Java tutorial
/***************************************************************** * 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.cayenne.exp.parser; import java.io.IOException; import java.util.List; import org.apache.cayenne.CayenneRuntimeException; import org.apache.cayenne.DataObject; import org.apache.cayenne.exp.Expression; import org.apache.cayenne.map.Entity; import org.apache.cayenne.map.ObjEntity; import org.apache.cayenne.reflect.PropertyUtils; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; public class ASTObjPath extends ASTPath { private static final long serialVersionUID = -3574281576491705706L; private static final Log LOGGER = LogFactory.getLog(ASTObjPath.class); public static final String OBJ_PREFIX = "obj:"; /** * Constructor used by expression parser. Do not invoke directly. */ ASTObjPath(int id) { super(id); } public ASTObjPath() { super(ExpressionParserTreeConstants.JJTOBJPATH); } public ASTObjPath(Object value) { super(ExpressionParserTreeConstants.JJTOBJPATH); setPath(value); } @Override protected Object evaluateNode(Object o) throws Exception { return (o instanceof DataObject) ? ((DataObject) o).readNestedProperty(path) : (o instanceof Entity) ? evaluateEntityNode((Entity) o) : PropertyUtils.getProperty(o, path); } /** * Creates a copy of this expression node, without copying children. */ @Override public Expression shallowCopy() { ASTObjPath copy = new ASTObjPath(id); copy.path = path; return copy; } /** * @since 4.0 */ @Override public void appendAsEJBQL(List<Object> parameterAccumulator, Appendable out, String rootId) throws IOException { out.append(rootId); out.append('.'); out.append(path); } /** * @since 4.0 */ @Override public void appendAsString(Appendable out) throws IOException { out.append(path); } @Override public int getType() { return Expression.OBJ_PATH; } void injectValue(Object source, Object value) { if (getPath().indexOf(ObjEntity.PATH_SEPARATOR) == -1) { try { if (source instanceof DataObject) { ((DataObject) source).writeProperty(getPath(), value); } else { PropertyUtils.setProperty(source, getPath(), value); } } catch (CayenneRuntimeException ex) { LOGGER.warn("Failed to inject value " + value + " on path " + getPath() + " to " + source, ex); } } } }