MongoDB学习-->Gridfs分布式存储&DBRef关联查询

mongodb自带的一个分布式文件系统

fs.files _id filename md5 size uploaddate contenttype metadata {"user_id":1}

fs.chunks _id files_id n(序号) data

{ "metadata" : { "user_id" : 101} , "filename" : "video.min2.js" , "aliases" : null , "chunkSize" : 261120 , "uploadDate" : { "$date" : "2017-03-28T13:48:20.784Z"} , "length" : 282753 , "_id" : { "$oid" : "58da69a45aa6c70234eb70f1"} , "contentType" : null , "md5" : "e5ab0872d9b25fcb7268df3a93c29873"}

测试GridFs文件上传与下载

 package com.tangzhe.gridfs;

 import com.mongodb.BasicDBObject;
 import com.mongodb.gridfs.GridFSDBFile;
 import com.mongodb.gridfs.GridFSFile;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.boot.test.context.SpringBootTest;
 import org.springframework.data.mongodb.core.query.Criteria;
 import org.springframework.data.mongodb.core.query.Query;
 import org.springframework.data.mongodb.gridfs.GridFsTemplate;
 import org.springframework.test.context.junit4.SpringRunner;

 import java.io.File;
 import java.io.FileInputStream;
 import java.io.FileNotFoundException;
 import java.io.IOException;

 /**
  * Created by 唐哲
  * 2018-03-15 9:33
  * 测试GridFs文件上传与下载
  */
 @RunWith(SpringRunner.class)
 @SpringBootTest
 public class GridFsTest {

     @Autowired
     private GridFsTemplate gridFsTemplate;

     /**
      * 测试GridFs文件上传
      */
     //@Test
     public void gridFsUpload() throws FileNotFoundException {
         //System.out.println(gridFsTemplate);
         File file = new File("D:\\IdeaProjects\\cxytiandi\\mongodb-demo\\upload.txt");
         GridFSFile gridFSFile = gridFsTemplate.store(new FileInputStream(file), file.getName(), new BasicDBObject("user_id", 101));
         System.out.println(gridFSFile.toString());
     }

     /**
      * 测试GridFs文件下载
      */
     //@Test
     public void gridFsDownload() throws IOException {
         GridFSDBFile gridFSDBFile = gridFsTemplate.findOne(Query.query(Criteria.where("_id").is("5aa9cf31d678412b40ff5ab4")));
         gridFSDBFile.writeTo("D:\\IdeaProjects\\cxytiandi\\mongodb-demo\\download.txt");
     }

 }

DBRef关联查询

 package com.tangzhe.dbref;

 import lombok.Data;
 import org.springframework.data.annotation.Id;
 import org.springframework.data.mongodb.core.mapping.Document;

 /**
  * Created by 唐哲
  * 2018-03-15 16:19
  * DBRef关联查询
  */
 @Document(collection = "class_info")
 @Data
 public class ClassInfo {

     @Id
     private String id;
     private String name;

 }

 package com.tangzhe.dbref;

 import lombok.Data;
 import org.springframework.data.annotation.Id;
 import org.springframework.data.mongodb.core.mapping.DBRef;
 import org.springframework.data.mongodb.core.mapping.Document;

 /**
  * Created by 唐哲
  * 2018-03-15 16:29
  * DBRef关联查询
  */
 @Document(collection = "student")
 @Data
 public class Student {

     @Id
     private String id;
     private String name;
     @DBRef
     private ClassInfo classInfo;

 }

 package com.tangzhe.dbref;

 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.boot.test.context.SpringBootTest;
 import org.springframework.data.mongodb.core.MongoTemplate;
 import org.springframework.data.mongodb.core.query.Criteria;
 import org.springframework.data.mongodb.core.query.Query;
 import org.springframework.test.context.junit4.SpringRunner;

 /**
  * Created by 唐哲
  * 2018-03-15 16:30
  * 测试DBRef关联查询
  */
 @RunWith(SpringRunner.class)
 @SpringBootTest
 public class DbRefTest {

     @Autowired
     private MongoTemplate mongoTemplate;

     //@Test
     public void test1() {
         ClassInfo classInfo = new ClassInfo();
         classInfo.setName("三年一班");
         mongoTemplate.save(classInfo);

         Student student = new Student();
         student.setName("张三");
         student.setClassInfo(classInfo);
         mongoTemplate.save(student);
     }

     //@Test
     public void test2() {
         ClassInfo classInfo = mongoTemplate.findOne(Query.query(Criteria.where("id").is("5aaa30c0d678410bac20db1a")), ClassInfo.class);
         Student student = new Student();
         student.setName("李四");
         student.setClassInfo(classInfo);
         mongoTemplate.save(student);
     }

     //@Test
     public void test3() {
         Student student = mongoTemplate.findOne(Query.query(Criteria.where("id").is("5aaa30c0d678410bac20db1b")), Student.class);
         System.out.println(student);
     }

 }