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javastreamreaderdatareader

Java make a copy of a reader

I have a BufferedReader looping through a file. When I hit a specific case, I would like to continue looping using a different instance of the reader but starting at this point.

Any ideas for a recommended solution? Create a separate reader, use the mark function, etc.?

Solution

  • While waiting for your answer to my comment, I'm stuck with making assumptions.

    If it's the linewise input you value, you may be as pleasantly surprised as I was to discover that RandomAccessFile now (since 1.4 or 1.5) supports the readLine method. Of course RandomAccessFile gives you fine-grained control over position.

    If you want buffered IO, you may consider wrapping a reader around a CharacterBuffer or maybe a ByteBuffer wrapped around a file mapped using the nio API. This gives you the ability to treat a file as memory, with fine control of the read pointer. And because the data is all in memory, buffering is included free of charge.