public class Min
extends java.lang.Object
PTransforms for computing the minimum of the elements in a PCollection, or the
minimum of the values associated with each key in a PCollection of KVs.
Example 1: get the minimum of a PCollection of Doubles.
PCollection<Double> input = ...;
PCollection<Double> min = input.apply(Min.doublesGlobally());
Example 2: calculate the minimum of the Integers associated with each unique key
(which is of type String).
PCollection<KV<String, Integer>> input = ...;
PCollection<KV<String, Integer>> minPerKey = input
.apply(Min.<String>integersPerKey());
| Modifier and Type | Method and Description |
|---|---|
static Combine.Globally<java.lang.Double,java.lang.Double> |
doublesGlobally()
Returns a
PTransform that takes an input PCollection<Double> and returns a
PCollection<Double> whose contents is the minimum of the input PCollection's
elements, or Double.POSITIVE_INFINITY if there are no elements. |
static <K> Combine.PerKey<K,java.lang.Double,java.lang.Double> |
doublesPerKey()
Returns a
PTransform that takes an input PCollection<KV<K, Double>> and returns
a PCollection<KV<K, Double>> that contains an output element mapping each distinct key
in the input PCollection to the minimum of the values associated with that key in the
input PCollection. |
static <T extends java.lang.Comparable<? super T>> |
globally()
Returns a
PTransform that takes an input PCollection<T> and returns a PCollection<T> whose contents is the minimum according to the natural ordering of T of
the input PCollection's elements, or null if there are no elements. |
static <T,ComparatorT extends java.util.Comparator<? super T> & java.io.Serializable> |
globally(ComparatorT comparator)
Returns a
PTransform that takes an input PCollection<T> and returns a PCollection<T> whose contents is the minimum of the input PCollection's elements, or
null if there are no elements. |
static Combine.Globally<java.lang.Integer,java.lang.Integer> |
integersGlobally()
Returns a
PTransform that takes an input PCollection<Integer> and returns a
PCollection<Integer> whose contents is a single value that is the minimum of the input
PCollection's elements, or Integer.MAX_VALUE if there are no elements. |
static <K> Combine.PerKey<K,java.lang.Integer,java.lang.Integer> |
integersPerKey()
Returns a
PTransform that takes an input PCollection<KV<K, Integer>> and
returns a PCollection<KV<K, Integer>> that contains an output element mapping each
distinct key in the input PCollection to the minimum of the values associated with that
key in the input PCollection. |
static Combine.Globally<java.lang.Long,java.lang.Long> |
longsGlobally()
Returns a
PTransform that takes an input PCollection<Long> and returns a PCollection<Long> whose contents is the minimum of the input PCollection's elements,
or Long.MAX_VALUE if there are no elements. |
static <K> Combine.PerKey<K,java.lang.Long,java.lang.Long> |
longsPerKey()
Returns a
PTransform that takes an input PCollection<KV<K, Long>> and returns a
PCollection<KV<K, Long>> that contains an output element mapping each distinct key in
the input PCollection to the minimum of the values associated with that key in the
input PCollection. |
static <T extends java.lang.Comparable<? super T>> |
naturalOrder() |
static <T extends java.lang.Comparable<? super T>> |
naturalOrder(T identity) |
static <T,ComparatorT extends java.util.Comparator<? super T> & java.io.Serializable> |
of(ComparatorT comparator)
A
CombineFn that computes the minimum of a collection of elements of type T
using an arbitrary Comparator, useful as an argument to Combine.globally(org.apache.beam.sdk.transforms.SerializableFunction<java.lang.Iterable<V>, V>) or
Combine.perKey(org.apache.beam.sdk.transforms.SerializableFunction<java.lang.Iterable<V>, V>). |
static <T,ComparatorT extends java.util.Comparator<? super T> & java.io.Serializable> |
of(T identity,
ComparatorT comparator)
A
CombineFn that computes the minimum of a collection of elements of type T
using an arbitrary Comparator and an identity, useful as an argument to Combine.globally(org.apache.beam.sdk.transforms.SerializableFunction<java.lang.Iterable<V>, V>) or Combine.perKey(org.apache.beam.sdk.transforms.SerializableFunction<java.lang.Iterable<V>, V>). |
static Combine.BinaryCombineDoubleFn |
ofDoubles()
A
CombineFn that computes the minimum of a collection of Doubles, useful as an
argument to Combine.globally(org.apache.beam.sdk.transforms.SerializableFunction<java.lang.Iterable<V>, V>) or Combine.perKey(org.apache.beam.sdk.transforms.SerializableFunction<java.lang.Iterable<V>, V>). |
static Combine.BinaryCombineIntegerFn |
ofIntegers()
A
CombineFn that computes the minimum of a collection of Integers, useful as an
argument to Combine.globally(org.apache.beam.sdk.transforms.SerializableFunction<java.lang.Iterable<V>, V>) or Combine.perKey(org.apache.beam.sdk.transforms.SerializableFunction<java.lang.Iterable<V>, V>). |
static Combine.BinaryCombineLongFn |
ofLongs()
A
CombineFn that computes the minimum of a collection of Longs, useful as an
argument to Combine.globally(org.apache.beam.sdk.transforms.SerializableFunction<java.lang.Iterable<V>, V>) or Combine.perKey(org.apache.beam.sdk.transforms.SerializableFunction<java.lang.Iterable<V>, V>). |
static <K,T extends java.lang.Comparable<? super T>> |
perKey()
Returns a
PTransform that takes an input PCollection<KV<K, T>> and returns a
PCollection<KV<K, T>> that contains an output element mapping each distinct key in the
input PCollection to the minimum according to the natural ordering of T of the
values associated with that key in the input PCollection. |
static <K,T,ComparatorT extends java.util.Comparator<? super T> & java.io.Serializable> |
perKey(ComparatorT comparator)
Returns a
PTransform that takes an input PCollection<KV<K, T>> and returns a
PCollection<KV<K, T>> that contains one output element per key mapping each to the
minimum of the values associated with that key in the input PCollection. |
public static Combine.Globally<java.lang.Integer,java.lang.Integer> integersGlobally()
PTransform that takes an input PCollection<Integer> and returns a
PCollection<Integer> whose contents is a single value that is the minimum of the input
PCollection's elements, or Integer.MAX_VALUE if there are no elements.public static <K> Combine.PerKey<K,java.lang.Integer,java.lang.Integer> integersPerKey()
PTransform that takes an input PCollection<KV<K, Integer>> and
returns a PCollection<KV<K, Integer>> that contains an output element mapping each
distinct key in the input PCollection to the minimum of the values associated with that
key in the input PCollection.
See Combine.PerKey for how this affects timestamps and windowing.
public static Combine.Globally<java.lang.Long,java.lang.Long> longsGlobally()
PTransform that takes an input PCollection<Long> and returns a PCollection<Long> whose contents is the minimum of the input PCollection's elements,
or Long.MAX_VALUE if there are no elements.public static <K> Combine.PerKey<K,java.lang.Long,java.lang.Long> longsPerKey()
PTransform that takes an input PCollection<KV<K, Long>> and returns a
PCollection<KV<K, Long>> that contains an output element mapping each distinct key in
the input PCollection to the minimum of the values associated with that key in the
input PCollection.
See Combine.PerKey for how this affects timestamps and windowing.
public static Combine.Globally<java.lang.Double,java.lang.Double> doublesGlobally()
PTransform that takes an input PCollection<Double> and returns a
PCollection<Double> whose contents is the minimum of the input PCollection's
elements, or Double.POSITIVE_INFINITY if there are no elements.public static <K> Combine.PerKey<K,java.lang.Double,java.lang.Double> doublesPerKey()
PTransform that takes an input PCollection<KV<K, Double>> and returns
a PCollection<KV<K, Double>> that contains an output element mapping each distinct key
in the input PCollection to the minimum of the values associated with that key in the
input PCollection.
See Combine.PerKey for how this affects timestamps and windowing.
public static Combine.BinaryCombineIntegerFn ofIntegers()
CombineFn that computes the minimum of a collection of Integers, useful as an
argument to Combine.globally(org.apache.beam.sdk.transforms.SerializableFunction<java.lang.Iterable<V>, V>) or Combine.perKey(org.apache.beam.sdk.transforms.SerializableFunction<java.lang.Iterable<V>, V>).public static Combine.BinaryCombineLongFn ofLongs()
CombineFn that computes the minimum of a collection of Longs, useful as an
argument to Combine.globally(org.apache.beam.sdk.transforms.SerializableFunction<java.lang.Iterable<V>, V>) or Combine.perKey(org.apache.beam.sdk.transforms.SerializableFunction<java.lang.Iterable<V>, V>).public static Combine.BinaryCombineDoubleFn ofDoubles()
CombineFn that computes the minimum of a collection of Doubles, useful as an
argument to Combine.globally(org.apache.beam.sdk.transforms.SerializableFunction<java.lang.Iterable<V>, V>) or Combine.perKey(org.apache.beam.sdk.transforms.SerializableFunction<java.lang.Iterable<V>, V>).public static <T,ComparatorT extends java.util.Comparator<? super T> & java.io.Serializable> Combine.BinaryCombineFn<T> of(T identity, ComparatorT comparator)
CombineFn that computes the minimum of a collection of elements of type T
using an arbitrary Comparator and an identity, useful as an argument to Combine.globally(org.apache.beam.sdk.transforms.SerializableFunction<java.lang.Iterable<V>, V>) or Combine.perKey(org.apache.beam.sdk.transforms.SerializableFunction<java.lang.Iterable<V>, V>).T - the type of the values being comparedpublic static <T,ComparatorT extends java.util.Comparator<? super T> & java.io.Serializable> Combine.BinaryCombineFn<T> of(ComparatorT comparator)
CombineFn that computes the minimum of a collection of elements of type T
using an arbitrary Comparator, useful as an argument to Combine.globally(org.apache.beam.sdk.transforms.SerializableFunction<java.lang.Iterable<V>, V>) or
Combine.perKey(org.apache.beam.sdk.transforms.SerializableFunction<java.lang.Iterable<V>, V>).T - the type of the values being comparedpublic static <T extends java.lang.Comparable<? super T>> Combine.BinaryCombineFn<T> naturalOrder(T identity)
public static <T extends java.lang.Comparable<? super T>> Combine.BinaryCombineFn<T> naturalOrder()
public static <T extends java.lang.Comparable<? super T>> Combine.Globally<T,T> globally()
PTransform that takes an input PCollection<T> and returns a PCollection<T> whose contents is the minimum according to the natural ordering of T of
the input PCollection's elements, or null if there are no elements.public static <K,T extends java.lang.Comparable<? super T>> Combine.PerKey<K,T,T> perKey()
PTransform that takes an input PCollection<KV<K, T>> and returns a
PCollection<KV<K, T>> that contains an output element mapping each distinct key in the
input PCollection to the minimum according to the natural ordering of T of the
values associated with that key in the input PCollection.
See Combine.PerKey for how this affects timestamps and windowing.
public static <T,ComparatorT extends java.util.Comparator<? super T> & java.io.Serializable> Combine.Globally<T,T> globally(ComparatorT comparator)
PTransform that takes an input PCollection<T> and returns a PCollection<T> whose contents is the minimum of the input PCollection's elements, or
null if there are no elements.public static <K,T,ComparatorT extends java.util.Comparator<? super T> & java.io.Serializable> Combine.PerKey<K,T,T> perKey(ComparatorT comparator)
PTransform that takes an input PCollection<KV<K, T>> and returns a
PCollection<KV<K, T>> that contains one output element per key mapping each to the
minimum of the values associated with that key in the input PCollection.
See Combine.PerKey for how this affects timestamps and windowing.