SpringBoot Unofficial Tutorial | Part 3: SpringBoot uses JdbcTemplates to access Mysql

Please indicate the source for reprinting: 
http://blog.csdn.net/forezp/article/details/70477821 
This article is from Fang Zhipeng's blog

This article introduces that springboot accesses relational mysql through jdbc and accesses it through spring's JdbcTemplate.

Ready to work

• jdk 1.8
• maven 3.0
• idea
• mysql

Initialize mysql:

-- create table `account`
DROP TABLE `account` IF EXISTS
CREATE TABLE `account` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `name` varchar(20) NOT NULL,
  `money` double DEFAULT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=4 DEFAULT CHARSET=utf8;
INSERT INTO `account` VALUES ('1', 'aaa', '1000');
INSERT INTO `account` VALUES ('2', 'bbb', '1000');
INSERT INTO `account` VALUES ('3', 'ccc', '1000');

Create project

Import dependencies:

Introduce the dependency of spring-boot-starter-jdbc in the pom file:

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

Introduce mysql connection class and connection pool:

<dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <scope>runtime</scope>
        </dependency>

        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>druid</artifactId>
            <version>1.0.29</version>
        </dependency>

Open web:

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

Configuration related files

Configure the mysql driver class, database address, database account, and password information in the application.properties file.

spring.datasource.driver-class-name=com.mysql.jdbc.Driver
spring.datasource.url=jdbc:mysql://localhost:3306/test
spring.datasource.username=root
spring.datasource.password=123456

By introducing these dependencies and configuring some basic information, springboot can access database classes.

specific code

entity class

public class Account {
    private int id ;
    private String name ;
    private double money;

....省略了getter. setter

}

dao layers

public interface IAccountDAO {
    int add(Account account);

    int update(Account account);

    int delete(int id);

    Account findAccountById(int id);

    List<Account> findAccountList();
}

The specific implementation class:

package com.forezp.dao.impl;

import com.forezp.dao.IAccountDAO;
import com.forezp.entity.Account;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.jdbc.core.BeanPropertyRowMapper;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.stereotype.Repository;

import java.util.List;

/**
 * Created by fangzhipeng on 2017/4/20.
 */
@Repository
public class AccountDaoImpl implements IAccountDAO {

    @Autowired
    private JdbcTemplate jdbcTemplate;
    @Override
    public int add(Account account) {
        return jdbcTemplate.update("insert into account(name, money) values(?, ?)",
              account.getName(),account.getMoney());

    }

    @Override
    public int update(Account account) {
        return jdbcTemplate.update("UPDATE  account SET NAME=? ,money=? WHERE id=?",
                account.getName(),account.getMoney(),account.getId());
    }

    @Override
    public int delete(int id) {
        return jdbcTemplate.update("DELETE from TABLE account where id=?",id);
    }

    @Override
    public Account findAccountById(int id) {
        List<Account> list = jdbcTemplate.query("select * from account where id = ?", new Object[]{id}, new BeanPropertyRowMapper(Account.class));
        if(list!=null && list.size()>0){
            Account account = list.get(0);
            return account;
        }else{
            return null;
        }
    }

    @Override
    public List<Account> findAccountList() {
        List<Account> list = jdbcTemplate.query("select * from account", new Object[]{}, new BeanPropertyRowMapper(Account.class));
        if(list!=null && list.size()>0){
            return list;
        }else{
            return null;
        }
    }
}

service layer

public interface IAccountService {


    int add(Account account);

    int update(Account account);

    int delete(int id);

    Account findAccountById(int id);

    List<Account> findAccountList();

}

Concrete implementation class:

@Service
public class AccountService implements IAccountService {
    @Autowired
    IAccountDAO accountDAO;
    @Override
    public int add(Account account) {
        return accountDAO.add(account);
    }

    @Override
    public int update(Account account) {
        return accountDAO.update(account);
    }

    @Override
    public int delete(int id) {
        return accountDAO.delete(id);
    }

    @Override
    public Account findAccountById(int id) {
        return accountDAO.findAccountById(id);
    }

    @Override
    public List<Account> findAccountList() {
        return accountDAO.findAccountList();
    }
}

Build a set of restful APIs to showcase

package com.forezp.web;

import com.forezp.entity.Account;
import com.forezp.service.IAccountService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.*;

import java.util.List;

/**
 * Created by fangzhipeng on 2017/4/20.
 */

@RestController
@RequestMapping("/account")
public class AccountController {

    @Autowired
    IAccountService accountService;

    @RequestMapping(value = "/list",method = RequestMethod.GET)
    public  List<Account> getAccounts(){
       return accountService.findAccountList();
    }

    @RequestMapping(value = "/{id}",method = RequestMethod.GET)
    public  Account getAccountById(@PathVariable("id") int id){
        return accountService.findAccountById(id);
    }

    @RequestMapping(value = "/{id}",method = RequestMethod.PUT)
    public  String updateAccount(@PathVariable("id")int id , @RequestParam(value = "name",required = true)String name,
    @RequestParam(value = "money" ,required = true)double money){
        Account account=new Account();
        account.setMoney(money);
        account.setName(name);
        account.setId(id);
        int t=accountService.update(account);
        if(t==1){
            return account.toString();
        }else {
            return "fail";
        }
    }

    @RequestMapping(value = "",method = RequestMethod.POST)
    public  String postAccount( @RequestParam(value = "name")String name,
                                 @RequestParam(value = "money" )double money){
        Account account=new Account();
        account.setMoney(money);
        account.setName(name);
        int t= accountService.add(account);
        if(t==1){
            return account.toString();
        }else {
            return "fail";
        }

    }

}

It can be tested by postman. Specifically, I have passed all the tests without any problems. Pay attention to the style of restful build api.

Source code download: https://github.com/forezp/SpringBootLearning

References

relational-data-access