Pattern.matcher doesnt throw NullPointerException

gistfile1.java

public long serializeTimestamp(String timeConfigFile, String key){
      FileReader reader = null;
	    BufferedReader r = null;
	    FileWriter fw = null;
		try {
			reader = new FileReader(new File(timeConfigFile));
			r = new BufferedReader(reader);
			String line = r.readLine();
			Pattern pattern = Pattern.compile("^"+key+"(\\d*)$");
			Matcher matcher = pattern.matcher(line);
			matcher.find();
			long lastRun = Long.parseLong(matcher.group(1));
			log.debug(lastRun);
			long now = System.currentTimeMillis();
			fw = new FileWriter(new File(timeConfigFile));
			System.out.println("fw: "+fw);
			fw.write(key+String.valueOf(now));
			return lastRun;
		} catch (FileNotFoundException e) {
			e.printStackTrace();
			//log.error("timeConfigFile file cannot be found", e);
		} catch (IOException e) {
			e.printStackTrace();
		} finally {
			try {
				reader.close();
				r.close();
				log.debug("get called before it returns!!!");
				log.debug("fw: "+fw);
				fw.close();
			} catch (IOException e) {
				e.printStackTrace();
			}
			
		}
		return 0;
	}