Concat stream lines before collecting them

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Simply, the code below produces a stream of five lines, I need to concat these lines into one line (while streaming) for further use and before collecting them.The code is about to convert a character string into one long binary string

Stream<String> binText = "hello".chars()
    .mapToObj(x-> Integer.toBinaryString(x))
    .map(x-> String.format("%8s", x).replaceAll(" ", "0"));

I'm a bit new for the term of "Stream API", so any suggestion would be appreciated.

Update: Let say I want map the stream from the above code into int [] of 0 and 1, actually, I tried the below code and it works fine but it seems not efficient and need to be normalized

int [] binText = "hello".chars()
                     .mapToObj(x-> Integer.toBinaryString(x))
                     .map(x-> String.format("%8s", x).replaceAll(" ", "0"))
                     .flatMap(s-> Stream.of(s.split("")))
                     .mapToInt(Integer::parseInt)
                     .toArray();   

isn't it ?

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There are 1 answers

4
Naman On

What you are looking for is a collector to join those strings and you would have

.collect(Collectors.joining())

eventually the complete solution could be:

String binText = "hello".chars()
        .mapToObj(Integer::toBinaryString)
        .map(x-> String.format("%8s", x).replace(" ", "0"))
        .collect(Collectors.joining());