How to remove characters/lines from the beginning of an InputStream

Question

Hi,
I have a program which receives several InputStreams. From each of these streams I have to remove 2 lines from the beginning. After the lines are removed, all the streams are combined to one with SequenceInputStream and read in one chunk. Is there an easy/simple way of doing this?
One option I thought would be to read the char by char until 2 end of line chars have been detected and then read the rest of the data to a buffer. And the create a ByteArrayInputStream out of this buffer. Problem with this approach is, that the amount of data can be large, so putting all the data in to memory might cause problems.
Another option is to use BufferredInputStream and use the readline() method twice to get rid of the lines that are not needed. After this I would write the data to some output stream, which is then converted back to input stream. Propably would work, but sound too much of work for a simple thing like this. There has to be better way.
To make it simple, what I need is a method that looks like the following, or something similar
*  Removes n number of lines from the beginning of a InputStream.
*  @param is InputStream where the lines are removed
*  @param numberOfLines int value to indicate how many lines whould be removed
*  @return InputStream where lines have been removed.
public InputStream removeLines(InputStream is, numberOfLines);Thanks.

Answer 1

Here's the code, feel free to use it. Comments are also welcome.
public InputStream removeLinesFromTheBeginning(InputStream is, int numberOfLines) throws IOException
          char c = 'c';
          int i = 0;
          for(int n = 0 ; n < numberOfLines ; n++)
               do
                    c = (char)is.read();
                    System.out.print(c);
                    if(c == (char)-1)     // end of stream reached before any newline characters were found.
                         return null;
                    i++;
               while(c != '\n');
               System.out.println();
               System.out.println("Characters removed:" + i);
               System.out.println("n: " + n);
               i = 0;
          return is;
     }Edited by: dave_spaghetti on Jun 16, 2009 5:42 AM
Fixed a bug.