| /** |
| * 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.gora.mongodb.store; |
| |
| import java.io.FileInputStream; |
| import java.io.IOException; |
| import java.io.InputStream; |
| import java.util.List; |
| |
| import org.apache.gora.persistency.impl.PersistentBase; |
| import org.jdom.Document; |
| import org.jdom.Element; |
| import org.jdom.input.SAXBuilder; |
| |
| /** |
| * A builder for creating the mapper. This will allow building a thread safe |
| * {@link org.apache.gora.mongodb.store.MongoMapping} using simple immutabilty. |
| */ |
| public class MongoMappingBuilder<K, T extends PersistentBase> { |
| |
| // Document description |
| static final String TAG_DOCUMENT = "document"; |
| |
| static final String ATT_COLLECTION = "collection"; |
| |
| static final String STAG_DOCUMENT_FIELD = "field"; |
| |
| static final String ATT_NAME = "name"; |
| |
| static final String ATT_TYPE = "type"; |
| |
| static final String STAG_SUBDOCUMENT = "subdocument"; |
| |
| // Class description |
| static final String TAG_CLASS = "class"; |
| |
| static final String ATT_KEYCLASS = "keyClass"; |
| |
| static final String ATT_DOCUMENT = "document"; |
| |
| static final String TAG_FIELD = "field"; |
| |
| static final String ATT_FIELD = "docfield"; |
| |
| private final MongoStore<K, T> dataStore; |
| |
| /** |
| * Mapping instance being built |
| */ |
| private MongoMapping mapping; |
| |
| public MongoMappingBuilder(final MongoStore<K, T> store) { |
| this.dataStore = store; |
| this.mapping = new MongoMapping(); |
| } |
| |
| /** |
| * Return the built mapping if it is in a legal state |
| */ |
| public MongoMapping build() { |
| if (mapping.getCollectionName() == null) |
| throw new IllegalStateException("A collection is not specified"); |
| return mapping; |
| } |
| |
| /** |
| * Load the {@link org.apache.gora.mongodb.store.MongoMapping} from an input stream |
| * passed in parameter. |
| * |
| * @param is |
| * input stream holding the mapping |
| * @throws java.io.IOException |
| */ |
| protected void fromInputStream(InputStream is) throws IOException { |
| try { |
| SAXBuilder saxBuilder = new SAXBuilder(); |
| if (is == null) { |
| throw new IllegalArgumentException("The mapping input stream is null!"); |
| } |
| Document doc = saxBuilder.build(is); |
| Element root = doc.getRootElement(); |
| // No need to use documents descriptions for now... |
| // Extract class descriptions |
| @SuppressWarnings("unchecked") |
| List<Element> classElements = root.getChildren(TAG_CLASS); |
| for (Element classElement : classElements) { |
| final Class<T> persistentClass = dataStore.getPersistentClass(); |
| final Class<K> keyClass = dataStore.getKeyClass(); |
| if (haveKeyClass(keyClass, classElement) |
| && havePersistentClass(persistentClass, classElement)) { |
| loadPersistentClass(classElement, persistentClass); |
| break; // only need that |
| } |
| } |
| } catch (IOException ex) { |
| MongoStore.LOG.error(ex.getMessage()); |
| MongoStore.LOG.error(ex.getStackTrace().toString()); |
| throw ex; |
| } catch (Exception ex) { |
| MongoStore.LOG.error(ex.getMessage()); |
| MongoStore.LOG.error(ex.getStackTrace().toString()); |
| throw new IOException(ex); |
| } |
| } |
| |
| private boolean havePersistentClass(final Class<T> persistentClass, |
| final Element classElement) { |
| return classElement.getAttributeValue(ATT_NAME).equals( |
| persistentClass.getName()); |
| } |
| |
| private boolean haveKeyClass(final Class<K> keyClass, |
| final Element classElement) { |
| return classElement.getAttributeValue(ATT_KEYCLASS).equals( |
| keyClass.getName()); |
| } |
| |
| /** |
| * Handle the XML parsing of the class definition. |
| * |
| * @param classElement |
| * the XML node containing the class definition |
| */ |
| protected void loadPersistentClass(Element classElement, |
| Class<T> pPersistentClass) { |
| |
| String docNameFromMapping = classElement.getAttributeValue(ATT_DOCUMENT); |
| String collName = dataStore.getSchemaName(docNameFromMapping, |
| pPersistentClass); |
| |
| mapping.setCollectionName(collName); |
| // docNameFromMapping could be null here |
| if (!collName.equals(docNameFromMapping)) { |
| MongoStore.LOG |
| .info("Keyclass and nameclass match but mismatching table names " |
| + " mappingfile schema is '" + docNameFromMapping |
| + "' vs actual schema '" + collName |
| + "' , assuming they are the same."); |
| if (docNameFromMapping != null) { |
| mapping.renameCollection(docNameFromMapping, collName); |
| } |
| } |
| |
| // Process fields declaration |
| @SuppressWarnings("unchecked") |
| List<Element> fields = classElement.getChildren(TAG_FIELD); |
| for (Element field : fields) { |
| mapping |
| .addClassField(field.getAttributeValue(ATT_NAME), |
| field.getAttributeValue(ATT_FIELD), |
| field.getAttributeValue(ATT_TYPE)); |
| } |
| } |
| |
| } |