Here you can find the source of toUpperCase(char ch)
public static char toUpperCase(char ch)
//package com.java2s; //License from project: Open Source License public class Main { public static char toUpperCase(char ch) { StringBuffer sb = new StringBuffer(); sb.append(ch);/*ww w . j av a 2 s. c o m*/ char[] arr = sb.toString().toUpperCase().toCharArray(); return arr[0]; } }