/* | |
* 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.commons.text.lookup; | |
import java.text.DateFormat; | |
import java.text.SimpleDateFormat; | |
import java.util.Date; | |
import org.apache.commons.lang3.time.FastDateFormat; | |
/** | |
* Formats the current date with the format given in the key in a format compatible with | |
* {@link java.text.SimpleDateFormat}. | |
*/ | |
final class DateStringLookup extends AbstractStringLookup { | |
/** | |
* Defines the singleton for this class. | |
*/ | |
static final DateStringLookup INSTANCE = new DateStringLookup(); | |
/** | |
* No need to build instances for now. | |
*/ | |
private DateStringLookup() { | |
// empty | |
} | |
/** | |
* Formats the given {@code date} long with the given {@code format}. | |
* | |
* @param date | |
* the date to format | |
* @param format | |
* the format string for {@link SimpleDateFormat}. | |
* @return the formatted date | |
*/ | |
private String formatDate(final long date, final String format) { | |
FastDateFormat dateFormat = null; | |
if (format != null) { | |
try { | |
dateFormat = FastDateFormat.getInstance(format); | |
} catch (final Exception ex) { | |
throw IllegalArgumentExceptions.format(ex, "Invalid date format: [%s]", format); | |
} | |
} | |
if (dateFormat == null) { | |
dateFormat = FastDateFormat.getInstance(); | |
} | |
return dateFormat.format(new Date(date)); | |
} | |
/** | |
* Formats the current date with the format given in the key in a format compatible with | |
* {@link java.text.SimpleDateFormat}. | |
* | |
* @param key | |
* the format to use. If null, the default {@link DateFormat} will be used. | |
* @return The value of the environment variable. | |
*/ | |
@Override | |
public String lookup(final String key) { | |
return formatDate(System.currentTimeMillis(), key); | |
} | |
} |