| /* |
| * 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.creadur.tentacles; |
| |
| import java.io.File; |
| import java.io.IOException; |
| import java.io.InputStreamReader; |
| import java.io.StringWriter; |
| import java.io.Writer; |
| import java.net.URL; |
| import java.util.HashMap; |
| import java.util.Map; |
| import java.util.Properties; |
| |
| import org.apache.velocity.VelocityContext; |
| import org.apache.velocity.app.VelocityEngine; |
| import org.apache.velocity.runtime.log.CommonsLogLogChute; |
| |
| public final class Templates { |
| |
| private static final Templates INSTANCE = new Templates(); |
| |
| private final VelocityEngine engine; |
| |
| private Templates() { |
| Properties properties = new Properties(); |
| properties.setProperty("file.resource.loader.cache", "true"); |
| properties.setProperty("resource.loader", "file, class"); |
| properties.setProperty("class.resource.loader.description", "Velocity Classpath Resource Loader"); |
| properties.setProperty("class.resource.loader.class", "org.apache.velocity.runtime.resource.loader.ClasspathResourceLoader"); |
| properties.setProperty("runtime.log.logsystem.class", CommonsLogLogChute.class.getName()); |
| properties.setProperty("runtime.log.logsystem.commons.logging.name", Templates.class.getName()); |
| |
| engine = new VelocityEngine(); |
| engine.init(properties); |
| } |
| |
| private void evaluate(String template, Map<String, Object> mapContext, Writer writer) throws IOException { |
| |
| URL resource = Thread.currentThread().getContextClassLoader().getResource(template); |
| |
| if (resource == null) throw new IllegalStateException(template); |
| |
| VelocityContext context = new VelocityContext(mapContext); |
| engine.evaluate(context, writer, Templates.class.getName(), new InputStreamReader(resource.openStream())); |
| } |
| |
| public static Builder template(String name) { |
| return INSTANCE.new Builder(name); |
| } |
| |
| public class Builder { |
| private final String template; |
| private final Map<String, Object> map = new HashMap<String, Object>(); |
| |
| public Builder(String template) { |
| this.template = template; |
| } |
| |
| public Builder add(String key, Object value) { |
| map.put(key, value); |
| return this; |
| } |
| |
| public Builder addAll(Map<String, Object> map) { |
| this.map.putAll(map); |
| return this; |
| } |
| |
| public String apply() { |
| final StringWriter writer = new StringWriter(); |
| |
| try { |
| evaluate(template, map, writer); |
| } catch (IOException ioe) { |
| throw new RuntimeException("can't apply template " + template, ioe); |
| } |
| |
| return writer.toString(); |
| } |
| |
| public File write(File file) throws IOException { |
| IO.writeString(file, apply()); |
| return file; |
| } |
| } |
| } |