Java tutorial
/** * Licensed to the Rhiot under one or more * contributor license agreements. See the NOTICE file distributed with * this work for additional information regarding copyright ownership. * The 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 com.github.camellabs.iot.cloudlet.document.driver.mongodb; import com.mongodb.BasicDBObject; import com.mongodb.DBObject; import java.util.Collections; import java.util.List; import java.util.Map; import static io.rhiot.utils.Maps.immutableMapOf; import static java.lang.Boolean.parseBoolean; import static java.util.stream.Collectors.toList; public class MongoQueryBuilder { private static final Map<String, String> SIMPLE_SUFFIX_OPERATORS = immutableMapOf("GreaterThan", "$gt", "GreaterThanEqual", "$gte", "LessThan", "$lt", "LessThanEqual", "$lte", "NotIn", "$nin", "In", "$in"); public DBObject jsonToMongoQuery(DBObject jsonQuery) { BasicDBObject mongoQuery = new BasicDBObject(); for (String originalKey : jsonQuery.keySet()) { String compoundKey = originalKey.replaceAll("(.)_", "$1."); String suffixOperator = findFirstMatchOperator(originalKey); if (suffixOperator != null) { addRestriction(mongoQuery, compoundKey, suffixOperator, SIMPLE_SUFFIX_OPERATORS.get(suffixOperator), jsonQuery.get(originalKey)); continue; } if (originalKey.endsWith("Contains")) { addRestriction(mongoQuery, compoundKey, "Contains", "$regex", ".*" + jsonQuery.get(originalKey) + ".*"); } else { mongoQuery.put(compoundKey, new BasicDBObject("$eq", jsonQuery.get(originalKey))); } } return mongoQuery; } // TODO Don't return stack traces public DBObject queryBuilderToSortConditions(Map<String, Object> queryBuilder) { int order = parseBoolean(queryBuilder.getOrDefault("sortAscending", true).toString()) ? 1 : -1; List<String> orderBy = (List<String>) queryBuilder.getOrDefault("orderBy", Collections.emptyList()); // Suggest that it should list here if (orderBy.size() == 0) { return new BasicDBObject("$natural", order); } else { BasicDBObject sort = new BasicDBObject(); for (String by : orderBy) { sort.put(by, order); } return sort; } } // Helpers private String findFirstMatchOperator(String originalKey) { List<String> matchingSuffixOperators = SIMPLE_SUFFIX_OPERATORS.keySet().parallelStream() .filter(originalKey::endsWith).collect(toList()); return matchingSuffixOperators.isEmpty() ? null : matchingSuffixOperators.get(0); } private void addRestriction(BasicDBObject query, String propertyWithOperator, String propertyOperator, String operator, Object value) { String property = propertyWithOperator.replaceAll(propertyOperator + "$", ""); if (query.containsField(property)) { BasicDBObject existingRestriction = (BasicDBObject) query.get(property); existingRestriction.put(operator, value); } else { query.put(property, new BasicDBObject(operator, value)); } } }