Java tutorial
/* * Copyright (C) 2014 the original author or authors. * * Licensed 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 ro.pippo.pebble; import java.util.Calendar; import java.util.Collections; import java.util.Date; import java.util.HashMap; import java.util.List; import java.util.Locale; import java.util.Map; import com.mitchellbosecke.pebble.extension.escaper.SafeString; import org.ocpsoft.prettytime.PrettyTime; import com.google.common.cache.CacheBuilder; import com.google.common.cache.CacheLoader; import com.google.common.cache.LoadingCache; import com.mitchellbosecke.pebble.extension.AbstractExtension; import com.mitchellbosecke.pebble.extension.Filter; import com.mitchellbosecke.pebble.template.EvaluationContext; public class PrettyTimeExtension extends AbstractExtension { private final LoadingCache<Locale, PrettyTime> prettyTimeCache; public PrettyTimeExtension() { this.prettyTimeCache = CacheBuilder.newBuilder().maximumSize(10) .build(new CacheLoader<Locale, PrettyTime>() { @Override public PrettyTime load(Locale locale) throws Exception { return new PrettyTime(locale); } }); } @Override public Map<String, Filter> getFilters() { Map<String, Filter> filters = new HashMap<>(); filters.put("prettyTime", new PrettyTimeFilter()); return filters; } public class PrettyTimeFilter implements Filter { @Override public List<String> getArgumentNames() { return Collections.emptyList(); } @Override public Object apply(Object input, Map<String, Object> args) { if (input == null) { return null; } EvaluationContext context = (EvaluationContext) args.get("_context"); Locale locale = context.getLocale(); String result = prettyTimeCache.getUnchecked(locale).format(getFormattableObject(input)); return new SafeString(result); } private Date getFormattableObject(Object value) { if (value instanceof Date) { return (Date) value; } else if (value instanceof Calendar) { return ((Calendar) value).getTime(); } else if (value instanceof Long) { return new Date((Long) value); } else { throw new RuntimeException("Formattable object for PrettyTime not found!"); } } } }