Srt2Vtt.java

package srt2vtt;

import java.io.*;

public class Srt2Vtt {
	enum State { Number, TimeStamp, Text };
	
	public void convert(Reader srt, Writer vtt) throws IOException {
		BufferedReader br = new BufferedReader(srt);
		String line;
		vtt.write("WEBVTT\n\n");
		State state=State.Number;
		
		while((line = br.readLine())!=null){
			switch(state) {
				case Number:
					state=State.TimeStamp;
					break;
				case TimeStamp:
					vtt.write(line.replace(',', '.')+"\n");
					state=State.Text;
					break;
				case Text:
					vtt.write(line+"\n");
					if( line.length()==0)
						state=State.Number;
					break;
			}
		}
		vtt.close();
		srt.close();
	}
	
	public static void main(String[] args) throws IOException {
		Srt2Vtt s2v = new Srt2Vtt();
		s2v.convert(new FileReader("test.srt"), new PrintWriter( System.out));
	}
}