Reading from System.in wrapped in a BufferedReader

Question

Suppose I want to read from the BufferedReader in which the System.in console is fed

 Charset charset = Charset.forName("UTF-8"); Reader reader = new InputStreamReader(System.in, charset); BufferedReader bufferedReader = new BufferedReader(reader);

1) how to correctly mark the end of reading from the console, so that the code goes further (for example, I enter "close", or press enter)

2) from reading you need to get a list of words that consist only of words and numbers

input:

 Мама мыла-мыла-мыла раму!

output

 [мама мыла мыла мыла раму]

Nofate ♦ 32.5k 13 55 86 · Accepted Answer · 2015-11-18T05:54:34

1) usually just have to wait for the end of the stream. In Unix, this is done using Ctrl + D , in DOS / Windows - Ctrl + Z. In addition, if you file a file at the program entrance, the end of the stream will occur when the file is over.

2) You can use regular expression and split . Here is an example of a complete implementation using Java 8:

 import java.io.BufferedReader; import java.io.InputStreamReader; import java.nio.charset.StandardCharsets; import java.util.List; import java.util.regex.Pattern; import java.util.stream.Collectors; public class ReadWords { public static void main(String[] args) { List<String> words = new BufferedReader( new InputStreamReader(System.in, StandardCharsets.UTF_8)).lines() .flatMap(Pattern.compile("[^\\p{L}\\p{Digit}]+")::splitAsStream) .filter(s -> !s.isEmpty()) .collect(Collectors.toList()); System.out.println(words); } }

The regular expression "[^\\p{L}\\p{Digit}]+" means "everything that is not numbers and letters." We use this as a separator, thus getting everything else. Filtering is needed to remove empty elements at the beginning of lines if the line does not begin with a letter / number.

Something in the console displays an empty sheet "[]", even if the encoding is removed.
Through the scanner without regulars and streams, too, does not output anything, somewhere the encoding settings got lost apparently. In Eclipse File - properties costs Cp1251 (Dafault ingerited from container), Os Windows
@ketchyn, did not think about Russian letters, \W only English matches.

Reading from System.in wrapped in a BufferedReader

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