Java tutorial
/* * ELW : e-learning workspace * Copyright (C) 2010 Anton Kraievoy * * This program is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation, either version 3 of the License, or * (at your option) any later version. * * This program 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 General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program. If not, see <http://www.gnu.org/licenses/>. */ package elw.web; import elw.miniweb.ViewJackson; import elw.vo.Format; import org.joda.time.DateTime; import org.joda.time.Period; import org.joda.time.format.DateTimeFormat; import org.joda.time.format.DateTimeFormatter; import org.joda.time.format.PeriodFormatter; import org.joda.time.format.PeriodFormatterBuilder; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import java.io.IOException; import java.util.*; /** * Inspired by @link{org.apache.velocity.tools.generic.FormatTool}, but has more specific and fine-tuned methods. */ public class FormatTool implements Format { private static final Logger log = LoggerFactory.getLogger(FormatTool.class); private final static Map<Locale, FormatTool> cache = new HashMap<Locale, FormatTool>(); private static final long KB = 1024; private static final long HALF_KB = 512; private static final long MB = KB * KB; private static final long HALF_MB = HALF_KB * KB; private static final long MB_BOUNDARY = 10 * MB; private static final long KB_BOUNDARY = 10 * KB; private final Locale locale; private final Map<String, DateTimeFormatter> dtfCache = new TreeMap<String, DateTimeFormatter>(); private final Map<String, PeriodFormatter> pfCache = new TreeMap<String, PeriodFormatter>(); private String pattern = "MMM d"; private String patternWeek = "EEE d HH:mm"; private String patternToday = "HH:mm"; public static final String MODEL_KEY = "f"; private FormatTool(Locale locale) { this.locale = locale; } public static FormatTool forLocale(final Locale locale) { synchronized (cache) { final FormatTool cached = cache.get(locale); if (cached != null) { return cached; } final FormatTool created = new FormatTool(locale); cache.put(locale, created); return created; } } public void setPattern(String pattern) { this.pattern = pattern; } public void setPatternToday(String patternToday) { this.patternToday = patternToday; } public void setPatternWeek(String patternWeek) { this.patternWeek = patternWeek; } @SuppressWarnings({ "UnusedDeclaration" }) public String formatSize(long size) { if (size < 0) { return ""; } if (size >= MB_BOUNDARY) { return Long.toString((size + HALF_MB) / MB) + " MB "; } else if (size >= KB_BOUNDARY) { return Long.toString((size + HALF_KB) / KB) + " KB "; } else { return Long.toString(size) + " bytes "; } } public String format(Date date) { if (date == null) { return ""; } return format(date.getTime(), pattern, patternWeek, patternToday); } public String format(final long dateLong) { return format(dateLong, pattern, patternWeek, patternToday); } public String format(Date date, String pattern) { return format(date, pattern, pattern, pattern); } public String format(long dateLong, String pattern) { return format(dateLong, pattern, pattern, pattern); } public String format(Date date, String pattern, String patternWeek, String patternToday) { if (date == null) { return ""; } return format(date.getTime(), pattern, patternWeek, patternToday); } public String format(final long dateLong, String pattern, String patternWeek, String patternToday) { final DateTimeFormatter formatter = lookupFormatter(pattern); final DateTimeFormatter formatterToday = lookupFormatter(patternToday); final DateTimeFormatter formatterWeek = lookupFormatter(patternWeek); final DateTime now = new DateTime(System.currentTimeMillis()); final DateTime midnight = new DateTime(now.getYear(), now.getMonthOfYear(), now.getDayOfMonth(), 0, 0, 0, 0); if (midnight.isBefore(dateLong) && midnight.plusDays(1).isAfter(dateLong)) { return formatterToday.print(dateLong); } else if (now.minusDays(7).isBefore(dateLong) && now.plusDays(7).isAfter(dateLong)) { return formatterWeek.print(dateLong); } else { return formatter.print(dateLong); } } private DateTimeFormatter lookupFormatter(String pattern) { synchronized (dtfCache) { final DateTimeFormatter cached = dtfCache.get(pattern); if (cached != null) { return cached; } final DateTimeFormatter created = DateTimeFormat.forPattern(pattern).withLocale(locale); dtfCache.put(pattern, created); return created; } } private PeriodFormatter lookupPeriodFormatter(String pattern) { synchronized (dtfCache) { final PeriodFormatter cached = pfCache.get(pattern); if (cached != null) { return cached; } final PeriodFormatter created = createDefaultPeriodFormatted(pattern).withLocale(locale); pfCache.put(pattern, created); return created; } } private static PeriodFormatter createDefaultPeriodFormatted(String pattern) { String[] variants = { " ", ",", ",and ", ", and " }; final PeriodFormatter formatter; if ("y".equals(pattern)) { formatter = new PeriodFormatterBuilder().printZeroRarelyLast().appendYears() .appendSuffix(" year", " years").toFormatter(); } else if ("M".equals(pattern)) { formatter = new PeriodFormatterBuilder().printZeroNever().appendYears().appendSuffix(" year", " years") .printZeroRarelyLast().appendMonths().appendSuffix(" month", " months").toFormatter(); } else if ("d".equals(pattern)) { formatter = new PeriodFormatterBuilder().printZeroNever().appendYears().appendSuffix(" year", " years") .appendSeparator(", ", " and ", variants).appendMonths().appendSuffix(" month", " months") .appendSeparator(", ", " and ", variants).printZeroRarelyLast().appendDays() .appendSuffix(" day", " days").toFormatter(); } else if ("H".equals(pattern)) { formatter = new PeriodFormatterBuilder().printZeroNever().appendYears().appendSuffix(" year", " years") .appendSeparator(", ", " and ", variants).appendMonths().appendSuffix(" month", " months") .appendSeparator(", ", " and ", variants).appendDays().appendSuffix(" day", " days") .appendSeparator(", ", " and ", variants).printZeroRarelyLast().appendHours() .appendSuffix(" hour", " hours").toFormatter(); } else if ("m".equals(pattern)) { formatter = new PeriodFormatterBuilder().printZeroNever().appendYears().appendSuffix(" year", " years") .appendSeparator(", ", " and ", variants).appendMonths().appendSuffix(" month", " months") .appendSeparator(", ", " and ", variants).appendDays().appendSuffix(" day", " days") .appendSeparator(", ", " and ", variants).appendHours().appendSuffix(" hour", " hours") .appendSeparator(", ", " and ", variants).printZeroRarelyLast().appendMinutes() .appendSuffix(" minute", " minutes").toFormatter(); } else if ("s".equals(pattern)) { formatter = new PeriodFormatterBuilder().printZeroNever().appendYears().appendSuffix(" year", " years") .appendSeparator(", ", " and ", variants).appendMonths().appendSuffix(" month", " months") .appendSeparator(", ", " and ", variants).appendDays().appendSuffix(" day", " days") .appendSeparator(", ", " and ", variants).appendHours().appendSuffix(" hour", " hours") .appendSeparator(", ", " and ", variants).appendMinutes().appendSuffix(" minute", " minutes") .appendSeparator(", ", " and ", variants).printZeroRarelyLast().appendSeconds() .appendSuffix(" second", " seconds").toFormatter(); } else { throw new IllegalArgumentException("pattern: '" + pattern + "'"); } return formatter; } @SuppressWarnings({ "UnusedDeclaration" }) public String formatAge(final Date time) { return formatAge(time.getTime()); } public String formatAge(final long timeMillis) { return formatDuration(System.currentTimeMillis() - timeMillis); } public String formatDuration(final long timeMillis) { final Period period = new Period(); final Period periodNorm = period.plusMillis((int) Math.abs(timeMillis)).normalizedStandard(); if (periodNorm.getYears() > 0) { return lookupPeriodFormatter("y").print(periodNorm); } else if (periodNorm.getMonths() > 0) { return lookupPeriodFormatter("M").print(periodNorm); } else if (periodNorm.getDays() > 0) { return lookupPeriodFormatter("d").print(periodNorm); } else if (periodNorm.getHours() > 0) { return lookupPeriodFormatter("H").print(periodNorm); } else if (periodNorm.getMinutes() > 0) { return lookupPeriodFormatter("m").print(periodNorm); } else { // LATER sometimes durations less than one second occur return lookupPeriodFormatter("s").print(periodNorm); } } public String json(final Object o) { try { return ViewJackson.MAPPER.writeValueAsString(o); } catch (IOException e) { if (o != null) { log.error("failed to render object of class: " + o.getClass().getSimpleName(), e); } else { log.error("failed to render null object", e); } return ""; } } private final String escSearches = "&\"\'><\r\n"; private final String[] escReplaces = { "&", """, "'", ">", "<", " ", " " }; public String esc(final String str) { if (str == null || str.length() == 0) { return ""; } final StringBuilder res = new StringBuilder(); for (int pos = 0; pos < str.length(); pos++) { final char strChr = str.charAt(pos); final int chrIdx = escSearches.indexOf(strChr); if (chrIdx < 0) { res.append(strChr); } else { res.append(escReplaces[chrIdx]); } } return res.toString(); } public String lines(final String text) { final StringBuilder res = new StringBuilder(text == null ? "" : text); int lineNo = 1; int lineStart = 0; final char[] padding = { ' ', ' ', ' ', ' ' }; do { final String strLineNo = Integer.toString(lineNo); res.insert(lineStart, ' '); res.insert(lineStart, lineNo); final int lineNoLen = strLineNo.length(); res.insert(lineStart, padding, 0, padding.length - lineNoLen); lineStart = Math.max(res.indexOf("\n", lineStart), res.indexOf("\r", lineStart + 1 + (Math.max(4, lineNoLen)))) + 1; lineNo += 1; } while (lineStart > 0); return res.toString(); } public String format2(final Double num) { return num != null ? org.akraievoy.base.Format.format2(num) : ""; } }