Here you can find the source of toInternalName(String className)
public static String toInternalName(String className)
//package com.java2s; // Licensed under the Apache License, Version 2.0 (the "License"); public class Main { public static String toInternalName(String className) { assert isNonBlank(className); return className.replace('.', '/'); }// w ww.j a va 2 s. c om public static boolean isNonBlank(String input) { return !isBlank(input); } public static boolean isBlank(String input) { return input == null || input.length() == 0 || input.trim().length() == 0; } }