org.apache.beam.runners.spark.coders

Class CoderHelpers

java.lang.Object

org.apache.beam.runners.spark.coders.CoderHelpers

public final class CoderHelpers
extends java.lang.Object

Serialization utility class.

Method Summary

Modifier and Type	Method and Description
static <T> T	fromByteArray(byte[] serialized, Coder<T> coder) Utility method for deserializing a byte array using the specified coder.
static <T> java.lang.Iterable<T>	fromByteArrays(java.util.Collection<byte[]> serialized, Coder<T> coder) Utility method for deserializing a Iterable of byte arrays using the specified coder.
static <K,V> org.apache.spark.api.java.function.PairFunction<scala.Tuple2<ByteArray,byte[]>,K,V>	fromByteFunction(Coder<K> keyCoder, Coder<V> valueCoder) A function wrapper for converting a byte array pair to a key-value pair.
static <T> org.apache.spark.api.java.function.Function<byte[],T>	fromByteFunction(Coder<T> coder) A function wrapper for converting a byte array to an object.
static <K,V> org.apache.spark.api.java.function.PairFunction<scala.Tuple2<ByteArray,java.lang.Iterable<byte[]>>,K,java.lang.Iterable<V>>	fromByteFunctionIterable(Coder<K> keyCoder, Coder<V> valueCoder) A function wrapper for converting a byte array pair to a key-value pair, where values are Iterable.
static <T> byte[]	toByteArray(T value, Coder<T> coder) Utility method for serializing an object using the specified coder.
static <T> java.util.List<byte[]>	toByteArrays(java.lang.Iterable<T> values, Coder<T> coder) Utility method for serializing a Iterable of values using the specified coder.
static <K,V> org.apache.spark.api.java.function.PairFunction<scala.Tuple2<K,V>,ByteArray,byte[]>	toByteFunction(Coder<K> keyCoder, Coder<V> valueCoder) A function wrapper for converting a key-value pair to a byte array pair.
static <T> org.apache.spark.api.java.function.Function<T,byte[]>	toByteFunction(Coder<T> coder) A function wrapper for converting an object to a bytearray.

Methods inherited from class java.lang.Object

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

Method Detail

toByteArray

public static <T> byte[] toByteArray(T value,
                                     Coder<T> coder)

Utility method for serializing an object using the specified coder.

Type Parameters:

T - type of value that is serialized

Parameters:

value - Value to serialize.

coder - Coder to serialize with.

Returns:

Byte array representing serialized object.

toByteArrays

public static <T> java.util.List<byte[]> toByteArrays(java.lang.Iterable<T> values,
                                                      Coder<T> coder)

Utility method for serializing a Iterable of values using the specified coder.

Type Parameters:

T - type of value that is serialized

Parameters:

values - Values to serialize.

coder - Coder to serialize with.

Returns:

List of bytes representing serialized objects.

fromByteArray

public static <T> T fromByteArray(byte[] serialized,
                                  Coder<T> coder)

Utility method for deserializing a byte array using the specified coder.

Type Parameters:

T - Type of object to be returned.

Parameters:

serialized - bytearray to be deserialized.

coder - Coder to deserialize with.

Returns:

Deserialized object.

fromByteArrays

public static <T> java.lang.Iterable<T> fromByteArrays(java.util.Collection<byte[]> serialized,
                                                       Coder<T> coder)

Utility method for deserializing a Iterable of byte arrays using the specified coder.

Type Parameters:

T - Type of object to be returned.

Parameters:

serialized - bytearrays to be deserialized.

coder - Coder to deserialize with.

Returns:

Iterable of deserialized objects.

toByteFunction

public static <T> org.apache.spark.api.java.function.Function<T,byte[]> toByteFunction(Coder<T> coder)

A function wrapper for converting an object to a bytearray.

Type Parameters:

T - The type of the object being serialized.

Parameters:

coder - Coder to serialize with.

Returns:

A function that accepts an object and returns its coder-serialized form.

fromByteFunction

public static <T> org.apache.spark.api.java.function.Function<byte[],T> fromByteFunction(Coder<T> coder)

A function wrapper for converting a byte array to an object.

Type Parameters:

T - The type of the object being deserialized.

Parameters:

coder - Coder to deserialize with.

Returns:

A function that accepts a byte array and returns its corresponding object.

toByteFunction

public static <K,V> org.apache.spark.api.java.function.PairFunction<scala.Tuple2<K,V>,ByteArray,byte[]> toByteFunction(Coder<K> keyCoder,
                                                                                                                       Coder<V> valueCoder)

A function wrapper for converting a key-value pair to a byte array pair.

Type Parameters:

K - The type of the key being serialized.

V - The type of the value being serialized.

Parameters:

keyCoder - Coder to serialize keys.

valueCoder - Coder to serialize values.

Returns:

A function that accepts a key-value pair and returns a pair of byte arrays.

fromByteFunction

public static <K,V> org.apache.spark.api.java.function.PairFunction<scala.Tuple2<ByteArray,byte[]>,K,V> fromByteFunction(Coder<K> keyCoder,
                                                                                                                         Coder<V> valueCoder)

A function wrapper for converting a byte array pair to a key-value pair.

Type Parameters:

K - The type of the key being deserialized.

V - The type of the value being deserialized.

Parameters:

keyCoder - Coder to deserialize keys.

valueCoder - Coder to deserialize values.

Returns:

A function that accepts a pair of byte arrays and returns a key-value pair.

fromByteFunctionIterable

public static <K,V> org.apache.spark.api.java.function.PairFunction<scala.Tuple2<ByteArray,java.lang.Iterable<byte[]>>,K,java.lang.Iterable<V>> fromByteFunctionIterable(Coder<K> keyCoder,
                                                                                                                                                                         Coder<V> valueCoder)

A function wrapper for converting a byte array pair to a key-value pair, where values are Iterable.

Type Parameters:

K - The type of the key being deserialized.

V - The type of the value being deserialized.

Parameters:

keyCoder - Coder to deserialize keys.

valueCoder - Coder to deserialize values.

Returns:

A function that accepts a pair of byte arrays and returns a key-value pair.