java file input with rewind()/reset() capability

Question

I need to write a function that takes in some kind of input stream thing (e.g. an InputStream or a FileChannel) in order to read a large file in two passes: once to precompu

Answer 1

If you get the associated FileChannel from the FileInputStream, you can use the position method to set the file pointer to anywhere in the file.

FileInputStream fis = new FileInputStream("/etc/hosts");
FileChannel     fc = fis.getChannel();


fc.position(100);// set the file pointer to byte position 100;