mongodb应用于java

mongodb-java-driver基本用法
1、先下载mongodb-java-driver 目前最新版本是2.9.3

2、下面是基本的CRUD示例代码:

复制代码
1 package com.cnblogs.yjmyzz.cache.test;
2
3 import com.google.gson.Gson;
4 import com.mongodb.BasicDBObject;
5 import com.mongodb.DB;
6 import com.mongodb.DBCollection;
7 import com.mongodb.DBCursor;
8 import com.mongodb.DBObject;
9 import com.mongodb.Mongo;
10 import com.mongodb.util.JSON;
11
12 import java.net.UnknownHostException;
13 import java.util.Calendar;
14 import java.util.Date;
15 import java.util.HashMap;
16 import java.util.HashSet;
17 import java.util.Map;
18 import java.util.Set;
19
20 import org.junit.Test;
21
22 public class TestMongoDriver {
23
24 @Test
25 public void testCRUD() throws UnknownHostException {
26 // 连接到mongodb
27 Mongo mongo = new Mongo(“localhost”, 27017);
28
29 // 打开数据库test
30 DB db = mongo.getDB(“test”);
31
32 // 遍历所有集合的名字
33 Set colls = db.getCollectionNames();
34 for (String s : colls) {
35 System.out.println(s);
36 // 先删除所有Collection(类似于关系数据库中的"表")
37 if (!s.equals(“system.indexes”)) {
38 db.getCollection(s).drop();
39 }
40 }
41
42 // 取得集合emp(若：emp不存在，mongodb将自动创建该集合)
43 DBCollection coll = db.getCollection(“emp”);
44
45 // delete all
46 DBCursor dbCursor = coll.find();
47 for (DBObject dbObject : dbCursor) {
48 coll.remove(dbObject);
49 }
50
51 // create
52 BasicDBObject doc = new BasicDBObject(“name”, “杨俊明”).append(“sex”, “男”)
53 .append(“address”,
54 new BasicDBObject(“postcode”, “201202”).append(
55 “street”, “田林路888号”).append(“city”, “上海”));
56 coll.insert(doc);
57
58 // retrieve
59 BasicDBObject docFind = new BasicDBObject(“name”, “杨俊明”);
60 DBObject findResult = coll.findOne(docFind);
61 System.out.println(findResult);
62
63 // update
64 doc.put(“sex”, “MALE”);// 把sex属性从"男"，改成"MALE"
65 coll.update(docFind, doc);
66 findResult = coll.findOne(docFind);
67 System.out.println(findResult);
68
69 coll.dropIndexes();// 先删除所有索引
70 // create index
71 coll.createIndex(new BasicDBObject(“name”, 1)); // 1代表升序
72
73 // 复杂对象
74 UserData userData = new UserData(“jimmy”, “123456”);
75 Set pets = new HashSet();
76 pets.add(“cat”);
77 pets.add(“dog”);
78 Map<String, String> favoriteMovies = new HashMap<String, String>();
79 favoriteMovies.put(“dragons”, “Dragons II”);
80 favoriteMovies.put(“avator”, “Avator I”);
81 userData.setFavoriteMovies(favoriteMovies);
82 userData.setPets(pets);
83 userData.setBirthday(getDate(1990, 5, 1));
84 BasicDBObject objUser = new BasicDBObject(“key”, “jimmy”).append(
85 “value”, toDBObject(userData));
86 coll.insert(objUser);
87 System.out.println(coll.findOne(objUser));
88 }
89
90 /**
91 * 将普通Object对象转换成mongodb的DBObject对象
92 *
93 * @param obj
94 * @return
95 /
96 private DBObject toDBObject(Object obj) {
97 Gson gson = new Gson();
98 String json = gson.toJson(obj);
99 return (DBObject) JSON.parse(json);
100 }
101
102 /*
103 * 获取指定日期
104 *
105 * @param year
106 * @param month
107 * @param day
108 * @return
109 */
110 private Date getDate(int year, int month, int day) {
111 Calendar calendar = Calendar.getInstance();
112 calendar.clear();
113 calendar.set(year, month - 1, day);
114 return calendar.getTime();
115
116 }
117
118 }
复制代码

其中，为了演示复杂对象的持久化，类UserData定义如下：

复制代码
package com.cnblogs.yjmyzz.cache.test;

import java.io.Serializable;
import java.util.Date;
import java.util.Map;
import java.util.Set;

public class UserData implements Serializable {

private static final long serialVersionUID = -4770493237851400594L;
private String userName;
private String password;
private Set<String> pets;
private Map<String, String> favoriteMovies;
private Date birthday;

public UserData() {
}

public UserData(String userName, String passWord) {
    this.userName = userName;
    this.password = passWord;
}

public String getUserName() {
    return userName;
}

public void setUserName(String userName) {
    this.userName = userName;
}

public String getPassword() {
    return password;
}

public void setPassword(String password) {
    this.password = password;
}

public Set<String> getPets() {
    return pets;
}

public void setPets(Set<String> pets) {
    this.pets = pets;
}

public Map<String, String> getFavoriteMovies() {
    return favoriteMovies;
}

public void setFavoriteMovies(Map<String, String> favoriteMovies) {
    this.favoriteMovies = favoriteMovies;
}

public Date getBirthday() {
    return birthday;
}

public void setBirthday(Date birthday) {
    this.birthday = birthday;
}

}
复制代码

运行效果如下：

emp
system.indexes
{ “_id” : { “ $KaTeX parse error: Expected 'EOF', got '}' at position 34: \dots4ec171e7f6980a"}̲ , "name" : "杨俊\dots$ oid” : “53d34795744ec171e7f6980a”} , “name” : “杨俊明” , “sex” : “MALE” , “address” : { “postcode” : “201202” , “street” : “田林路888号” , “city” : “上海”}}
{ “_id” : { “$oid” : “53d34796744ec171e7f6980b”} , “key” : “jimmy” , “value” : { “userName” : “jimmy” , “password” : “123456” , “pets” : [ “cat” , “dog”] , “favoriteMovies” : { “dragons” : “Dragons II” , “avator” : “Avator I”} , “birthday” : “May 1, 1990 12:00:00 AM”}}

延伸阅读：
mondodb-java-driver 官方在线文档

8天学通mongodb系列

MongoDB基本用法

搭建高可用的MongoDB集群（上）：MongoDB的配置与副本集

搭建高可用mongodb集群（二）—— 副本集

搭建高可用mongodb集群（三）—— 深入副本集内部机制
搭建高可用mongodb集群（四）—— 分片

作者：菩提树下的杨过
出处：http://yjmyzz.cnblogs.com
本文版权归作者和博客园共有，欢迎转载，但未经作者同意必须保留此段声明，且在文章页面明显位置给出原文连接，否则保留追究法律责任的权利。

猜你喜欢