The Java utility class implements the Java fetch file line count

Utility class code to get the total number of lines, lines of code, comment lines, and blank lines of all Java files in the current project

import java.io.BufferedReader;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;
import java.io.Reader;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

public class JavaCode {
 private static final String PROJECT_DIR = "C:\test";
 private static int totle = 0;  //Total number of rows        
 private static int source  = 0;  //Lines of code & NBSP;    
 private static int blank  = 0;  //Blank lines & NBSP;      
 private static int comments = 0; //Comment lines

 
 private static void listNext(File dir) {
  File[] files = dir.listFiles();
  for (int i = 0; i < files.length; i++) {
   //Determine whether it is a folder, if it is a folder continue to retrieve down
   if (files[i].isDirectory()) {
    listNext(files[i]);
   } else {
    try {
     if (files[i].getName().endsWith(".java")) {
      System.out.println(files[i].getAbsolutePath());
      javaLine(files[i]);
     }
    }catch (Exception e) {
     e.printStackTrace();
    }
   }
  }
 }
 
 private static void javaLine(File f) throws FileNotFoundException, IOException{
  String strLine = "";
  String str = fromFile(f);
  if (str.length() > 0) {
   while (str.indexOf('n') != -1) {
    totle++;
    //System.out.println(totle);
    strLine = str.substring(0, str.indexOf('n')).trim();
    //str = str.substring(str.indexOf('n') + 1, str.length());
    if (strLine.length() == 0 ) {
     blank++;
    }else if (strLine.charAt(0) == '*' || strLine.charAt(0) == '/') {
     comments++;
    }else{
     source++;
     String regEx = "^*//";
     if(regEx(strLine,regEx)){
      comments++;
     }
    }
    str = str.substring(str.indexOf('n') + 1, str.length());
   }
  } 
 }

 
 private static String  fromFile(File f) throws FileNotFoundException,IOException {
  FileInputStream fis = new FileInputStream(f);
  byte[] b = new byte[(int) f.length()];
  fis.read(b);
  fis.close();
  return new String(b);
 }

 
 private static boolean regEx(String str,String regEx){
  Pattern p=Pattern.compile(regEx);
  Matcher m=p.matcher(str);
  boolean result=m.find();
  return result;
 }
 public static void main(String[] args) throws FileNotFoundException, IOException {
  //File root = new File(PROJECT_DIR);
  File directory = new File("");//Parameter is null
  //Get project path
  String projectFile = directory.getCanonicalPath() ;
  System.out.println(projectFile+"===============");
  listNext(new File(projectFile));
  System.out.println(totle+1);
  System.out.println(source);
  System.out.println(blank);
  System.out.println(comments);
 }
}