03SpringBoot用JdbcTemplates訪問Mysql

03SpringBoot用JdbcTemplates訪問Mysql

• 文章指導
• 學習筆記
• 學習代碼

1. 初始化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');

1. 引入依賴

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

<!--引入mysql鏈接類和鏈接池-->

<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>

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

1. 在application.properties文件配置mysql的驅動類，數據庫地址，數據庫帳號、密碼信息。

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

1. 實體類

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

....省略了getter. setter

}

1. dao層

public interface IAccountDAO {
    int add(Account account);

    int update(Account account);

    int delete(int id);

    Account findAccountById(int id);

    List<Account> findAccountList();
}

1. dao具體的實現類

@Repository  // 注意加這個註解
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;
        }
    }
}

1. service層

public interface IAccountService {


    int add(Account account);

    int update(Account account);

    int delete(int id);

    Account findAccountById(int id);

    List<Account> findAccountList();

}

1. service具體實現類

@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();
    }
}

1. 構建一組restful api來展現

@RestController
@RequestMapping("/account") // rest規範： /實體
public class AccountController {

    @Autowired
    IAccountService accountService;

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

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

    // rest規範使用Put修改
    @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";
        }
    }

    // rest規範使用post新增
    @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";
        }

    }

}

1. 啓動項目，經過postman來測試