Springboot用idea写查询数据库程序（详细讲解）
先把代码给大家详细贴以下
首先是连接数据库的application.properties
root和15235068202 是我的账号和密码 8888是访问的端口号 school是我的数据库的 库名字
spring.datasource.url = jdbc:mysql://localhost:3306/school?useUnicode=true&characterEncoding=utf-8&useSSL=false&serverTimezone=GMT%2B8
spring.datasource.username = root
spring.datasource.password = 15235068202
spring.datasource.driverClassName = com.mysql.jdbc.Driver
server.port=8888
mybatis.mapper-locations=classpath:mapper/*.xml
#spring.mvc.static-path-pattern=/static/**
#logging.level.com.example.thecloudsystem.dao=debug
#logging.level.org.springframework.security=info
logging.level.mapper=DEBUG
#logging.level.com.example.syscloud.dao=DEBUG
# REDIS (RedisProperties)
# Redis数据库索引（默认为0）
spring.thymeleaf.enabled=true
需要引入的依赖pom.xml
4.0.0
org.springframework.boot
spring-boot-starter-parent
2.2.0.BUILD-SNAPSHOT
com.example
schools
0.0.1-SNAPSHOT
schools
Demo project for Spring Boot
1.8
org.springframework.boot
spring-boot-starter-jdbc
org.springframework.boot
spring-boot-starter-thymeleaf
org.springframework.boot
spring-boot-starter-web
javax.servlet
javax.servlet-api
provided
org.mybatis.spring.boot
mybatis-spring-boot-starter
1.3.2
org.springframework.boot
spring-boot-starter-thymeleaf
mysql
mysql-connector-java
5.1.38
org.springframework.boot
spring-boot-starter-test
test
com.github.fge
json-schema-core
1.2.5
com.alibaba
fastjson
1.2.47
com.google.guava
guava
27.0-jre
com.fasterxml.jackson.core
jackson-core
2.9.7
org.projectlombok
lombok
1.16.20
provided
com.github.penggle
kaptcha
2.3.2
com.auth0
java-jwt
3.3.0
org.quartz-scheduler
quartz
${quartz.version}
org.quartz-scheduler
quartz-jobs
${quartz.version}
org.testng
testng
RELEASE
compile
org.springframework.boot
spring-boot-starter-data-jpa
org.springframework.boot
spring-boot-maven-plugin
spring-snapshots
Spring Snapshots
https://repo.spring.io/snapshot
true
spring-milestones
Spring Milestones
https://repo.spring.io/milestone
spring-snapshots
Spring Snapshots
https://repo.spring.io/snapshot
true
spring-milestones
Spring Milestones
https://repo.spring.io/milestone
再简单的贴下我的数据库 从数据直接导出的数据
/*
Navicat MySQL Data Transfer
Source Server : localhost
Source Server Version : 50703
Source Host : 127.0.0.1:3306
Source Database : school
Target Server Type : MYSQL
Target Server Version : 50703
File Encoding : 65001
Date: 2019-06-19 17:45:01
*/
SET FOREIGN_KEY_CHECKS=0;
-- ----------------------------
-- Table structure for user
-- ----------------------------
DROP TABLE IF EXISTS `user`;
CREATE TABLE `user` (
`id` int(11) NOT NULL AUTO_INCREMENT,
`name` varchar(20) NOT NULL,
`password` varchar(20) NOT NULL,
PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=4 DEFAULT CHARSET=utf8;
-- ----------------------------
-- Records of user
-- ----------------------------
INSERT INTO `user` VALUES ('1', 'root', '123456');
INSERT INTO `user` VALUES ('2', 'httl', '554952');
INSERT INTO `user` VALUES ('3', '刘俊', '3');
接下来给大家看下 都需要那些类
实体类userBean
get/set 方法
package com.example.demo4.userBean;
import javax.persistence.Entity;
import javax.persistence.Id;
// @Entity 对实体注释。任何Hibernate映射对象都要有这个注释
// @Id 声明此属性为主键。该属性值可以通过应该自身创建
//实体类
@Entity
public class userBean {
@Id
private Integer id;
private String name;
private String password;
public userBean(Integer id, String name,String password) {
this.id=id;
this.name = name;
this.password=password;
}
public Integer getId() {
return id;
}
public void setId(Integer id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
}
mapper的数据库语句
id,name,password
userDao 数据源文件
package com.example.demo4.userDao;
import com.example.demo4.userBean.userBean;
import org.apache.ibatis.annotations.Mapper;
import org.springframework.stereotype.Repository;
import java.util.List;
import java.util.Map;
//数据源文件
@Repository
@Mapper
public interface UserDao {
List select(Map userMap);
}
service 业务层
package com.example.demo4.service;
import com.example.demo4.userBean.userBean;
import java.util.List;
import java.util.Map;
public interface service {
List select(Map userMap);
}
serviceimpl
业务实现层
package com.example.demo4.service;
import com.example.demo4.userBean.userBean;
import com.example.demo4.userDao.UserDao;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import java.util.List;
import java.util.Map;
@Service
public class servielimpl implements service {
@Autowired
private UserDao userDao;
@Override
public List select(Map userMap) {
return userDao.select(userMap);
}
}
testController 直接访问返回
package com.example.demo4.Controller;
import com.example.demo4.service.service;
import com.example.demo4.userBean.userBean;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.bind.annotation.RestController;
import javax.servlet.http.HttpServletRequest;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
//@Controller
@RestController
public class testController {
@Autowired
private service service;
@RequestMapping("/aaa")
public String sayHello() {
return "helloword";
}
testController 直接查询数据库数据
package com.example.demo4.Controller;
import com.example.demo4.service.service;
import com.example.demo4.userBean.userBean;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.bind.annotation.RestController;
import javax.servlet.http.HttpServletRequest;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
//@Controller
@RestController
public class testController {
@Autowired
private service service;
@RequestMapping("/aaa")
public String sayHello() {
return "helloword";
}
@RequestMapping(value = "/fu")
@ResponseBody
public List fuzzyCUser(HttpServletRequest request) {
Map result = new HashMap<>();
Listlist =service.select(result);
// result.put("list",list);
request.getSession().setAttribute("LIST",list);
// return result;
return list;
}
testController 访问list输出的数据
package com.example.demo4.Controller;
import com.example.demo4.service.service;
import com.example.demo4.userBean.userBean;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.bind.annotation.RestController;
import javax.servlet.http.HttpServletRequest;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
//@Controller
@RestController
public class testController {
@Autowired
private service service;
@RequestMapping("/aaa")
public String sayHello() {
return "helloword";
}
// @RequestMapping(value = "/fu")
// @ResponseBody
// public List fuzzyCUser(HttpServletRequest request) {
// Map result = new HashMap<>();
// Listlist =service.select(result);
// // result.put("list",list);
// request.getSession().setAttribute("LIST",list);
// // return result;
// return list;
//
//
// }
@RequestMapping(value = "/fuss")
@ResponseBody
public Map fuzzyCUser(HttpServletRequest request) {
Map result = new HashMap<>();
List list = service.select(result);
result.put("list", list);
request.getSession().setAttribute("LIST", list);
return result;
}
}
这样查询就出来了 大家有意见和问题的可以提出来 欢迎讨论。
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