Here you can find the source of toUpperCase(char input)
public static char toUpperCase(char input)
//package com.java2s; //License from project: Apache License public class Main { public static char toUpperCase(char input) { if (input >= 'a' && input <= 'z') { input -= 32;/*from w ww . j a v a 2s. c om*/ } return input; } }