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
*
* Note: This does not mimic strftime perfectly. Certain strftime commands,
* are not supported, and will convert as if they were literals.
*
* Certain complicated commands, like those dealing with the week of the year
* probably don't have exactly the same behavior as strftime.
*
* These limitations are due to use SimpleDateTime. If the conversion was done
* manually, all these limitations could be eliminated.
*
* The interface looks like a subset of DateFormat. Maybe someday someone will make this class
* extend DateFormat.
*
* @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;
}
}