前言

在学了用MongoDB之后，总感觉直接操作那个客户端比较痛苦。咱是程序员啊，咱能干的就是将自己的想法以代码的形式展示出来。用Navicat连接MongoDB，那么就开始上java代码，毕竟SpringBoot不是白学的啊！！！！

开搞

1.创建完一个空的maven项目之后就开始导包了（springboot的MongoDB）。

    <dependency>
      <groupId>org.springframework.boot</groupId>
      <artifactId>spring-boot-starter-data-mongodb</artifactId>
    </dependency>

2.在src/main/resource下创建一个application.yml

server:
  port: 9006  #端口自定义
spring:
  application:
    name: tensquare-spit     #项目的名称,可写可不写
  data:
    mongodb:
      host: localhost     #mongodb所在的那个主机，最好写成localhost或127.0.0.1或固定的IP，我在换了无线网之后报了个超时的错，还找了半天，看着配置都没错，就IP错了
      port: 27017            #开放的端口
      database: spitdb        #数据库名

3.创建实体类(包括get，set和toString)

import org.springframework.data.annotation.Id;

import java.io.Serializable;
import java.util.Date;
public class Spit implements Serializable {
  @Id //和_id相对应,自动映射为_id
  private String _id;
  private String content;
  private Date publishtime;
  private String userid;
  private String nickname;
  private Integer visits;
  private Integer thumbup;
  private Integer share;
  private Integer comment;
  private String state;
  private String parentid;

  //空参有参,get,set和toSring
    ....
}

4.创建Dao，从而操作数据库

import com.tensquare.spit.pojo.Spit;
import org.springframework.data.domain.Page;
import org.springframework.data.domain.Pageable;
import org.springframework.data.mongodb.repository.MongoRepository;

public interface SpitDao extends MongoRepository<Spit,String> {

  public Page<Spit> findByParentid(String parentid, Pageable pageable);

}

5.创建service层，用于操作 Dao

import com.tensquare.spit.dao.SpitDao;
import com.tensquare.spit.pojo.Spit;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.domain.Page;
import org.springframework.data.domain.PageRequest;
import org.springframework.data.domain.Pageable;
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.data.mongodb.core.query.Update;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.stereotype.Service;
import util.IdWorker;

import java.util.Date;
import java.util.List;

@Service
public class SpitService {

  @Autowired
  private SpitDao spitDao;//注入的Dao

  @Autowired
  private IdWorker idWorker;//用于动态生成id

  @Autowired
  private MongoTemplate mongoTemplate;//使用的Mongo的模板,在springboot整合mongodb的时候只用到了简单的逻辑,有些复杂的逻辑倒是需要自己用自带的模板写

//查找所有
  public List<Spit> findAll(){
    return spitDao.findAll();
  }
//通过id查询
  public Spit findById(String id){
    return spitDao.findById(id).get();
  }
//保存一个
  public void save(Spit spit){
    spit.set_id(String.valueOf(idWorker.nextId()));
    spit.setPublishtime(new Date());//发布日期
    spit.setVisits(0);//浏览量         
    spit.setShare(0);//分享数         
    spit.setThumbup(0);//点赞数         
    spit.setComment(0);//回复数         
    spit.setState("1");//状态
    System.out.println("parentid:"+spit.getParentid());
    spitDao.save(spit);
    //如果当前添加的吐槽有父节点,那么父节点的吐槽数+1
    if (spit.getParentid() != null && !"".equals(spit.getParentid())){
      Query query = new Query();
      query.addCriteria(Criteria.where("_id").is(spit.get_id()));
      Update update = new Update();
      update.inc("comment",1);
      mongoTemplate.updateFirst(query,update,"spit");
      System.out.println("comment:"+spit.getComment());
    }
    System.out.println(spit);
  }
//更新一个
  public void update(Spit spit){
     spitDao.save(spit);
  }
//通过id删除一个
  public void deleteById(String id){
    spitDao.deleteById(id);
  }
//分页
  public Page<Spit> findPage(int page,int size){
    PageRequest of = PageRequest.of(page-1, size);
    return spitDao.findAll(of);
  }
//通过某些条件分页
  public Page<Spit> findByParentid(String parentid, int page,int size){
    PageRequest of = PageRequest.of(page-1, size);
    return spitDao.findByParentid(parentid,of);
  }
//通过id更新一条数据的字段
  public void thumbupById(String id){
    Query query = new Query();
    query.addCriteria(Criteria.where("_id").is(id));
    Update update = new Update();
    update.inc("thumbup",1);
    mongoTemplate.updateFirst(query,update,"spit");
  }
}

6.创建controller，用以和service进行交互

import com.tensquare.spit.pojo.Spit;
import com.tensquare.spit.service.SpitService;
import entity.PageResult;
import entity.Result;
import entity.StatusCode;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.domain.Page;
import org.springframework.data.domain.PageRequest;
import org.springframework.data.domain.Sort;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.data.web.PageableDefault;
import org.springframework.web.bind.annotation.CrossOrigin;
import org.springframework.web.bind.annotation.DeleteMapping;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.PutMapping;
import org.springframework.web.bind.annotation.RequestBody;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.bind.annotation.RestController;

import java.util.List;

@RestController //两个注解的合体
@CrossOrigin //用于跨域
@RequestMapping("/spit")
public class SpitController {

  @Autowired
  private SpitService spitService;
  @Autowired
  private RedisTemplate redisTemplate;

  @GetMapping("findAll")
  public Result findAll() {
    return new Result(true, StatusCode.OK, "查找成功", spitService.findAll());
  }

  @GetMapping("findById/{id}")
  public Result findById(@PathVariable String id) {
    return new Result(true, StatusCode.OK, "查找成功", spitService.findById(id));
  }

  @PostMapping("saveOne")
  public Result save(@RequestBody Spit spit) {
    spitService.save(spit);
    return new Result(true, StatusCode.OK, "添加成功");
  }

  @PutMapping("updateOne")
  public Result update(@RequestBody Spit spit) {
    spitService.update(spit);
    return new Result(true, StatusCode.OK, "修改成功");
  }


  @DeleteMapping("deleteById/{id}")
  public Result deleteById(@PathVariable String id) {
    spitService.deleteById(id);
    return new Result(true, StatusCode.OK, "删除成功");
  }

  @GetMapping("findPage/{page}/{size}")
  public Result findPage(@PageableDefault(sort = {"id"}, direction = Sort.Direction.DESC) @PathVariable int page, @PathVariable int size) {
    Page<Spit> page1 = spitService.findPage(page, size);
    return new Result(true, StatusCode.OK, "查找成功", new PageResult<>(page1.getTotalElements(), page1.getContent()));
  }


  @GetMapping("findByParentid/{parentid}/{page}/{size}")
  public Result findByParentid(@PathVariable String parentid, @PathVariable int page, @PathVariable int size) {
    Page<Spit> byParentid = spitService.findByParentid(parentid, page, size);
    return new Result(true, StatusCode.OK, "查找成功", new PageResult<>(byParentid.getTotalElements(), byParentid.getContent()));
  }

  @PutMapping("thumbup/{spitid}")
  public Result thumbupById(@PathVariable String spitid) {
    //判断当前是否已经点赞,还没做认证,暂时把user写死
    String userid = "111111";
    if (redisTemplate.opsForValue().get("thumbup_" + userid) != null) {
      return new Result(true, StatusCode.REPERROR, "不能重复点赞");
    }
    spitService.thumbupById(spitid);
    redisTemplate.opsForValue().set("thumbup_" + userid, 1);
    return new Result(true, StatusCode.OK, "点赞成功");
  }
}

7.数据库图片