架构实战项目心得（七）：使用SpringBoot+Dubbo+Mybatisplus+Oracle搭建后台项目框架（二）

接下来我们将整合mybatisplus+Oracle，实现一个简单的查询。（期间踩了很多坑，遇到一些问题，还好慢慢解决了。现在是通过配置文件的方式来进行dubbo服务的注册和发布，希望以后能在学习和实践中使用springboot注解方式（也有可能是因为知识还没到那个层面，无法弄懂其中的奥义

））
一、SpringBoot整合mybatisplus
    1 众所周知，mybatisplus作为mybatis的一个升级版，大大地简化了大家配置mybatis的xml文件的时间，并且已经整合了很多通用的方法，包括分页的方法等，本项目不细讲mybatisplus，有兴趣的同学可以自己去学一下。本次项目使用mybatisplus作为后台数据库访问的框架。

    2 mybatisplus和mybatisplus的SpringBoot依赖：<!--mybatisplus 依赖 -->
<dependency>
<groupId>com.baomidou</groupId>
<artifactId>mybatis-plus</artifactId>
<version>${mybatisplus.version}</version>
</dependency>
<!-- Mybatisplus SpringBoot-->
<dependency>
<groupId>com.baomidou</groupId>
<artifactId>mybatisplus-spring-boot-starter</artifactId>
<version>${mybatisplus-spring-boot-starter.version}</version>
</dependency>
    具体的版本根据你的需求来定。
    3 对应的实体类UserEntity：@TableName("USER_INFO")
public class UserEntity extends Model<UserEntity> {
@TableId(value = "USER_ID",type = IdType.AUTO)
private Integer userId;
private String username;
private String password;
private Integer age;
protected Serializable pkVal() {
return userId;
}

public Integer getUserId() {
return userId;
}

public void setUserId(Integer userId) {
this.userId = userId;
}

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 Integer getAge() {
return age;
}

public void setAge(Integer age) {
this.age = age;
}

@Override
public String toString() {
return "UserEntity{" +
"userId=" + userId +
", username='" + username + '\'' +
", password='" + password + '\'' +
", age=" + age +
'}';
}

public UserEntity(Integer userId, String username, String password, Integer age) {
this.userId = userId;
this.username = username;
this.password = password;
this.age = age;
}

public UserEntity() {
}    4 Mapper层UserMapper：public interface UserMapper extends BaseMapper<UserEntity>{
Integer getCount();
}    5 UserMapper.xml：
    
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.laowang.mapper.UserMapper">
<resultMap id="userMap" type="com.laowang.entity.UserEntity">
<result column="USER_ID" property="userId"></result>
<result column="USERNAME" property="username"></result>
<result column="PASSWORD" property="password"></result>
<result column="AGE" property="age"></result>
</resultMap>
<select id="getCount" resultType="java.lang.Integer">
SELECT COUNT(1) FROM USER_INFO
</select>
</mapper>    6 服务接口层IUserService：public interface IUserService extends IService<UserEntity> {
UserEntity getUserById(int id);
UserEntity findUser();
/**
* 查询总数量
* @return
*/
Integer getCount();
}
    7 服务接口实现层UserServiceImpl：@Service
public class UserServiceImpl extends ServiceImpl<UserMapper,UserEntity> implements IUserService {
@Autowired
private UserMapper userMapper;

public UserEntity getUserById(int id) {
return userMapper.selectById(id);
}

public UserEntity findUser() {
return new UserEntity(20,"laowang","123456789",24);
}

public Integer getCount() {
return userMapper.getCount();
}
}    8 控制层UserController：@RestController
public class UserController {
@Autowired
private IUserService userService;

@GetMapping("/getUser/{id}")
public UserEntity getUser(@PathVariable int id) {
return userService.getUserById(id);
}

@GetMapping("/test")
public UserEntity findUser() {
return userService.findUser();
}

@GetMapping("/getCount")
public Integer getCount() {
return userService.getCount();
}
}9 application.yml：# Dubbo 服务提供者配置
server:
port: 8070
spring:
application:
name: provider
datasource:
url: jdbc:oracle:thin:@127.0.0.1:1521:hadoop
username: sys as sysdba
password: 123456789
driver-class-name: oracle.jdbc.driver.OracleDriver
type: com.alibaba.druid.pool.DruidDataSource
initialSize: 5
minIdle: 5
maxActive: 20
maxWait: 60000
timeBetweenEvictionRunsMillis: 60000
minEvictableIdleTimeMillis: 300000
validationQuery: SELECT 1 FROM DUAL
testWhileIdle: true
testOnBorrow: false
testOnReturn: false
poolPreparedStatements: true
maxPoolPreparedStatementPerConnectionSize: 20
filters: stat,wall,logback
connectionProperties: druid.stat.mergeSql=true;druid.stat.slowSqlMillis=5000
useGlobalDataSourceStat: true
mybatis:
mapper-locations: classpath:mapper/*Mapper.xml
#实体扫描，多个package用逗号或者分号分隔
type-aliases-package: com.laowang.entity10 运行项目进行测试，即可得到一个简单的查询结果（由于我的项目已经分割了，所以这里暂时看不到效果，希望大家按照我的步骤去尝试，能够得到一个简答的查询）