/* * File : $Source: /alkacon/cvs/alkacon/com.alkacon.opencms.v8.survey/src/com/alkacon/opencms/v8/survey/CmsAverageUtil.java,v $ * Date : $Date: 2010/03/19 15:31:14 $ * Version: $Revision: 1.2 $ * * This library is part of OpenCms - * the Open Source Content Management System * * Copyright (C) 2010 Alkacon Software (http://www.alkacon.com) * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * This library is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * For further information about Alkacon Software, please see the * company website: http://www.alkacon.com * * For further information about OpenCms, please see the * project website: http://www.opencms.org * * You should have received a copy of the GNU Lesser General Public * License along with this library; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ package com.alkacon.opencms.v8.survey; import java.util.ArrayList; import java.util.List; /** * A class providing utility functions for the "average bar" functionality of the survey * report.<p> * * @author Georg Westenberger * */ public class CmsAverageUtil { /** * Tries to parse a string as a "double" number and return it.<p> * * @param s the string that should be parsed * @return a Double object or null if the parsing failed */ public static Double parseDouble(String s) { try { return new Double(Double.parseDouble(s)); } catch (Exception e) { return null; } } /** * Tries to parse a string as a "Long" number and return it.<p> * * @param s the string that should be parsed * @return a Long object or null if the parsing failed */ public static Long parseLong(String s) { try { return new Long(Long.parseLong(s)); } catch (Exception e) { return null; } } /** * Given a list of Double objects, this method creates a new list of Double objects * by negating all the values from the input list.<p> * * For example, if the input list is [1, 2, -3], the result will be [-1, -2, 3]. * The input list is not modified. * * @param numbers the input list * @return the negated list of numbers */ public static List<Double> negateAll(List<Double> numbers) { List<Double> result = new ArrayList<Double>(); for (double number : numbers) { result.add(-number); } return result; } /** * From a "FieldDefault" specification used in form generator forms for e.g. * radio buttons, this method extracts all the numeric keys.<p> * * For example, if the input is "1:foo|2:bar|3|bar:qqq|xyzzy", then the list * [1, 2, 3] will be returned. * * @param fieldDefault The FieldDefault entry * @return the list of extracted numbers. */ public static List<Double> getNumbersFromDefault(String fieldDefault) { List<Double> result = new ArrayList<Double>(); String[] entries = fieldDefault.split("\\|"); for (String entry : entries) { int colonIndex = entry.indexOf(":"); if (colonIndex != -1) { entry = entry.substring(0, colonIndex); } Double d = parseDouble(entry); if (d != null) { result.add(d); } } return result; } /** * Finds the maximum from a list of Doubles.<p> * * If the list is empty, 0 is returned. * * @param numbers the list of Doubles * @return the maximum */ public static double getMax(List<Double> numbers) { if (numbers.size() == 0) { return 0.0; } double max = numbers.get(0); for (Double number : numbers) { max = Math.max(max, number); } return max; } /** * Finds the minimum from a list of Doubles.<p> * * If the list is empty, 0 is returned. * @param numbers the list of Doubles * @return the minimum */ public static double getMin(List<Double> numbers) { if (numbers.size() == 0) { return 0.0; } double min = numbers.get(0); for (Double number : numbers) { min = Math.min(min, number); } return min; } /** * Returns the difference between the maximum and the minimum of a list of Doubles.<p> * * @param numbers the input list * @return the range of the input list */ public static double getRange(List<Double> numbers) { return getMax(numbers) - getMin(numbers); } /** * Formats a ratio as a percentage.<p> * * For example, 0.362 will be formatted as "36.2%". * @param ratio the value that should be formatted as a percentage. * @return the input value formatted as a percentage. */ public static String asPercentage(double ratio) { return "" + (ratio * 100) + "%"; } /** * Returns a corrected bar split ratio by reserving a certain portion of the bar * as initial part that will always be displayed even if the split ratio is 0 (i.e. * the average equals the minimum value.<p> * * For example, if the split ratio is 0.5 and initialPart is 1/7, then the corrected * split ratio is 4/7. * * * @param initialPart the portion of the bar that should be reserved as the initial part * @param ratio the original split ratio * @return the corrected split ratio */ public static double getBarSplitRatio(double initialPart, double ratio) { return ((1 - initialPart) * ratio) + initialPart; } /** * This method does the same as getBarHtml, but reverses the orientation, * so that an average value equal to the minimum value will be displayed as * a full bar.<p> * * @see CmsAverageUtil#getBarHtml(String, String, String, String) * */ public static String getBarHtmlReverse(String fieldDefault, String averageStr, String displayStr, String color) { Double average = parseDouble(averageStr); if (average == null) { return "<!-- average is null -->"; } Double negAverage = new Double(-average.doubleValue()); List<Double> numbers = getNumbersFromDefault(fieldDefault); List<Double> negNumbers = negateAll(numbers); double range = getRange(negNumbers); if (range == 0) { return "<!-- range is 0 -->"; } double ratio = (negAverage - getMin(negNumbers)) / range; double correctedRatio = getBarSplitRatio(0.03, ratio); return makeBar(correctedRatio, displayStr, color); } /** * Returns the HTML for a bar showing the average value.<p> * * @param fieldDefault the FieldDefault entry * @param averageStr a string containing the average value * @param displayStr the string that should be displayed inside the bar. * @param color the color of the bar. * @return the HTML for the average bar. */ public static String getBarHtml(String fieldDefault, String averageStr, String displayStr, String color) { Double average = parseDouble(averageStr); if (average == null) { return "<!-- average is null -->"; } List<Double> numbers = getNumbersFromDefault(fieldDefault); double range = getRange(numbers); if (range == 0) { return "<!-- range is 0 -->"; } double ratio = (average - getMin(numbers)) / range; double correctedRatio = getBarSplitRatio(0.03, ratio); return makeBar(correctedRatio, displayStr, color); } /** * Helper method that actually creates the HTML for a bar.<p> * * @param ratio the width of the bar as a value between 0 and 1 * @param text the text to be displayed inside a bar * @param color the bar color * @return the HTML code for the bar. */ public static String makeBar(double ratio, String text, String color) { StringBuffer buffer = new StringBuffer(); buffer.append("<div class=\"reportitem\">"); buffer.append("<span class=\"processbar\">"); buffer.append("<span class=\"bar\" style=\"width:" + asPercentage(ratio) + "; background-color:" + color + "; color:#FFF;\" >" + text + "</span>"); buffer.append("</span>"); buffer.append("</div>"); return buffer.toString(); } }