Simple program to tail a log file

Recently I came across a requirement to develop a a logging program that tails the log file, similar to a tail log program. I need to tail the specific number of lines of a log file. After some research I decided to go with RandomAccessFile method of getting the check the last number of lines. Then I need something to keep on reading the log file and print it out. Try to use RandomAccessFile but it keeps locking the log file and unable to read it in real time. Then I try the BufferedReader with threading approach although the end result of printing out the output is there will be an extra new line as it prints out the values in the console.
Tried to resolve this extra new line but can't find any solution to it. Anyway the code is as below.


public class Tailog implements Runnable {
boolean execute = true;
BufferedInputStream reader;
BufferedReader in;
File file;
RandomAccessFile raf;
InputStreamReader inputStreamReader;
BufferedReader bufferedReader;
PrintWriter pwriter;
public Tailog() {
}
public Tailog(long numLine, String fileName, PrintWriter pw) {
try {
file = new File(fileName);
try {
//get last n lines
raf = new RandomAccessFile(file, "rw");
List<Long> seekPosi = new ArrayList<Long>();
long fileLength = file.length();
long tailrow = 0;
for (long i = fileLength - 2; i >= 0; i--) {
raf.seek(i);
String readLine = raf.readLine();


if (readLine.equals("")) {
seekPosi.add(i - 1);
tailrow++;
i--;
}
if (tailrow == numLine)
break;
}


Collections.sort(seekPosi);
for (long x : seekPosi) {
raf.seek(x + 2);
String printLine = raf.readLine();
pw.println(printLine);


}
raf.close();
} catch (FileNotFoundException e) {
e.printStackTrace();
}


// start read line by line
inputStreamReader = new InputStreamReader(new FileInputStream(
fileName));
bufferedReader = new BufferedReader(inputStreamReader);
String line = bufferedReader.readLine();
while (line != null) {
line = bufferedReader.readLine();
}
pwriter = pw;
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}


public void run() {
while (execute) {
try {
String line = bufferedReader.readLine();
if (line != null) {
pwriter.println(line);
pwriter.flush();
} else {
try {
Thread.sleep(500);
} catch (InterruptedException ex) {
execute = false;
}
}


} catch (Exception e) {
e.printStackTrace();
}
}
}


public static void main(String[] args) throws Exception {
PrintWriter pw = new PrintWriter(System.out, true);
String numLineStr = "";
String fileName = "";
try {
numLineStr = args[0];
fileName = args[1];
} catch (Exception e) {
e.printStackTrace();
}

long numLine = 0;
try {
numLine = Long.parseLong(numLineStr);
File file = new File(fileName);
if(file.exists()){
Tailog tailog = new Tailog(numLine, fileName, pw);
tailog.run();
}
else{
pw.println("Please specify correct file name: eg C:/server/log/server.log");
}
} catch (Exception e) {
e.printStackTrace();
pw.println("Please specify correct command: java -jar Tailog.jar <number of lines> <file name>");
}
}
}