[MongoDB]MongoDB与JAVA结合使用CRUD
汇总：
1. [MongoDB]安装MongoDB
2. [MongoDB]Mongo基本使用：
3. [MongoDB]MongoDB的优缺点及与关系型数据库的比较
4. [MongoDB]MongoDB与JAVA结合使用CRUD
使用起来也相当简单，由于MongoDB是类文件的数据库，所以其操作起来非常方便
首先下载相应的jar包，这里我直接使用Maven自动获取，以下为POM文件中的配置：
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.8.2</version>
</dependency>
<dependency>
<groupId>org.mongodb</groupId>
<artifactId>mongo-java-driver</artifactId>
<version>2.7.2</version>
</dependency>
一个MongoDb的jar包和Junit的jar包，即可
后面即可开始编写代码，直接在某个java类的main方法中调用即可：
public static void main(String[] args) throws Exception{
// 创建一个Mongo实例，默认使用本地"127.0.0.1", 27017
Mongo mongo1j = new Mongo();
// 使用IP+端口号创建
Mongo mongo = new Mongo("127.0.0.1", 27017);
// 得到所有数据库的名称
for(String name : mongo.getDatabaseNames()) {
System.out.println("dbName: " + name);
}
// 取得某个数据库，用于后续对数据库的操作
DB db = mongo.getDB("student");
for(String name : db.getCollectionNames()) {
System.out.println("collectionName: " + name);
}
// 取得对应的集合
DBCollection students = db.getCollection("student");
// 查询所有集合中的数据
DBCursor cur = students.find();
// 遍历集合中的所有内容
while(cur.hasNext()) {
System.out.println(cur.next());
}
System.out.println("cur.count(): " + cur.count());
System.out.println("cur.getCursorId(): " + cur.getCursorId());
System.out.println("JSON.serialize(): " + JSON.serialize(cur));
// DELETE操作
students.remove(new BasicDBObject("name", "yangjx"));
System.out.println("cur.count(): " + cur.count());
// ADD操作
DBObject student = new BasicDBObject();
student.put("name", "yangjx");
student.put("age", 55);
students.save(student);
System.out.println("cur.count(): " + cur.count());
// UPDATE操作
DBObject updateObj = new BasicDBObject();
updateObj.put("age", 30);
updateObj.put("name", "zhangGY");
updateObj.put("extra", "markHere");
students.update(new BasicDBObject("age", 30), updateObj);
System.out.println(JSON.serialize(students.find(new BasicDBObject("name", "zhangGY"))));
}
上述代码执行完成之后会打印出如下：
dbName: local
dbName: student
collectionName: colName
collectionName: student
collectionName: system.indexes
{ "_id" : { "$oid" : "555ae83a09668180fadccdeb"} , "age" : 30}
{ "_id" : { "$oid" : "555ae84009668180fadccdec"} , "name" : "zhangYC" , "age" : 29.0 , "sex" : true}
{ "_id" : { "$oid" : "555ae84709668180fadccded"} , "name" : "zhangYYQ" , "age" : 30.0 , "sex" : true}
{ "_id" : { "$oid" : "555aebdb09b332c5a188b620"} , "passwd" : "1234"}
{ "_id" : { "$oid" : "555d80d7b7a5042665b195ae"} , "name" : "yangjx" , "age" : 55}
cur.count(): 5
cur.getCursorId(): 0
JSON.serialize(): [ { "_id" : { "$oid" : "555ae83a09668180fadccdeb"} , "age" : 30} , { "_id" : { "$oid" : "555ae84009668180fadccdec"} , "name" : "zhangYC" , "age" : 29.0 , "sex" : true} , { "_id" : { "$oid" : "555ae84709668180fadccded"} , "name" : "zhangYYQ" , "age" : 30.0 , "sex" : true} , { "_id" : { "$oid" : "555aebdb09b332c5a188b620"} , "passwd" : "1234"} , { "_id" : { "$oid" : "555d80d7b7a5042665b195ae"} , "name" : "yangjx" , "age" : 55}]
cur.count(): 4
cur.count(): 5
[ { "_id" : { "$oid" : "555ae83a09668180fadccdeb"} , "age" : 30 , "name" : "zhangGY" , "extra" : "markHere"}]
参考：
http://www.cnblogs.com/hoojo/archive/2011/06/02/2068665.html
