public class Min
extends java.lang.Object
PTransform
s for computing the minimum of the elements in a PCollection
, or the
minimum of the values associated with each key in a PCollection
of KV
s.
Example 1: get the minimum of a PCollection
of Double
s.
PCollection<Double> input = ...;
PCollection<Double> min = input.apply(Min.doublesGlobally());
Example 2: calculate the minimum of the Integer
s
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 Double s, 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 Integer s, 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 Long s, 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 Integer
s, 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 Long
s, 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 Double
s, 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.