| /* |
| * 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.maven.model.interpolation; |
| |
| /* |
| * Copyright 2007 The Codehaus Foundation. |
| * |
| * 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. |
| */ |
| |
| import org.apache.maven.model.interpolation.reflection.ReflectionValueExtractor; |
| import org.codehaus.plexus.interpolation.AbstractValueSource; |
| |
| /** |
| * Wraps an object, providing reflective access to the object graph of which the |
| * supplied object is the root. Expressions like 'child.name' will translate into |
| * 'rootObject.getChild().getName()' for non-boolean properties, and |
| * 'rootObject.getChild().isName()' for boolean properties. |
| */ |
| public class ObjectBasedValueSource extends AbstractValueSource { |
| |
| private final Object root; |
| |
| /** |
| * Construct a new value source, using the supplied object as the root from |
| * which to start, and using expressions split at the dot ('.') to navigate |
| * the object graph beneath this root. |
| * @param root the root of the graph. |
| */ |
| public ObjectBasedValueSource(Object root) { |
| super(true); |
| this.root = root; |
| } |
| |
| /** |
| * <p>Split the expression into parts, tokenized on the dot ('.') character. Then, |
| * starting at the root object contained in this value source, apply each part |
| * to the object graph below this root, using either 'getXXX()' or 'isXXX()' |
| * accessor types to resolve the value for each successive expression part. |
| * Finally, return the result of the last expression part's resolution.</p> |
| * |
| * <p><b>NOTE:</b> The object-graph nagivation actually takes place via the |
| * {@link ReflectionValueExtractor} class.</p> |
| */ |
| public Object getValue(String expression) { |
| if (expression == null || expression.trim().isEmpty()) { |
| return null; |
| } |
| |
| try { |
| return ReflectionValueExtractor.evaluate(expression, root, false); |
| } catch (Exception e) { |
| addFeedback("Failed to extract \'" + expression + "\' from: " + root, e); |
| } |
| |
| return null; |
| } |
| } |