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Apply Regular Expressions on the contents of a file

import java.io.FileInputStream; import java.nio.ByteBuffer; import java.nio.CharBuffer; import java.nio.channels.FileChannel; import java.nio.charset.Charset; import java.util.regex.Matcher; import java.util.regex.Pattern; public class Main {   public static void main(String[] argv) throws Exception {     Pattern pattern = Pattern.compile("pattern");     FileInputStream input = new FileInputStream("file.txt");     FileChannel channel = input.getChannel();     ByteBuffer bbuf = channel.map(FileChannel.MapMode.READ_ONLY, 0, (int) channel.size());     CharBuffer cbuf = Charset.forName("8859_1").newDecoder().decode(bbuf);     Matcher matcher = pattern.matcher(cbuf);     while (matcher.find()) {       String match = matcher.group();       System.out.println(match);     }   } }