001    /*
002     * Licensed to the Apache Software Foundation (ASF) under one or more
003     * contributor license agreements.  See the NOTICE file distributed with
004     * this work for additional information regarding copyright ownership.
005     * The ASF licenses this file to You under the Apache License, Version 2.0
006     * (the "License"); you may not use this file except in compliance with
007     * the License.  You may obtain a copy of the License at
008     *
009     *     http://www.apache.org/licenses/LICENSE-2.0
010     *
011     * Unless required by applicable law or agreed to in writing, software
012     * distributed under the License is distributed on an "AS IS" BASIS,
013     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014     * See the License for the specific language governing permissions and
015     * limitations under the License.
016     */
017    package org.apache.commons.jxpath.ri.model;
018    
019    import java.util.Locale;
020    
021    import org.apache.commons.jxpath.JXPathContext;
022    import org.apache.commons.jxpath.Variables;
023    import org.apache.commons.jxpath.ri.QName;
024    
025    /**
026     * NodePointerFactory to create {@link VariablePointer VariablePointers}.
027     * @author Matt Benson
028     * @since JXPath 1.3
029     * @version $Revision: 652845 $ $Date: 2008-05-02 12:46:46 -0500 (Fri, 02 May 2008) $
030     */
031    public class VariablePointerFactory implements NodePointerFactory {
032        /** factory order constant */
033        public static final int VARIABLE_POINTER_FACTORY_ORDER = 890;
034    
035        /**
036         * Node value wrapper to trigger a VariablePointerFactory.
037         */
038        public static final class VariableContextWrapper {
039            private final JXPathContext context;
040    
041            /**
042             * Create a new VariableContextWrapper.
043             * @param context to wrap
044             */
045            private VariableContextWrapper(JXPathContext context) {
046                this.context = context;
047            }
048    
049            /**
050             * Get the original (unwrapped) context.
051             *
052             * @return JXPathContext.
053             */
054            public JXPathContext getContext() {
055                return context;
056            }
057        }
058    
059        /**
060         * VariableContextWrapper factory method.
061         * @param context the JXPathContext to wrap.
062         * @return VariableContextWrapper.
063         */
064        public static VariableContextWrapper contextWrapper(JXPathContext context) {
065            return new VariableContextWrapper(context);
066        }
067    
068        public NodePointer createNodePointer(QName name, Object object,
069                Locale locale) {
070            if (object instanceof VariableContextWrapper) {
071                JXPathContext varCtx = ((VariableContextWrapper) object).getContext();
072                while (varCtx != null) {
073                    Variables vars = varCtx.getVariables();
074                    if (vars.isDeclaredVariable(name.toString())) {
075                        return new VariablePointer(vars, name);
076                    }
077                    varCtx = varCtx.getParentContext();
078                }
079                // The variable is not declared, but we will create
080                // a pointer anyway in case the user wants to set, rather
081                // than get, the value of the variable.
082                return new VariablePointer(name);
083            }
084            return null;
085        }
086    
087        public NodePointer createNodePointer(NodePointer parent, QName name,
088                Object object) {
089            return createNodePointer(name, object, null);
090        }
091    
092        public int getOrder() {
093            return VARIABLE_POINTER_FACTORY_ORDER;
094        }
095    
096    }