestamped
```
public static <T> Create.TimestampedValues<T> timestamped(Iterable<T> values,
                                                          Iterable<Long> timestamps)
```
    Returns a new root transform that produces a PCollection containing the specified elements with the specified timestamps.
    The arguments should not be modified after this is called.
    By default, Create.TimestampedValues can automatically determine the Coder to use if all elements have the same non-parameterized run-time class, and a default coder is registered for that class. See CoderRegistry for details on how defaults are determined. Otherwise, use Create.TimestampedValues.withCoder(com.google.cloud.dataflow.sdk.coders.Coder<T>) to set the coder explicitly.
    
    Throws:
    
    IllegalArgumentException - if there are a different number of values and timestamps

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Sist oppdatert desember 4, 2019.

Create (Google Cloud Dataflow SDK 1.9.1 API)

Google Cloud Dataflow SDK for Java, version 1.9.1

Class Create<T>

Nested Class Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

Create

Method Detail

of

of

of

timestamped

timestamped

timestamped

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