org.apache.flink.api.java

Class Utils

java.lang.Object

org.apache.flink.api.java.Utils

@Internal
public final class Utils
extends Object

Utility class that contains helper methods to work with Java APIs.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	Utils.ChecksumHashCode Accumulator of Utils.ChecksumHashCode.
static class	Utils.ChecksumHashCodeHelper<T> RichOutputFormat for Utils.ChecksumHashCode.
static class	Utils.CollectHelper<T> Utility sink function that collects elements into an accumulator, from which it they can be retrieved by the client.
static class	Utils.CountHelper<T> Utility sink function that counts elements and writes the count into an accumulator, from which it can be retrieved by the client.

Field Summary

Fields

Modifier and Type	Field and Description
static Random	RNG

Method Summary

Modifier and Type	Method and Description
static String	getCallLocationName()
static String	getCallLocationName(int depth)
static String	getKeyFromArgs(String[] args, int index) Get the key from the given args.
static <T> String	getSerializerTree(org.apache.flink.api.common.typeinfo.TypeInformation<T> ti) Debugging utility to understand the hierarchy of serializers created by the Java API.
static <T> Optional<T>	resolveFactory(ThreadLocal<T> threadLocalFactory, T staticFactory) Resolves the given factories.

Methods inherited from class java.lang.Object

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

Field Detail

RNG

public static final Random RNG

Method Detail

getCallLocationName

public static String getCallLocationName()

getCallLocationName

public static String getCallLocationName(int depth)

getSerializerTree

public static <T> String getSerializerTree(org.apache.flink.api.common.typeinfo.TypeInformation<T> ti)

Debugging utility to understand the hierarchy of serializers created by the Java API. Tested in GroupReduceITCase.testGroupByGenericType()

resolveFactory

public static <T> Optional<T> resolveFactory(ThreadLocal<T> threadLocalFactory,
                                             @Nullable
                                             T staticFactory)

Resolves the given factories. The thread local factory has preference over the static factory. If none is set, the method returns Optional.empty().

Type Parameters:

T - type of factory

Parameters:

threadLocalFactory - containing the thread local factory

staticFactory - containing the global factory

Returns:

Optional containing the resolved factory if it exists, otherwise it's empty

getKeyFromArgs

public static String getKeyFromArgs(String[] args,
                                    int index)

Get the key from the given args. Keys have to start with '-' or '--'. For example, --key1 value1 -key2 value2.

Parameters:

args - all given args.

index - the index of args to be parsed.

Returns:

the key of the given arg.