de.fhg.fokus.xtensions.stream

Class StringStreamExtensions

java.lang.Object

de.fhg.fokus.xtensions.stream.StringStreamExtensions

public final class StringStreamExtensions
extends Object

This class provides extension methods for Stream<String> and in some cases for Stream<? extends CharSequence>.

Method Summary

Modifier and Type	Method and Description
static Stream<String>	flatMatches(Stream<String> stream, Pattern pattern) Takes stream, finds matches in each element of the stream according to the given pattern and provides all matches in a single stream returned as the result.
static Stream<String>	flatMatches(Stream<String> stream, String pattern) Takes stream, finds matches in each element of the stream according to the given pattern and provides all matches in a single stream returned as the result. This method is a wrapper around flatMatches(Stream, Pattern) first compiling the parameter pattern to a Pattern object then delegating to the wrapped function.
static Stream<String>	flatSplit(Stream<? extends CharSequence> stream, Pattern pattern) Splitting the elements of the given stream by the given pattern and returning a single stream of all results of the splits.
static Stream<String>	flatSplit(Stream<? extends CharSequence> stream, Pattern pattern, int limit) Splitting the elements of the given stream by the given pattern and returning a single stream of all results of the splits.
static Stream<String>	flatSplit(Stream<? extends CharSequence> stream, String pattern) Splitting the elements of the given stream by the given pattern and returning a single stream of all results of the splits.
static Stream<String>	flatSplit(Stream<? extends CharSequence> stream, String pattern, int limit) Splitting the elements of the given stream by the given pattern and returning a single stream of all results of the splits.
static String	join(Stream<? extends CharSequence> stream) Shortcut for stream.collect(Collectors.joining()).
static String	join(Stream<? extends CharSequence> stream, CharSequence delimiter) Shortcut for stream.collect(Collectors.joining(delimiter)).
static String	join(Stream<? extends CharSequence> stream, CharSequence delimiter, CharSequence prefix, CharSequence suffix) Shortcut for stream.collect(Collectors.joining(delimiter,prefix)).
static <S extends CharSequence> Stream<S>	matching(Stream<S> stream, Pattern pattern) Filtering the given stream by elements matching the given pattern.
static <S extends CharSequence> Stream<S>	matching(Stream<S> stream, String pattern) Filtering the given stream by elements matching the given pattern. This method is a wrapper calling matching(Stream, Pattern) by compiling the given String pattern to a Pattern object before the call.

Methods inherited from class java.lang.Object

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

Method Detail

join

public static String join(Stream<? extends CharSequence> stream)

Shortcut for stream.collect(Collectors.joining()).

Parameters:

stream - the stream of character sequences to concatenate.

Returns:

concatenated string of all character sequences in stream

See Also:

Collectors.joining()

join

public static String join(Stream<? extends CharSequence> stream,
                          CharSequence delimiter)

Shortcut for stream.collect(Collectors.joining(delimiter)).

Parameters:

stream - the stream of character sequences to concatenate.

delimiter - will be used in between each element in stream

Returns:

concatenated string of all character sequences in stream with delimiter as separator between elements.

See Also:

Collectors.joining(CharSequence)

join

public static String join(Stream<? extends CharSequence> stream,
                          CharSequence delimiter,
                          CharSequence prefix,
                          CharSequence suffix)

Shortcut for stream.collect(Collectors.joining(delimiter,prefix)).

Parameters:

stream - the stream of character sequences to concatenate.

delimiter - will be used in between each element in stream

prefix - will be prepended to the concatenated elements of stream.

suffix - fill be postpended after the concatenated elements of stream.

Returns:

concatenated string of all character sequences in stream

See Also:

Collectors.joining(CharSequence,CharSequence,CharSequence)

matching

public static <S extends CharSequence> Stream<S> matching(Stream<S> stream,
                                                          String pattern)

Filtering the given stream by elements matching the given pattern.
This method is a wrapper calling matching(Stream, Pattern) by compiling the given String pattern to a Pattern object before the call.

Type Parameters:

S - Type extending CharSequence elements in stream are instance of

Parameters:

stream - stream to be filtered to only contain elements matching the given pattern

pattern - the regex pattern to filter element in stream by.

Returns:

stream filtered by the given pattern.

matching

public static <S extends CharSequence> Stream<S> matching(Stream<S> stream,
                                                          Pattern pattern)

Filtering the given stream by elements matching the given pattern.

Type Parameters:

S - Type extending CharSequence elements in stream are instance of

Parameters:

stream - stream to be filtered to only contain elements matching the given pattern

pattern - the regex pattern to filter element in stream by.

Returns:

stream filtered by the given pattern.

flatSplit

public static Stream<String> flatSplit(Stream<? extends CharSequence> stream,
                                       String pattern)

Splitting the elements of the given stream by the given pattern and returning a single stream of all results of the splits. This can e.g. be useful to split the content of a file into words:

 
 	Files.lines(Paths.get("text.txt"))
       .flatSplit("\\s+")
 

This method is a wrapper around flatSplit(Stream, Pattern) first compiling the parameter pattern to a Pattern object then delegating to the wrapped function.

Parameters:

stream - the stream to be split elements using pattern

pattern - the pattern used to split elements in stream

Returns:

stream of all results of the splits of all elements in stream using pattern

flatSplit

public static Stream<String> flatSplit(Stream<? extends CharSequence> stream,
                                       Pattern pattern)

Splitting the elements of the given stream by the given pattern and returning a single stream of all results of the splits. Note that the result will. This can e.g. be useful to split the content of a file into words:

 
 	Files.lines(Paths.get("text.txt"))
       .flatSplit("\\s+")
 

Parameters:

stream - the stream to be split elements using pattern

pattern - the pattern used to split elements in stream

Returns:

stream of all results of the splits of all elements in stream using pattern

flatSplit

public static Stream<String> flatSplit(Stream<? extends CharSequence> stream,
                                       String pattern,
                                       int limit)

Splitting the elements of the given stream by the given pattern and returning a single stream of all results of the splits. The maximum number of elements produced by a split can be set via the limit parameter. It follows the semantics of the String.split(String,int) method, so negative values will result in no limit in split elements and a value of 0 leads to an unlimited amount of split elements, but will drop trailing empty strings.
This method is a wrapper around flatSplit(Stream, Pattern, int) first compiling the parameter pattern to a Pattern object then delegating to the wrapped function.

Parameters:

stream - the stream to be split elements using pattern

pattern - the pattern used to split elements in stream

limit - limits the amount of elements in which stream elements are split into, according to the rules above

Returns:

stream of all results of the splits of all elements in stream using pattern

flatSplit

public static Stream<String> flatSplit(Stream<? extends CharSequence> stream,
                                       Pattern pattern,
                                       int limit)

Splitting the elements of the given stream by the given pattern and returning a single stream of all results of the splits. The maximum number of elements produced by a split can be set via the limit parameter. It follows the semantics of the String.split(String,int) method, so negative values will result in no limit in split elements and a value of 0 leads to an unlimited amount of split elements, but will drop trailing empty strings.

Parameters:

stream - the stream to be split elements using pattern

pattern - the pattern used to split elements in stream

limit - limits the amount of elements in which stream elements are split into, according to the rules above

Returns:

stream of all results of the splits of all elements in stream using pattern

flatMatches

public static Stream<String> flatMatches(Stream<String> stream,
                                         Pattern pattern)

Takes stream, finds matches in each element of the stream according to the given pattern and provides all matches in a single stream returned as the result.

Parameters:

stream - elements which are searched for matches according to pattern

pattern - to find matches in elements of stream

Returns:

stream containing all matches in input stream according to pattern

flatMatches

public static Stream<String> flatMatches(Stream<String> stream,
                                         String pattern)

Takes stream, finds matches in each element of the stream according to the given pattern and provides all matches in a single stream returned as the result.
This method is a wrapper around flatMatches(Stream, Pattern) first compiling the parameter pattern to a Pattern object then delegating to the wrapped function.

Parameters:

stream - elements which are searched for matches according to pattern

pattern - to find matches in elements of stream

Returns:

stream containing all matches in input stream according to pattern