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package utils;
import java.net.UnknownHostException;
import java.util.ArrayList;
import java.util.List;
import org.bson.Document;
import org.bson.conversions.Bson;
import org.bson.types.ObjectId;
import com.mongodb.BasicDBObject;
import com.mongodb.MongoClient;
import com.mongodb.MongoClientOptions;
import com.mongodb.MongoClientOptions.Builder;
import com.mongodb.WriteConcern;
import com.mongodb.client.MongoCollection;
import com.mongodb.client.MongoCursor;
import com.mongodb.client.MongoDatabase;
import com.mongodb.client.MongoIterable;
import com.mongodb.client.model.Filters;
import com.mongodb.client.result.DeleteResult;
/**
* MongoDB工具类 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<br>
* 注意Mongo已经实现了连接池,并且是线程安全的。 <br>
* 设计为单例模式, 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,<br>
* Mongo有个内置的连接池(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,<br>
* DB和DBCollection是绝对线程安全的<br>
*
*
@author gonglei 使用mongo-java-driver-3.0.2连接MongoDB数据库
* @date 2017-3-16
*
@version 0.0.0
* @Copyright (c)2017-2018
*/
public enum MongoDBUtil {
/**
* 定义一个枚举的元素,它代表此类的一个实例
*/
instance;
private MongoClient mongoClient;
static {
System.out.println("===============MongoDBUtil初始化========================");
/*
CompositeConfiguration config = new CompositeConfiguration();
try {
config.addConfiguration(new PropertiesConfiguration("mongodb.properties"));
} catch (ConfigurationException e) {
e.printStackTrace();
}
*/
// 从配置文件中获取属性值
String ip = utils.getWriteProperties.GetValueByKey("db.properties", "host");
int port = Integer.parseInt(utils.getWriteProperties.GetValueByKey("db.properties", "port"));
// //默认写死
// String ip ="127.0.0.1";
// int port=27017;
instance.mongoClient = new MongoClient(ip, port);
// or, to connect to a replica set, with auto-discovery of the primary, supply a seed list of members
// List<ServerAddress> listHost = Arrays.asList(new ServerAddress("localhost", 27017),new ServerAddress("localhost", 27018));
// instance.mongoClient = new MongoClient(listHost);
// 大部分用户使用mongodb都在安全内网下,但如果将mongodb设为安全验证模式,就需要在客户端提供用户名和密码:
// boolean auth = db.authenticate(myUserName, myPassword);
Builder options = new MongoClientOptions.Builder();
// options.autoConnectRetry(true);// 自动重连true
// options.maxAutoConnectRetryTime(10); // the maximum auto connect retry time
options.connectionsPerHost(300);// 连接池设置为300个连接,默认为100
options.connectTimeout(15000);// 连接超时,推荐>3000毫秒
options.maxWaitTime(5000); //
options.socketTimeout(0);// 套接字超时时间,0无限制
options.threadsAllowedToBlockForConnectionMultiplier(5000);// 线程队列数,如果连接线程排满了队列就会抛出“Out of semaphores to get db”错误。
options.writeConcern(WriteConcern.SAFE);//
options.build();
}
// -----------------------------------共用方法---------------------------------------------------
/**
* 获取DB实例 - 指定DB
*
* @param dbName
* @return
*/
public MongoDatabase getDB(String dbName) {
if (dbName != null && !"".equals(dbName)) {
MongoDatabase database = mongoClient.getDatabase(dbName);
return database;
}
return null;
}
/**
* 获取collection对象 - 指定Collection
*
* @param collName
* @return
*/
public MongoCollection<Document> getCollection(String dbName, String collName) {
if (null == collName || "".equals(collName)) {
return null;
}
if (null == dbName || "".equals(dbName)) {
return null;
}
MongoCollection<Document> collection = mongoClient.getDatabase(dbName).getCollection(collName);
return collection;
}
/**
* 查询DB下的所有表名
*/
public List<String> getAllCollections(String dbName) {
MongoIterable<String> colls = getDB(dbName).listCollectionNames();
List<String> _list = new ArrayList<String>();
for (String s : colls) {
_list.add(s);
}
return _list;
}
/**
* 获取所有数据库名称列表
*
* @return
*/
public MongoIterable<String> getAllDBNames() {
MongoIterable<String> s = mongoClient.listDatabaseNames();
return s;
}
/**
* 删除一个数据库
*/
public void dropDB(String dbName) {
getDB(dbName).drop();
}
/**
* 查找对象 - 根据主键_id
*
* @param collection
* @param>
* @return
*/
public Document findById(MongoCollection<Document> coll, String>
ObjectId _idobj = null;
try {
_idobj = new ObjectId(id);
} catch (Exception e) {
return null;
}
Document myDoc = coll.find(Filters.eq("_id", _idobj)).first();
return myDoc;
}
/** 统计数 */
public int getCount(MongoCollection<Document> coll) {
int count = (int) coll.count();
return count;
}
/** 条件查询 */
public MongoCursor<Document> find(MongoCollection<Document> coll, Bson filter) {
return coll.find(filter).iterator();
}
/** 分页查询 */
public MongoCursor<Document> findByPage(MongoCollection<Document> coll, Bson filter, int pageNo, int pageSize) {
Bson orderBy = new BasicDBObject("_id", 1);
return coll.find(filter).sort(orderBy).skip((pageNo - 1) * pageSize).limit(pageSize).iterator();
}
/**
* 通过ID删除
*
* @param coll
* @param>
* @return
*/
public int deleteById(MongoCollection<Document> coll, String>
int count = 0;
ObjectId _id = null;
try {
_id = new ObjectId(id);
} catch (Exception e) {
return 0;
}
Bson filter = Filters.eq("_id", _id);
DeleteResult deleteResult = coll.deleteOne(filter);
count = (int) deleteResult.getDeletedCount();
return count;
}
/**
* FIXME
*
* @param coll
* @param>
* @param newdoc
* @return
*/
public Document updateById(MongoCollection<Document> coll, String>
ObjectId _idobj = null;
try {
_idobj = new ObjectId(id);
} catch (Exception e) {
return null;
}
Bson filter = Filters.eq("_id", _idobj);
// coll.replaceOne(filter, newdoc); // 完全替代
coll.updateOne(filter, new Document("$set", newdoc));
return newdoc;
}
public void dropCollection(String dbName, String collName) {
getDB(dbName).getCollection(collName).drop();
}
/**
* 关闭Mongodb
*/
public void close() {
if (mongoClient != null) {
mongoClient.close();
mongoClient = null;
}
System.out.println("===============MongoDBUtil关闭连接========================");
} |
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