1 package MongoDB; 2  3 import com.mongodb.BasicDBObject; 4 import com.mongodb.DB; 5 import com.mongodb.DBCollection; 6 import com.mongodb.DBCursor; 7 import com.mongodb.DBObject; 8 import com.mongodb.Mongo; 9 import java.net.UnknownHostException;10 import java.util.Set;11 12 import org.junit.Test;13 14 public class TestMongoDBDriver {15 16     @Test17     public void testCRUD() throws UnknownHostException {18         // 连接到mongodb19         Mongo mongo = new Mongo("localhost", 27017);20 21         // 打开数据库test22         DB db = mongo.getDB("test");23 24         // 遍历所有集合的名字25         Set<String> colls = db.getCollectionNames();26         for (String s : colls) {27             System.out.println(s);28             // 先删除所有Collection(类似于关系数据库中的"表")29             if (!s.equals("system.indexes")) {30                 db.getCollection(s).drop();31             }32         }33 34         // 取得集合emp(若：emp不存在，mongodb将自动创建该集合)35         DBCollection coll = db.getCollection("emp");36 37         // delete all38         DBCursor dbCursor = coll.find();39         for (DBObject dbObject : dbCursor) {40             coll.remove(dbObject);41         }42 43         // create44         BasicDBObject doc = new BasicDBObject("name", "杨俊明").append("sex", "男")45                 .append("address",46                         new BasicDBObject("postcode", "201202").append(47                                 "street", "田林路888号").append("city", "上海"));48         coll.insert(doc);49 50         // retrieve51         BasicDBObject docFind = new BasicDBObject("name", "杨俊明");52         DBObject findResult = coll.findOne(docFind);53         System.out.println(findResult);54 55         // update56         doc.put("sex", "MALE");// 把sex属性从"男"，改成"MALE"57         coll.update(docFind, doc);58         findResult = coll.findOne(docFind);59         System.out.println(findResult);60 61         coll.dropIndexes();// 先删除所有索引62         // create index63         coll.createIndex(new BasicDBObject("name", 1)); // 1代表升序64     }65 66 }