Strftime.java
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.catalina.util;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.Locale;
import java.util.Properties;
import java.util.TimeZone;
/**
* Converts dates to strings using the same format specifiers as strftime Notes:
* <ul>
* <li>This does not mimic strftime perfectly. Certain strftime commands, are not supported, and will convert as if they
* were literals.</li>
* <li>Certain complicated commands, like those dealing with the week of the year probably don't have exactly the same
* behavior as strftime.</li>
* <li>These limitations are due to use SimpleDateTime. If the conversion was done manually, all these limitations could
* be eliminated.</li>
* <li>The interface looks like a subset of DateFormat. Maybe someday someone will make this class extend
* DateFormat.</li>
* </ul>
*
* @author Bip Thelin
* @author Dan Sandberg
*/
public class Strftime {
protected static final Properties translate;
protected final SimpleDateFormat simpleDateFormat;
/*
* Initialize our pattern translation
*/
static {
translate = new Properties();
translate.put("a", "EEE");
translate.put("A", "EEEE");
translate.put("b", "MMM");
translate.put("B", "MMMM");
translate.put("c", "EEE MMM d HH:mm:ss yyyy");
// There's no way to specify the century in SimpleDateFormat. We don't want to hard-code
// 20 since this could be wrong for the pre-2000 files.
// translate.put("C", "20");
translate.put("d", "dd");
translate.put("D", "MM/dd/yy");
translate.put("e", "dd"); // will show as '03' instead of ' 3'
translate.put("F", "yyyy-MM-dd");
translate.put("g", "yy");
translate.put("G", "yyyy");
translate.put("H", "HH");
translate.put("h", "MMM");
translate.put("I", "hh");
translate.put("j", "DDD");
translate.put("k", "HH"); // will show as '07' instead of ' 7'
translate.put("l", "hh"); // will show as '07' instead of ' 7'
translate.put("m", "MM");
translate.put("M", "mm");
translate.put("n", "\n");
translate.put("p", "a");
translate.put("P", "a"); // will show as pm instead of PM
translate.put("r", "hh:mm:ss a");
translate.put("R", "HH:mm");
// There's no way to specify this with SimpleDateFormat
// translate.put("s","seconds since epoch");
translate.put("S", "ss");
translate.put("t", "\t");
translate.put("T", "HH:mm:ss");
// There's no way to specify this with SimpleDateFormat
// translate.put("u","day of week ( 1-7 )");
// There's no way to specify this with SimpleDateFormat
// translate.put("U","week in year with first Sunday as first day...");
translate.put("V", "ww"); // I'm not sure this is always exactly the same
// There's no way to specify this with SimpleDateFormat
// translate.put("W","week in year with first Monday as first day...");
// There's no way to specify this with SimpleDateFormat
// translate.put("w","E");
translate.put("X", "HH:mm:ss");
translate.put("x", "MM/dd/yy");
translate.put("y", "yy");
translate.put("Y", "yyyy");
translate.put("Z", "z");
translate.put("z", "Z");
translate.put("%", "%");
}
/**
* Create an instance of this date formatting class
*
* @param origFormat the strftime-style formatting string
* @param locale the locale to use for locale-specific conversions
*/
public Strftime(String origFormat, Locale locale) {
String convertedFormat = convertDateFormat(origFormat);
simpleDateFormat = new SimpleDateFormat(convertedFormat, locale);
}
/**
* Format the date according to the strftime-style string given in the constructor.
*
* @param date the date to format
*
* @return the formatted date
*/
public String format(Date date) {
return simpleDateFormat.format(date);
}
/**
* Get the timezone used for formatting conversions
*
* @return the timezone
*/
public TimeZone getTimeZone() {
return simpleDateFormat.getTimeZone();
}
/**
* Change the timezone used to format dates
*
* @param timeZone The new time zone
*
* @see SimpleDateFormat#setTimeZone
*/
public void setTimeZone(TimeZone timeZone) {
simpleDateFormat.setTimeZone(timeZone);
}
/**
* Search the provided pattern and get the C standard Date/Time formatting rules and convert them to the Java
* equivalent.
*
* @param pattern The pattern to search
*
* @return The modified pattern
*/
protected String convertDateFormat(String pattern) {
boolean inside = false;
boolean mark = false;
boolean modifiedCommand = false;
StringBuilder buf = new StringBuilder();
for (int i = 0; i < pattern.length(); i++) {
char c = pattern.charAt(i);
if (c == '%' && !mark) {
mark = true;
} else {
if (mark) {
if (modifiedCommand) {
// don't do anything--we just wanted to skip a char
modifiedCommand = false;
mark = false;
} else {
inside = translateCommand(buf, pattern, i, inside);
// It's a modifier code
if (c == 'O' || c == 'E') {
modifiedCommand = true;
} else {
mark = false;
}
}
} else {
if (!inside && c != ' ') {
// We start a literal, which we need to quote
buf.append('\'');
inside = true;
}
buf.append(c);
}
}
}
if (buf.length() > 0) {
char lastChar = buf.charAt(buf.length() - 1);
if (lastChar != '\'' && inside) {
buf.append('\'');
}
}
return buf.toString();
}
protected String quote(String str, boolean insideQuotes) {
String retVal = str;
if (!insideQuotes) {
retVal = '\'' + retVal + '\'';
}
return retVal;
}
/**
* Try to get the Java Date/Time formatting associated with the C standard provided.
*
* @param buf The buffer
* @param pattern The date/time pattern
* @param index The char index
* @param oldInside Flag value
*
* @return True if new is inside buffer
*/
protected boolean translateCommand(StringBuilder buf, String pattern, int index, boolean oldInside) {
char firstChar = pattern.charAt(index);
boolean newInside = oldInside;
// O and E are modifiers, they mean to present an alternative representation of the next char
// we just handle the next char as if the O or E wasn't there
if (firstChar == 'O' || firstChar == 'E') {
if (index + 1 < pattern.length()) {
newInside = translateCommand(buf, pattern, index + 1, oldInside);
} else {
buf.append(quote("%" + firstChar, oldInside));
}
} else {
String command = translate.getProperty(String.valueOf(firstChar));
// If we don't find a format, treat it as a literal--That's what apache does
if (command == null) {
buf.append(quote("%" + firstChar, oldInside));
} else {
// If we were inside quotes, close the quotes
if (oldInside) {
buf.append('\'');
}
buf.append(command);
newInside = false;
}
}
return newInside;
}
}