apache commons io - Reading a specific line from a text file in Java -

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is there method read specific line text file ? in api or apache commons. :

string readline(file file, int linenumber)

i agree it's trivial implement, it's not efficient specially if file big.

string line = fileutils.readlines(file).get(linenumber);

would do, still has efficiency problem.

alternatively, can use:

 lineiterator = ioutils.lineiterator(        new bufferedreader(new filereader("file.txt")));  (int linenumber = 0; it.hasnext(); linenumber++) {     string line = (string) it.next();     if (linenumber == expectedlinenumber) {         return line;     }  }

this more efficient due buffer.

take @ scanner.skip(..) , attempt skipping whole lines (with regex). can't tell if more efficient - benchmark it.

p.s. efficiency mean memory efficiency


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