| /* |
| * 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; |
| import org.apache.commons.text.StringSubstitutor; |
| |
| /** |
| * Formats the current date with the format given in the key in a format compatible with |
| * {@link java.text.SimpleDateFormat}. |
| * <p> |
| * Using a {@link StringLookup} from the {@link StringLookupFactory}: |
| * </p> |
| * |
| * <pre> |
| * StringLookupFactory.INSTANCE.dateStringLookup().lookup("yyyy-MM-dd"); |
| * </pre> |
| * <p> |
| * Using a {@link StringSubstitutor}: |
| * </p> |
| * |
| * <pre> |
| * StringSubstitutor.createInterpolator().replace("... ${date:yyyy-MM-dd} ...")); |
| * </pre> |
| * <p> |
| * The above examples convert {@code "yyyy-MM-dd"} to today's date, for example, {@code "2019-08-04"}. |
| * </p> |
| */ |
| 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); |
| } |
| } |