1 /* 2 * $Id: VelocityUtil.java 1306435 2012-03-28 15:39:11Z nlebas $ 3 * 4 * Licensed to the Apache Software Foundation (ASF) under one 5 * or more contributor license agreements. See the NOTICE file 6 * distributed with this work for additional information 7 * regarding copyright ownership. The ASF licenses this file 8 * to you under the Apache License, Version 2.0 (the 9 * "License"); you may not use this file except in compliance 10 * with the License. You may obtain a copy of the License at 11 * 12 * http://www.apache.org/licenses/LICENSE-2.0 13 * 14 * Unless required by applicable law or agreed to in writing, 15 * software distributed under the License is distributed on an 16 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY 17 * KIND, either express or implied. See the License for the 18 * specific language governing permissions and limitations 19 * under the License. 20 */ 21 22 package org.apache.tiles.request.velocity.autotag; 23 24 import java.util.Map; 25 26 import org.apache.velocity.context.InternalContextAdapter; 27 import org.apache.velocity.runtime.parser.node.ASTMap; 28 import org.apache.velocity.runtime.parser.node.Node; 29 30 /** 31 * Utilities for Velocity usage in Tiles. 32 * 33 * @version $Rev: 1306435 $ $Date: 2012-03-29 02:39:11 +1100 (Thu, 29 Mar 2012) $ 34 */ 35 public final class VelocityUtil { 36 37 /** 38 * Private constructor to avoid instantiation. 39 */ 40 private VelocityUtil() { 41 } 42 43 /** 44 * Extracts the parameters from the directives, by getting the child at 45 * position 0 supposing it is a map. 46 * 47 * @param context The Velocity context. 48 * @param node The node to use. 49 * @return The extracted parameters. 50 */ 51 @SuppressWarnings("unchecked") 52 public static Map<String, Object> getParameters(InternalContextAdapter context, 53 Node node) { 54 ASTMap astMap = (ASTMap) node.jjtGetChild(0); 55 Map<String, Object> params = (Map<String, Object>) astMap 56 .value(context); 57 return params; 58 } 59 60 /** 61 * Returns the "value" parameter if it is not null, otherwise returns 62 * "defaultValue". 63 * 64 * @param value The value to return, if it is not null. 65 * @param defaultValue The value to return, if <code>value</code> is null. 66 * @return The value, defaulted if necessary. 67 */ 68 public static Object getObject(Object value, Object defaultValue) { 69 if (value == null) { 70 value = defaultValue; 71 } 72 return value; 73 } 74 }