at.chrl.nutils

Class StreamUtils

java.lang.Object

at.chrl.nutils.StreamUtils

public final class StreamUtils
extends Object

Author:

Christian Richard Leopold - ChRL
Mar 13, 2015 - 9:01:13 PM

Method Summary

Modifier and Type	Method and Description
static <T,R> Function<T,R>	catchException(Function<T,R> func)
static <T,R extends Comparable<R>> Comparator<T>	getComparator(boolean reverse, Function<T,R>... getters) returns comparator by getter functions
static <T,R extends Comparable<R>> Comparator<T>	getComparator(Function<T,R>... getters) returns comparator by getter functions
static <T,R extends Comparable<R>> Comparator<T>	getComparator(Function<T,R> getter, boolean reverse) returns comparator for gicen getter function
static <E extends Map.Entry<K,V>,K extends Comparable<K>,V> Comparator<E>	getKeyComparator() Returns Comparator for quick map entry sorting Compares by key
static <E extends Map.Entry<K,V>,K extends Comparable<K>,V> Comparator<E>	getKeyComparator(boolean reverse) Returns Comparator for quick map entry sorting Compares by key
static <E extends Map.Entry<K,V>,K,V extends Comparable<V>> Comparator<E>	getValueComparator() Returns Comparator for quick map entry sorting Compares by value
static <E extends Map.Entry<K,V>,K,V extends Comparable<V>> Comparator<E>	getValueComparator(boolean reverse) Returns Comparator for quick map entry sorting Compares by value
static <T> Function<T,T>	identity() identity function
static boolean	isBlankOrNull(Collection<?> c)
static boolean	isBlankOrNull(Map<?,?> m)
static boolean	isBlankOrNull(Number n)
static boolean	isBlankOrNull(Object[] a)
static boolean	isBlankOrNull(String s)
static <T> BinaryOperator<T>	keepFirst() binary keep first function
static <T> BinaryOperator<T>	keepLast() binary keep last function
static <R,T> Function<R,T>	parse(Function<R,T> parseFunction, T defaultValue)
static Function<? extends Number,Boolean>	parseNumberToBoolean()
static Function<String,Boolean>	parseStringToBoolean()
static <T> Function<String,T>	parseStringToNumeric(BiFunction<String,Integer,T> parseFunction, int radix, T defaultValue)
static Function<String,Byte>	parseToByte()
static Function<String,Byte>	parseToByte(int radix)
static Function<String,Double>	parseToDouble()
static Function<String,Float>	parseToFloat()
static Function<String,Integer>	parseToInt()
static Function<String,Integer>	parseToInt(int radix)
static Function<String,Long>	parseToLong()
static Function<String,Long>	parseToLong(int radix)
static Function<String,Short>	parseToShort()
static Function<String,Short>	parseToShort(int radix)
static Function<String,Long>	parseToULong()
static Function<String,Long>	parseToULong(int radix)
static <T> Function<T,T>	printOut() identity function and print on System.out
static <T> Function<T,T>	printOut(PrintStream out) identity function with print on given stream
static <T> Stream<T>	rangeStream(T start, T end, UnaryOperator<T> incrementFunction) creates a range stream of given type T.
static <T,K> Collector<T,?,Map<K,T>>	toMap(Function<T,K> keyMapper) Collectors.toMap(Function, Function, BinaryOperator, java.util.function.Supplier) override returns toMap function with given key Mapper.
static <T,K> Collector<T,?,Map<K,T>>	toMapKeepLast(Function<T,K> keyMapper) Collectors.toMap(Function, Function, BinaryOperator, java.util.function.Supplier) override returns toMap function with given key Mapper.
static <T,K> Collector<T,?,Map<K,Collection<T>>>	toMultimap(Function<T,K> keyMapper) Collector to collect values into multimaps
static <T> Function<T,T>	toNull() to null function
static <T> Function<T,T>	waitFunction(long millis)

Methods inherited from class java.lang.Object

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

Method Detail

identity

public static <T> Function<T,T> identity()

identity function

Returns:

identity function

See Also:

UnaryOperator#identity()}

printOut

public static <T> Function<T,T> printOut()

identity function and print on System.out

Returns:

identity function with print

printOut

public static <T> Function<T,T> printOut(PrintStream out)

identity function with print on given stream

Parameters:

out - - given outputStream

Returns:

toNull

public static <T> Function<T,T> toNull()

to null function

Returns:

to null function

keepFirst

public static <T> BinaryOperator<T> keepFirst()

binary keep first function

Returns:

keep first function

keepLast

public static <T> BinaryOperator<T> keepLast()

binary keep last function

Returns:

keep last function

toMap

public static <T,K> Collector<T,?,Map<K,T>> toMap(Function<T,K> keyMapper)

Collectors.toMap(Function, Function, BinaryOperator, java.util.function.Supplier) override returns toMap function with given key Mapper. Keeps first if duplicates

Parameters:

keyMapper -

Returns:

mapper function

toMapKeepLast

public static <T,K> Collector<T,?,Map<K,T>> toMapKeepLast(Function<T,K> keyMapper)

Collectors.toMap(Function, Function, BinaryOperator, java.util.function.Supplier) override returns toMap function with given key Mapper. Keeps last if duplicates

Parameters:

keyMapper -

Returns:

mapper function

toMultimap

public static <T,K> Collector<T,?,Map<K,Collection<T>>> toMultimap(Function<T,K> keyMapper)

Collector to collect values into multimaps

Parameters:

keyMapper -

Returns:

collector

rangeStream

public static final <T> Stream<T> rangeStream(T start,
                                              T end,
                                              UnaryOperator<T> incrementFunction)

creates a range stream of given type T.

checks if value after applying the increment function equals the end value.

BEWARE: INFITE LOOP IF END VALUE IS NEVER REACHED BY INCREMENT FUNCTION

Parameters:

start - - start value of stream

end - - end value of stream

incrementFunction - - increment function

Returns:

stream

getComparator

public static final <T,R extends Comparable<R>> Comparator<T> getComparator(Function<T,R> getter,
                                                                            boolean reverse)

returns comparator for gicen getter function

Parameters:

getter -

reverse - for reverse rodering

Returns:

getComparator

@SafeVarargs
public static final <T,R extends Comparable<R>> Comparator<T> getComparator(Function<T,R>... getters)

returns comparator by getter functions

Parameters:

getters -

Returns:

comparator

getComparator

@SafeVarargs
public static final <T,R extends Comparable<R>> Comparator<T> getComparator(boolean reverse,
                                                                                          Function<T,R>... getters)

returns comparator by getter functions

Parameters:

reverse - - for reverse ordering

getters -

Returns:

comparator

getKeyComparator

public static final <E extends Map.Entry<K,V>,K extends Comparable<K>,V> Comparator<E> getKeyComparator(boolean reverse)

Returns Comparator for quick map entry sorting Compares by key

Parameters:

reverse - - for reverse sorting

Returns:

key comparator

getKeyComparator

public static final <E extends Map.Entry<K,V>,K extends Comparable<K>,V> Comparator<E> getKeyComparator()

Returns Comparator for quick map entry sorting Compares by key

Returns:

key comparator

getValueComparator

public static final <E extends Map.Entry<K,V>,K,V extends Comparable<V>> Comparator<E> getValueComparator(boolean reverse)

Returns Comparator for quick map entry sorting Compares by value

Parameters:

reverse - - for reverse sorting

Returns:

value comparator

getValueComparator

public static final <E extends Map.Entry<K,V>,K,V extends Comparable<V>> Comparator<E> getValueComparator()

Returns Comparator for quick map entry sorting Compares by value

Returns:

value comparator

parse

public static final <R,T> Function<R,T> parse(Function<R,T> parseFunction,
                                              T defaultValue)

parseStringToNumeric

public static final <T> Function<String,T> parseStringToNumeric(BiFunction<String,Integer,T> parseFunction,
                                                                int radix,
                                                                T defaultValue)

parseToLong

public static final Function<String,Long> parseToLong()

parseToLong

public static final Function<String,Long> parseToLong(int radix)

parseToShort

public static final Function<String,Short> parseToShort()

parseToShort

public static final Function<String,Short> parseToShort(int radix)

parseToInt

public static final Function<String,Integer> parseToInt()

parseToInt

public static final Function<String,Integer> parseToInt(int radix)

parseToULong

public static final Function<String,Long> parseToULong()

parseToULong

public static final Function<String,Long> parseToULong(int radix)

parseToByte

public static final Function<String,Byte> parseToByte()

parseToByte

public static final Function<String,Byte> parseToByte(int radix)

parseToDouble

public static final Function<String,Double> parseToDouble()

parseToFloat

public static final Function<String,Float> parseToFloat()

parseStringToBoolean

public static final Function<String,Boolean> parseStringToBoolean()

parseNumberToBoolean

public static final Function<? extends Number,Boolean> parseNumberToBoolean()

waitFunction

public static final <T> Function<T,T> waitFunction(long millis)

catchException

public static <T,R> Function<T,R> catchException(Function<T,R> func)

isBlankOrNull

public static boolean isBlankOrNull(String s)

isBlankOrNull

public static boolean isBlankOrNull(Collection<?> c)

isBlankOrNull

public static boolean isBlankOrNull(Map<?,?> m)

isBlankOrNull

public static boolean isBlankOrNull(Number n)

isBlankOrNull

public static boolean isBlankOrNull(Object[] a)