Java tutorial
//package com.java2s; public class Main { public static long sizeFromMToLong(String sizeString) { long size = 0; if (sizeString.endsWith("M")) { sizeString = sizeString.substring(0, sizeString.length() - 1); size = (long) ((Double.valueOf(sizeString)) * 1024 * 1024); } else if (sizeString.endsWith("K")) { sizeString = sizeString.substring(0, sizeString.length() - 1); size = (long) ((Double.valueOf(sizeString)) * 1024); } return size; } }