mongodb系列之四：java高级查询

转载自：http://blog.csdn.net/maosijunzi/article/details/42100535

直接上代码（依赖代码请查看之前的博客）：

 public void query() {
         // $or (查询id等于1或者id等于2的数据)
         BasicDBObject queryObject = new BasicDBObject().append(
                 QueryOperators.OR,
                 new BasicDBObject[] { new BasicDBObject("id", 1),
                         new BasicDBObject("id", 2) });
         find(queryObject, "(查询id等于1或者id等于2的数据)");

         // $and(查询id等于10并且name等于10的数据)
         queryObject = new BasicDBObject().append(QueryOperators.AND,
                 new BasicDBObject[] { new BasicDBObject("id", 10),
                         new BasicDBObject("name", "10") });
         find(queryObject, "(查询id等于10并且name等于10的数据)");

         // $gt（查询id大于10的数据）
         queryObject = new BasicDBObject().append("id",
                 new BasicDBObject().append(QueryOperators.GT, 10));
         find(queryObject, "（查询id大于10的数据）");
         // $gte （查询id大于等于10的数据）
         queryObject = new BasicDBObject().append("id",
                 new BasicDBObject().append(QueryOperators.GTE, 11));
         find(queryObject, "（查询id大于等于11的数据）");
         // $lt
         queryObject = new BasicDBObject().append("id",
                 new BasicDBObject().append(QueryOperators.LT, 2));
         find(queryObject, "（查询id小于2的数据）");
         // $lte
         queryObject = new BasicDBObject().append("id",
                 new BasicDBObject().append(QueryOperators.LTE, 2));
         find(queryObject, "（查询id小于等于2的数据）");

         // $in
         queryObject = new BasicDBObject().append("id", new BasicDBObject(
                 QueryOperators.IN, new int[] { 1, 2 }));
         find(queryObject, "（查询id为1和2的数据）");
         // $nin
         queryObject = new BasicDBObject().append("id", new BasicDBObject(
                 QueryOperators.NIN, new int[] { 1, 2, 3, 4, 5, 6, 7, 8, 9 }));
         find(queryObject, "（查询id不为1,2,3,4,5,6,7,8,9的数据）");

         // 还有很多其他的高级查询方式可以参见QueryOperators类
     }

     public void find(BasicDBObject condition, String str) {
         System.out.println("================" + str + "==================");
         DB db = MongoManager.getDB(Constants.DB);
         DBCollection collection = db.getCollection(Constants.COLLECTION_USER);
         DBCursor find = collection.find(condition);
         while (find.hasNext()) {
             User user = new User();
             user.parse(find.next());
             System.out.println(user);
         }

     }

     public static void main(String[] args) {
         UserDao userDao = new UserDao();
         userDao.query();
     }

QueryOperators类源码：

 // QueryOperators.java

 /**
  *      Copyright (C) 2010 10gen Inc.
  *
  *   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.
  */
 package com.mongodb;

 /**
  * MongoDB keywords for various query operations
  *
  * @author Julson Lim
  */
 public class QueryOperators {
     public static final String OR = "$or";
     public static final String AND = "$and";

     public static final String GT = "$gt";
     public static final String GTE = "$gte";
     public static final String LT = "$lt";
     public static final String LTE = "$lte";

     public static final String NE = "$ne";
     public static final String IN = "$in";
     public static final String NIN = "$nin";
     public static final String MOD = "$mod";
     public static final String ALL = "$all";
     public static final String SIZE = "$size";
     public static final String EXISTS = "$exists";
     public static final String ELEM_MATCH = "$elemMatch";

     // (to be implemented in QueryBuilder)
     public static final String WHERE = "$where";
     public static final String NOR = "$nor";
     public static final String TYPE = "$type";
     public static final String NOT = "$not";

     // geo operators
     public static final String WITHIN = "$within";
     public static final String NEAR = "$near";
     public static final String NEAR_SPHERE = "$nearSphere";
     public static final String BOX = "$box";
     public static final String CENTER = "$center";
     public static final String POLYGON = "$polygon";
     public static final String CENTER_SPHERE = "$centerSphere";
     // (to be implemented in QueryBuilder)
     public static final String MAX_DISTANCE = "$maxDistance";
     public static final String UNIQUE_DOCS = "$uniqueDocs";


     // meta query operators (to be implemented in QueryBuilder)
     public static final String RETURN_KEY = "$returnKey";
     public static final String MAX_SCAN = "$maxScan";
     public static final String ORDER_BY = "$orderby";
     public static final String EXPLAIN =  "$explain";
     public static final String SNAPSHOT = "$snapshot";
     public static final String MIN = "$min";
     public static final String MAX = "$max";
     public static final String SHOW_DISK_LOC = "$showDiskLoc";
     public static final String HINT = "$hint";
     public static final String COMMENT = "$comment";
 }

 

输出结果：

 ================(查询id等于1或者id等于2的数据)==================
 id:1,name:jinhui,address:beijing
 id:2,name:manman,address:beijing
 ================(查询id等于10并且name等于10的数据)==================
 ================（查询id大于10的数据）==================
 id:11,name:11,address:11
 id:12,name:12,address:12
 ================（查询id大于等于11的数据）==================
 id:11,name:11,address:11
 id:12,name:12,address:12
 ================（查询id小于2的数据）==================
 id:1,name:jinhui,address:beijing
 ================（查询id小于等于2的数据）==================
 id:1,name:jinhui,address:beijing
 id:2,name:manman,address:beijing
 ================（查询id为1和2的数据）==================
 id:1,name:jinhui,address:beijing
 id:2,name:manman,address:beijing
 ================（查询id不为1,2,3,4,5,6,7,8,9的数据）==================
 id:11,name:11,address:11
 id:12,name:12,address:12

数据库数据如下所示：