MongoDB之Java测试代码（DAO层）
dao
java
mongodb
程式碼
測試
MongoInit.java是数据库初始化及连接类 MongoUtils.java是对mongodb的各种操作方法 MongoInit.java package com.wlwcloud.datatest;import java.io.File;import java.io.FileInputStream;import java.io.IOException;import java.net.UnknownHostException;i
MongoInit.java是数据库初始化及连接类
MongoUtils.java是对mongodb的各种操作方法
MongoInit.java
package com.wlwcloud.datatest;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.net.UnknownHostException;
import java.util.Properties;
import org.apache.log4j.Logger;
import com.mongodb.DB;
import com.mongodb.DBCollection;
import com.mongodb.Mongo;
import com.mongodb.MongoOptions;
import com.mongodb.ServerAddress;
/**
* Mongo工具类:设计为单例模式，每当月份发生变化，数据库连接名称就会发生变化，这是业务规则 因MongoDB的Java驱动是线程安全的，对于一般的应用，只要一个Mongo实例即可，Mongo有个内置的连接池（池大小默认为10个）。
* 对于有大量写和读的环境中，为了确保在一个Session中使用同一个DB时，我们可以用以下方式保证一致性： DB mdb =mongo.getDB('dbname'); mdb.requestStart(); // 业务代码 mdb.requestDone();
* DB和DBCollection是绝对线程安全的
* @author undoner
*/
public class MongoInit {
/** DB监听端口号 */
private static int DBPort = 27017;
/** DB连接URL */
private static String DBUrl = "localhost";
/** 连接DB库名称 */
private static String DBName = "wlwdb";
static Logger log = Logger.getRootLogger();
private static Mongo mongo;
private static DBCollection coll;
private static DB db;
static {
try {
DBproperties();
MongoOptions options = new MongoOptions();
options.autoConnectRetry = true;
options.connectionsPerHost = 1000;
options.maxWaitTime = 5000;
options.socketTimeout = 0;
options.connectTimeout = 15000;
options.threadsAllowedToBlockForConnectionMultiplier = 5000;
// 事实上，Mongo实例代表了一个数据库连接池，即使在多线程的环境中，一个Mongo实例对我们来说已经足够了
ServerAddress serverAddress = new ServerAddress(DBUrl, DBPort);
mongo = new Mongo(serverAddress, options);
} catch (UnknownHostException e) {
log.info("get mongo instance failed");
}
}
static void DBproperties() {
// 读取配置文件config.properties中的属性值
String myFilePath = MongoInit.class.getResource("/").getPath() + "MongoDBConfig.properties";
Properties properties = new Properties();
FileInputStream fileInputStream = null;
try {
fileInputStream = new FileInputStream(myFilePath);
properties.load(fileInputStream);
DBPort = Integer.parseInt((String) properties.getProperty("DBPort"));
DBUrl = (String) properties.getProperty("DBUrl");
DBName = (String) properties.getProperty("DBName");
} catch (Exception e) {
e.printStackTrace();
} finally {
try {
fileInputStream.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
public static DB getDB() {
if (db == null) {
db = mongo.getDB(DBName);
}
return db;
}
public static Mongo getMong() {
return mongo;
}
public static DBCollection getColl(String collname) {
return getDB().getCollection(collname);
}
}登入後複製
package com.wlwcloud.datatest;
import java.net.UnknownHostException;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Date;
import java.util.List;
import java.util.Set;
import java.util.regex.Pattern;
import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.ketayao.ketacustom.entity.main.User;
import com.ketayao.utils.SecurityUtils;
import com.mongodb.AggregationOutput;
import com.mongodb.BasicDBList;
import com.mongodb.BasicDBObject;
import com.mongodb.BasicDBObjectBuilder;
import com.mongodb.DB;
import com.mongodb.DBCollection;
import com.mongodb.DBCursor;
import com.mongodb.DBObject;
import com.mongodb.MapReduceCommand;
import com.mongodb.MapReduceOutput;
import com.mongodb.Mongo;
import com.mongodb.MongoException;
import com.mongodb.QueryBuilder;
import com.mongodb.WriteConcern;
public class MongoUtils {
//DBCursor cursor = coll.find(condition).addOption(Bytes.QUERYOPTION_NOTIMEOUT);//设置游标不要超时
/**
* 获取所有数据库实例
*/
public void testGetDBS() {
List<String> dbnames = MongoInit.getMong().getDatabaseNames();
for (String dbname : dbnames) {
System.out.println("dbname:" + dbname);
}
}
/**
* 删除数据库
*/
public void dropDatabase(String dbname) {
MongoInit.getMong().dropDatabase(dbname);
}
/**
* 查询所有表名
*/
public void getAllCollections() {
Set<String> colls = MongoInit.getDB().getCollectionNames();
for (String s : colls) {
System.out.println("Collections:"+s);
}
}
/**
* 删除一个表
*/
public void dropCollection(String collection) {
MongoInit.getColl(collection).drop();
}
/**
* 添加一条记录
*/
public void addData(String dbCollection,String dataID,String dataTime,String dataContent,String dataStatus) {
DBCollection coll = MongoInit.getColl(dbCollection);
BasicDBObject doc = new BasicDBObject();
doc.put("id", dataID);
doc.put("time", dataTime);
doc.put("data", dataContent);
doc.put("status", dataStatus);
coll.insert(doc);
// 设定write concern，以便操作失败时得到提示
coll.setWriteConcern(WriteConcern.SAFE);
findOne(dbCollection);
}
/**
* 创建索引
*/
public void createIndex(String collection) {
MongoInit.getColl(collection).createIndex(new BasicDBObject("index_id", 1));
}
/**
* 获取索引信息
*/
public void getIndexInfo(String dbCollection) {
List<DBObject> list = MongoInit.getColl(dbCollection).getIndexInfo();
for (DBObject o : list) {
System.out.println(o);
}
}
/**
* 添加多条记录
*/
public void addMultiData() {
for (int i = 0; i < 100; i++) {
MongoInit.getColl("wujintao").insert(
new BasicDBObject().append("i", i));
}
List<DBObject> docs = new ArrayList<DBObject>();
for (int i = 0; i < 50; i++) {
docs.add(new BasicDBObject().append("i", i));
}
MongoInit.getColl("wujintao").insert(docs);
// 设定write concern，以便操作失败时得到提示
MongoInit.getColl("wujintao").setWriteConcern(WriteConcern.SAFE);
}
/**
* 查找第一条记录
*/
public void findOne(String dbCollection) {
DBObject myDoc = MongoInit.getColl(dbCollection).findOne();
System.out.println(myDoc);
}
/**
* 获取表中所有记录条数
*/
public void count(String dbCollection) {
System.out.println(MongoInit.getColl(dbCollection).getCount());
System.out.println(MongoInit.getColl(dbCollection).count());
}
/**
* 获取查询结果集的记录数
*/
public void getCount(String dbCollection,String dataID) {
DBObject query = new BasicDBObject("id", dataID);
long count = MongoInit.getColl(dbCollection).count(query);
System.out.println(count);
}
/**
* 查询所有结果
*/
public void getAllDocuments(String dbCollection) {
DBCursor cursor = MongoInit.getColl(dbCollection).find();
try {
while (cursor.hasNext()) {
System.out.println(cursor.next());
}
} finally {
cursor.close();
}
}
/**
* 按照一个条件查询
*/
public void queryByConditionOne() {
BasicDBObject query = new BasicDBObject();
query.put("name", "MongoDB");
DBCursor cursor = MongoInit.getColl("wujintao").find(query);
try {
while (cursor.hasNext()) {
System.out.println(cursor.next());
}
} finally {
cursor.close();
}
}
public List<SensorData> queryById(String id) {
User user = SecurityUtils.getLoginUser();
BasicDBObject query = new BasicDBObject();
System.out.print(id);
query.put("id", id);
String table="table_";
DBCursor cursor = MongoInit.getColl("table_"+user.getUsername()).find(query);
List<DBObject> list=cursor.toArray();
System.out.println(list.size());
System.out.println("dao.."+list.toString());
List<SensorData> sensordata=new ArrayList<SensorData>();
for(int i=1;i<list.size();i++)
{
String sid=(String)list.get(i).get("id");
String stime=(String)list.get(i).get("time");
String sdata=(String)list.get(i).get("data");
String status=(String)list.get(i).get("status");
String sstatus;
if(status.equals("0"))sstatus="正常";
else if(status.equals("1")) sstatus="删除";
else sstatus="未知状态";
SensorData a=new SensorData(sid,stime,sdata,sstatus);
//System.out.print(a.getData()+a.getId()+a.getStatus()+a.getTime());
sensordata.add(a);
}
return sensordata;
/* try {
while (cursor.hasNext()) {
System.out.println(cursor.next());
}
} finally {
cursor.close();
} */
}
/**
* AND多条件查询,区间查询
*/
public void queryMulti() {
BasicDBObject query = new BasicDBObject();
// 查询j不等于3,k大于10的结果集
query.put("j", new BasicDBObject("$ne", 3));
query.put("k", new BasicDBObject("$gt", 10));
DBCursor cursor = MongoInit.getColl("wujintao").find(query);
try {
while (cursor.hasNext()) {
System.out.println(cursor.next());
}
} finally {
cursor.close();
}
}
/**
* 区间查询
* select * from table where i >50
*/
public void queryMulti2() {
BasicDBObject query = new BasicDBObject();
query = new BasicDBObject();
query.put("i", new BasicDBObject("$gt", 50)); // e.g. find all where i >
DBCursor cursor = MongoInit.getColl("wujintao").find(query);
try {
while (cursor.hasNext()) {
System.out.println(cursor.next());
}
} finally {
cursor.close();
}
}
/**
* 区间查询
* select * from table where 20 < i <= 30
//比较符
//"$gt"： 大于
//"$gte"：大于等于
//"$lt"： 小于
//"$lte"：小于等于
//"$in"： 包含
*/
public void queryMulti3() {
BasicDBObject query = new BasicDBObject();
query = new BasicDBObject();
query.put("i", new BasicDBObject("$gt", 20).append("$lte", 30));
DBCursor cursor = MongoInit.getColl("wujintao").find(query);
try {
while (cursor.hasNext()) {
System.out.println(cursor.next());
}
} finally {
cursor.close();
}
}
/**
* 组合in和and select * from test_Table where (a=5 or b=6) and (c=5 or d = 6)
*/
public void queryMulti4() {
BasicDBObject query11 = new BasicDBObject();
query11.put("a", 1);
BasicDBObject query12 = new BasicDBObject();
query12.put("b", 2);
List<BasicDBObject> orQueryList1 = new ArrayList<BasicDBObject>();
orQueryList1.add(query11);
orQueryList1.add(query12);
BasicDBObject orQuery1 = new BasicDBObject("$or", orQueryList1);
BasicDBObject query21 = new BasicDBObject();
query21.put("c", 5);
BasicDBObject query22 = new BasicDBObject();
query22.put("d", 6);
List<BasicDBObject> orQueryList2 = new ArrayList<BasicDBObject>();
orQueryList2.add(query21);
orQueryList2.add(query22);
BasicDBObject orQuery2 = new BasicDBObject("$or", orQueryList2);
List<BasicDBObject> orQueryCombinationList = new ArrayList<BasicDBObject>();
orQueryCombinationList.add(orQuery1);
orQueryCombinationList.add(orQuery2);
BasicDBObject finalQuery = new BasicDBObject("$and",
orQueryCombinationList);
DBCursor cursor = MongoInit.getColl("wujintao").find(finalQuery);
}
/**
* IN查询
* if i need to query name in (a,b); just use { name : { $in : ['a', 'b'] } }
* select * from things where name='a' or name='b'
* @param coll
*/
public void queryIn() {
BasicDBList values = new BasicDBList();
values.add("a");
values.add("b");
BasicDBObject in = new BasicDBObject("$in", values);
DBCursor cursor = MongoInit.getColl("wujintao").find(
new BasicDBObject("name", in));
try {
while (cursor.hasNext()) {
System.out.println(cursor.next());
}
} finally {
cursor.close();
}
}
/**
* 或查询
* select * from table where name = '12' or title = 'p'
* @param coll
*/
public void queryOr() {
QueryBuilder query = new QueryBuilder();
query.or(new BasicDBObject("name", 12), new BasicDBObject("title", "p"));
DBCursor cursor = MongoInit.getColl("wujintao").find(query.get()).addSpecial("$returnKey", "");
try {
while (cursor.hasNext()) {
System.out.println(cursor.next());
}
} finally {
cursor.close();
}
}
public void customQueryField() throws UnknownHostException{
Mongo mongo = new Mongo("localhost", 27017);
DB db = mongo.getDB("zhongsou_ad");
BasicDBObjectBuilder bulder = new BasicDBObjectBuilder();
bulder.add("times",1);
bulder.add("aid",1);
DBCursor cusor = db.getCollection("ad_union_ad_c_1").find(new BasicDBObject(),bulder.get());
for (DBObject dbObject : cusor) {
System.out.println(dbObject);
}
}
public void mapReduce() throws UnknownHostException{
Mongo mongo = new Mongo("localhost", 27017);
DB db = mongo.getDB("zhongsou_ad");
/***
* book1 = {name : "Understanding JAVA", pages : 100}
* book2 = {name : "Understanding JSON", pages : 200}
* db.books.save(book1)
* db.books.save(book2)
* book = {name : "Understanding XML", pages : 300}
* db.books.save(book)
* book = {name : "Understanding Web Services", pages : 400}
* db.books.save(book)
* book = {name : "Understanding Axis2", pages : 150}
* db.books.save(book)
*
var map = function() {
var category;
if ( this.pages >= 250 )
category = 'Big Books';
else
category = "Small Books";
emit(category, {name: this.name});
};
var reduce = function(key, values) {
var sum = 0;
values.forEach(function(doc) {
sum += 1;
});
return {books: sum};
};
var count = db.books.mapReduce(map, reduce, {out: "book_results"});
*/
try {
DBCollection books = db.getCollection("books");
BasicDBObject book = new BasicDBObject();
book.put("name", "Understanding JAVA");
book.put("pages", 100);
books.insert(book);
book = new BasicDBObject();
book.put("name", "Understanding JSON");
book.put("pages", 200);
books.insert(book);
book = new BasicDBObject();
book.put("name", "Understanding XML");
book.put("pages", 300);
books.insert(book);
book = new BasicDBObject();
book.put("name", "Understanding Web Services");
book.put("pages", 400);
books.insert(book);
book = new BasicDBObject();
book.put("name", "Understanding Axis2");
book.put("pages", 150);
books.insert(book);
String map = "function() { "+
"var category; " +
"if ( this.pages >= 250 ) "+
"category = 'Big Books'; " +
"else " +
"category = 'Small Books'; "+
"emit(category, {name: this.name});}";
String reduce = "function(key, values) { " +
"var sum = 0; " +
"values.forEach(function(doc) { " +
"sum += 1; "+
"}); " +
"return {books: sum};} ";
MapReduceCommand cmd = new MapReduceCommand(books, map, reduce,
null, MapReduceCommand.OutputType.INLINE, null);
MapReduceOutput out = books.mapReduce(cmd);
for (DBObject o : out.results()) {
System.out.println(o.toString());
}
} catch (Exception e) {
e.printStackTrace();
}
}
public void GroupByManyField() throws UnknownHostException{
//此方法没有运行成功
Mongo mongo = new Mongo("localhost", 27017);
DB db = mongo.getDB("libary");
DBCollection books = db.getCollection("books");
BasicDBObject groupKeys = new BasicDBObject();
groupKeys.put("total", new BasicDBObject("$sum","pages"));
BasicDBObject condition = new BasicDBObject();
condition.append("pages", new BasicDBObject().put("$gt", 0));
String reduce = "function(key, values) { " +
"var sum = 0; " +
"values.forEach(function(doc) { " +
"sum += 1; "+
"}); " +
"return {books: sum};} ";
/**
BasicDBList basicDBList = (BasicDBList)db.getCollection("mongodb中集合编码或者编码")
.group(DBObject key, --分组字段，即group by的字段
DBObject cond, --查询中where条件
DBObject initial, --初始化各字段的值
String reduce, --每个分组都需要执行的Function
String finial --终结Funciton对结果进行最终的处理
*/
DBObject obj = books.group(groupKeys, condition, new BasicDBObject(), reduce);
System.out.println(obj);
AggregationOutput ouput = books.aggregate(new BasicDBObject("$group",groupKeys));
System.out.println(ouput.getCommandResult());
System.out.println(books.find(new BasicDBObject("$group",groupKeys)));
}
/**
* 分页查询
*/
public void pageQuery() {
DBCursor cursor = MongoInit.getColl("wujintao").find().skip(0)
.limit(10);
while (cursor.hasNext()) {
System.out.println(cursor.next());
}
}
/**
* 模糊查询
*/
public void likeQuery() {
Pattern john = Pattern.compile("joh?n");
BasicDBObject query = new BasicDBObject("name", john);
// finds all people with "name" matching /joh?n/i
DBCursor cursor = MongoInit.getColl("wujintao").find(query);
}
/**
* 条件删除
*/
public void delete(String dbCollection,String dataID) {
BasicDBObject query = new BasicDBObject();
query.put("id", dataID);
// 找到并且删除，并返回删除的对象
DBObject removeObj = MongoInit.getColl(dbCollection).findAndRemove(query);
System.out.println(removeObj);
}
/**
* 更新
*/
public void update() {
BasicDBObject query = new BasicDBObject();
query.put("name", "liu");
DBObject stuFound = MongoInit.getColl("wujintao").findOne(query);
stuFound.put("name", stuFound.get("name") + "update_1");
MongoInit.getColl("wujintao").update(query, stuFound);
}
public void testGpsData() {
try {
//13862082455:117.13172:029.77659:131.2580
Date d = new Date();
SimpleDateFormat sdf =new SimpleDateFormat("yyyy-MM-dd HH:mm:ss SSS");
String dateNowStr = sdf.format(d);
System.out.println(dateNowStr);
DBCollection coll = MongoInit.getColl("table_admin");
BasicDBObject doc = new BasicDBObject();
doc.put("id", "12345678");
doc.put("time", dateNowStr);
doc.put("data", "117.13172:029.77659:131.2580");
doc.put("status", "0");
coll.insert(doc);
// 设定write concern，以便操作失败时得到提示
coll.setWriteConcern(WriteConcern.SAFE);
BasicDBObject dsort = new BasicDBObject();
dsort.put("time", -1);
BasicDBObject searchDevice = new BasicDBObject();
searchDevice.put("id", "12345678");
DBCursor cursor = coll.find(searchDevice).sort(dsort);
List<DBObject> list = cursor.toArray();
//ArrayList<SensorData> listSensorData=new ArrayList<SensorData>(list.size());
ObjectMapper mapper = new ObjectMapper();
String jsonfromList = null;
try {
//list转json
jsonfromList = mapper.writeValueAsString(list);
} catch (JsonProcessingException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
//System.out.println(jsonfromList);
// for(int i=0;i<list.size();i++)
// {
// System.out.println((String) list.get(i).get("time"));
//}
//System.out.println(list.size()+","+listSensorData);//list的长度
// System.out.println(cursor.count());//计算结果的数量，类似于(mysql count()函数),不受limit的影响
// while (cursor.hasNext()) {
// System.out.println(cursor.next());
// }
System.out.println("The Search Query has Executed!");
} catch (MongoException e) {
e.printStackTrace();
}
}
public static void main(String[] args) {
String dbname="wlwdb";
String dbCollection="table_admin";
String dbCollection1="15257102317";
String dataID="12345678";
MongoUtils tb=new MongoUtils();
tb.testGetDBS();//查询所有数据库
tb.getAllCollections();//查询所有表
//
// tb.findOne(dbCollection);//查找第一条记录
tb.testGpsData();
tb.getAllDocuments(dbCollection);//获取制定表明的所有数据
//tb.dropDatabase(dbname);//删除指定数据库
//tb.delete(dbCollection,dataID);//删除制定表明和设备ID的数据
//tb.dropCollection(dbCollection);// 删除一个表
//tb.createIndex(dbCollection1);//创建索引
//tb.getIndexInfo(dbCollection1);//获得表中所有索引
}
}登入後複製
#端口设置 DBPort=27017 #URL DBUrl=localhost #URL DBName=wlwdb
登入後複製
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PHPhassignificantlyimpactedwebdevelopmentandextendsbeyondit.1)ItpowersmajorplatformslikeWordPressandexcelsindatabaseinteractions.2)PHP'sadaptabilityallowsittoscaleforlargeapplicationsusingframeworkslikeLaravel.3)Beyondweb,PHPisusedincommand-linescrip
PHP與Python：用例和應用程序
Apr 17, 2025 am 12:23 AM
PHP適用於Web開發和內容管理系統，Python適合數據科學、機器學習和自動化腳本。 1.PHP在構建快速、可擴展的網站和應用程序方面表現出色，常用於WordPress等CMS。 2.Python在數據科學和機器學習領域表現卓越，擁有豐富的庫如NumPy和TensorFlow。
MongoDB vs. Oracle：為您的需求選擇正確的數據庫
Apr 22, 2025 am 12:10 AM
MongoDB適合非結構化數據和高擴展性需求，Oracle適合需要嚴格數據一致性的場景。 1.MongoDB靈活存儲不同結構數據，適合社交媒體和物聯網。 2.Oracle結構化數據模型確保數據完整性，適用於金融交易。 3.MongoDB通過分片橫向擴展，Oracle通過RAC縱向擴展。 4.MongoDB維護成本低，Oracle維護成本高但支持完善。
作曲家：通過AI的幫助開發PHP
Apr 29, 2025 am 12:27 AM
AI可以幫助優化Composer的使用，具體方法包括：1.依賴管理優化：AI分析依賴關係，建議最佳版本組合，減少衝突。 2.自動化代碼生成：AI生成符合最佳實踐的composer.json文件。 3.代碼質量提升：AI檢測潛在問題，提供優化建議，提高代碼質量。這些方法通過機器學習和自然語言處理技術實現，幫助開發者提高效率和代碼質量。
MongoDB與Oracle：了解關鍵差異
Apr 16, 2025 am 12:01 AM
MongoDB适合处理大规模非结构化数据，Oracle适用于需要事务一致性的企业级应用。1.MongoDB提供灵活性和高性能，适合处理用户行为数据。2.Oracle以稳定性和强大功能著称，适用于金融系统。3.MongoDB使用文档模型，Oracle使用关系模型。4.MongoDB适合社交媒体应用，Oracle适合企业级应用。
在Java的背景下，'平台獨立性”意味著什麼？
Apr 23, 2025 am 12:05 AM
Java的平台獨立性是指編寫的代碼可以在任何安裝了JVM的平台上運行，無需修改。 1)Java源代碼編譯成字節碼，2)字節碼由JVM解釋執行，3)JVM提供內存管理和垃圾回收功能，確保程序在不同操作系統上運行。
MongoDB集群在CentOS上如何搭建
Apr 14, 2025 pm 06:30 PM
在CentOS系統上搭建MongoDB集群，需要完成MongoDB安裝、實例配置、副本集設置以及分片等步驟。以下步驟將詳細指導您完成這一過程：一、準備工作確保CentOS系統已更新，並安裝必要的工具：sudoyumupdate-ysudoyuminstall-ywgetvim二、安裝MongoDB添加MongoDBYUM源:創建mongodb.repo文件，並添加MongoDB倉庫信息(版本號請根據實際情況調整):echo"[mongodb-org-4.4]n
