javaweb各种框架组合案例(七)：springboot+jdbcTemplete+通用dao+restful

一、介绍

1.springboot是spring项目的总结+整合

　　当我们搭smm,ssh,ssjdbc等组合框架时，各种配置不胜其烦，不仅是配置问题，在添加各种依赖时也是让人头疼，关键有些jar包之间还会出现冲突，让你的项目出现难以解决的问题。基于这种情况，springboot横空出世，在考虑到Struts控制层框架有漏洞，springboot放弃（大多数企业同样如此）了Struts，转而代之是springMVC，不过，springboot是自动集成springMVC的，不需要任何配置，不需要任何依赖，直接使用各种控制层注解。springboot是springcloud的基础，是开启微服务时代的钥匙。

二、新建springboot工程

1. 使用idea2019新建project，选择spring Initializr，next

2. 填写坐标信息，next

3. Developer Tools选择Lombok， Web选择Spring Web Starter，SQL选择JDBC API、MySQL Driver，next

lombok是为了省去实体类中getter/setter方法，使之在运行时动态添加getter/setter

4. 填写项目名已经存放位置，finish

三、项目构建

1. 数据库准备（两张表，分别是user用户表和phone手机表，且是一对多关系）

create database ssdj;

CREATE TABLE `user` (
`id` int(11) NOT NULL AUTO_INCREMENT,
`password` varchar(255) DEFAULT NULL,
`username` varchar(255) DEFAULT NULL,
PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=2 DEFAULT CHARSET=utf8;

CREATE TABLE `phone` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `brand` varchar(255) DEFAULT NULL,
  `user_id` int(11) DEFAULT NULL,
  PRIMARY KEY (`id`),
  KEY `FK_8t3jhwmmlxpq3qcwcy1a3alts` (`user_id`),
  CONSTRAINT `FK_8t3jhwmmlxpq3qcwcy1a3alts` FOREIGN KEY (`user_id`) REFERENCES `user` (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=3 DEFAULT CHARSET=utf8;

insert into user(username,password) values(1001,123);

insert into phone(brand,user_id) values ('华为',1),('iphone',1);

2. pom.xml（不用动，默认）

3. 配置文件

　　application.properties

spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver
spring.datasource.url=jdbc:mysql://localhost:3306/ssdj?useUnicode=true&characterEncoding=utf-8&useSSL=false&serverTimezone=GMT
spring.datasource.username=root
spring.datasource.password=root

　　数据库连接要添加时区，否则可能会报错

4.项目包结构

　　分成util、core、entity、dao、service、controller等结构包

5. 需要一个SqlFactory工具类来制造动态SQL语句

package club.xcreeper.springboot_jdbctemplete.util;

import java.lang.reflect.Field;
import java.util.HashMap;
import java.util.Map;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

public class SqlFactory {

    private String tableName;

    public Object[] params;

    public SqlFactory(Class<?> clazz) {
        tableName = clazz.getSimpleName().toLowerCase();
    }

    private final static Logger logger = LoggerFactory.getLogger(SqlFactory.class);

    private Map<String,Object> objectToMap(Object entity) {
        Field[] fields = entity.getClass().getDeclaredFields();
        Map<String,Object> map = new HashMap<String,Object>();
        for(Field field : fields) {
            field.setAccessible(true);//允许访问属性
            Object value = null;
            try {
                value = field.get(entity);
            } catch (IllegalArgumentException | IllegalAccessException e) {
                e.printStackTrace();
            }
            if(value != null) {
                map.put(field.getName(), value);
            }
        }
        return map;
    }

    public String getDeleteSql() {
        StringBuilder sql = new StringBuilder("delete from ").append(tableName).append(" where id = ?");
        logger.info(sql.toString());
        return sql.toString();
    }

    public String getSelectOneSql() {
        StringBuilder sql = new StringBuilder("select * from ").append(tableName).append(" where id = ?");
        logger.info(sql.toString());
        return sql.toString();
    }

    public String getInsertSql(Object entity) {
        Map<String,Object> map = this.objectToMap(entity);
        map.remove("id");
        params = new Object[map.size()];
        StringBuilder stringBuiler = new StringBuilder("insert into ").append(tableName).append("(");
        for(String key : map.keySet()) {
            stringBuiler.append(key).append(",");
        }
        stringBuiler.deleteCharAt(stringBuiler.length()-1).append(") values (");
        int i = 0;
        for(String key : map.keySet()) {
            stringBuiler.append("?,");
            params[i] = map.get(key);
            i++;
        }
        stringBuiler.deleteCharAt(stringBuiler.length()-1).append(")");
        map = null;
        logger.info(stringBuiler.toString());
        return stringBuiler.toString();
    }

    public String getUpdateSql(Object entity) {
        Map<String,Object> map = this.objectToMap(entity);
        params = new Object[map.size()];
        params[params.length-1] = map.remove("id");
        StringBuilder stringBuiler = new StringBuilder("update ").append(tableName).append(" set ");
        int i = 0;
        for(String key : map.keySet()) {
            stringBuiler.append(key).append("=?,");
            params[i] = map.get(key);
            i++;
        }
        stringBuiler.deleteCharAt(stringBuiler.length()-1).append(" where id = ?");
        map = null;
        logger.info(stringBuiler.toString());
        return stringBuiler.toString();
    }

    public String getSelectList(Object entity) {
        Map<String,Object> map = this.objectToMap(entity);
        map.remove("id");
        params = new Object[map.size()];
        StringBuilder stringBuiler = new StringBuilder("select * from ").append(tableName).append(" where ");
        int i = 0;
        for(String key : map.keySet()) {
            stringBuiler.append(key).append("=? and ");
            params[i] = map.get(key);
            i++;
        }
        stringBuiler.delete(stringBuiler.length()-4, stringBuiler.length());
        map = null;
        logger.info(stringBuiler.toString());
        return stringBuiler.toString();
    }
}

SqlFactory

6.需要有一个通用的Dao接口及实现类来完成核心操作

package club.xcreeper.springboot_jdbctemplete.Core.dao;

import java.io.Serializable;
import java.util.List;

public interface CoreDao<T> {
    int insert(T t);
    int delete(Serializable id);
    int update(T t);
    T getOne(Serializable id);
    List<T> getList(T t);
}

CoreDao

package club.xcreeper.springboot_jdbctemplete.Core.dao.impl;

import club.xcreeper.springboot_jdbctemplete.Core.dao.CoreDao;
import club.xcreeper.springboot_jdbctemplete.util.SqlFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.jdbc.core.BeanPropertyRowMapper;
import org.springframework.jdbc.core.JdbcTemplate;

import java.io.Serializable;
import java.lang.reflect.ParameterizedType;
import java.util.List;

public class CoreDaoImpl<T> implements CoreDao<T> {

    private Class<T> clazz;

    private SqlFactory sqlFactory;

    @SuppressWarnings("unchecked")
    public CoreDaoImpl() {
        this.clazz =  (Class<T>)((ParameterizedType) getClass().getGenericSuperclass()).getActualTypeArguments()[0];
        sqlFactory = new SqlFactory(this.clazz);
    }

    @Autowired
    private JdbcTemplate jdbcTemplate;

    @Override
    public int insert(T t) {
        return jdbcTemplate.update(sqlFactory.getInsertSql(t),sqlFactory.params);
    }

    @Override
    public int delete(Serializable id) {
        return jdbcTemplate.update(sqlFactory.getDeleteSql(),id);
    }

    @Override
    public int update(T t) {
        return jdbcTemplate.update(sqlFactory.getUpdateSql(t),sqlFactory.params);
    }

    @Override
    public T getOne(Serializable id) {
        return jdbcTemplate.queryForObject(sqlFactory.getSelectOneSql(),new BeanPropertyRowMapper<T>(this.clazz),id);

    }

    @Override
    public List<T> getList(T t) {
        return jdbcTemplate.query(sqlFactory.getSelectList(t),new BeanPropertyRowMapper<T>(this.clazz),sqlFactory.params);
    }
}

CoreDaoImpl

7. 实体类

package club.xcreeper.springboot_jdbctemplete.entity;

import lombok.Getter;
import lombok.Setter;
import lombok.ToString;

@ToString
public class User {
    @Setter
    @Getter
    private Integer id;
    @Setter
    @Getter
    private String username;
    @Setter
    @Getter
    private String password;
}

User

package club.xcreeper.springboot_jdbctemplete.entity;

import lombok.Getter;
import lombok.Setter;
import lombok.ToString;

@ToString
public class Phone {
    @Getter@Setter
    private Integer id;
    @Getter@Setter
    private String brand;
    @Getter@Setter
    private Integer user_id;
}

Phone

8. dao接口及其实现，只需继承核心dao即可

package club.xcreeper.springboot_jdbctemplete.dao;

import club.xcreeper.springboot_jdbctemplete.Core.dao.CoreDao;
import club.xcreeper.springboot_jdbctemplete.entity.User;

public interface UserDao extends CoreDao<User> {

}

UserDao

package club.xcreeper.springboot_jdbctemplete.dao;

import club.xcreeper.springboot_jdbctemplete.Core.dao.CoreDao;
import club.xcreeper.springboot_jdbctemplete.entity.Phone;

public interface PhoneDao extends CoreDao<Phone> {

}

PhoneDao

package club.xcreeper.springboot_jdbctemplete.dao.impl;

import club.xcreeper.springboot_jdbctemplete.Core.dao.impl.CoreDaoImpl;
import club.xcreeper.springboot_jdbctemplete.dao.UserDao;
import club.xcreeper.springboot_jdbctemplete.entity.User;
import org.springframework.stereotype.Repository;

@Repository
public class UserDaoImpl extends CoreDaoImpl<User> implements UserDao {
}

UserDaoImpl

package club.xcreeper.springboot_jdbctemplete.dao.impl;

import club.xcreeper.springboot_jdbctemplete.Core.dao.impl.CoreDaoImpl;
import club.xcreeper.springboot_jdbctemplete.dao.PhoneDao;
import club.xcreeper.springboot_jdbctemplete.entity.Phone;
import org.springframework.stereotype.Repository;

@Repository
public class PhoneDaoImpl extends CoreDaoImpl<Phone> implements PhoneDao {
}

PhoneDaoImpl

9. service接口及其实现

package club.xcreeper.springboot_jdbctemplete.service;

import club.xcreeper.springboot_jdbctemplete.entity.User;

import java.util.List;

public interface UserService {
    int insert(User user);
    int delete(int id);
    int update(User user);
    User getOne(int id);
    List<User> getList(User user);
}

UserService

package club.xcreeper.springboot_jdbctemplete.service;

import club.xcreeper.springboot_jdbctemplete.entity.Phone;

import java.util.List;

public interface PhoneService {
    int insert(Phone phone);
    int delete(int id);
    int update(Phone phone);
    Phone getOne(int id);
    List<Phone> getList(Phone phone);
}

PhoneService

package club.xcreeper.springboot_jdbctemplete.service.impl;

import club.xcreeper.springboot_jdbctemplete.dao.UserDao;
import club.xcreeper.springboot_jdbctemplete.entity.User;
import club.xcreeper.springboot_jdbctemplete.service.UserService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import java.util.List;

@Service
public class UserServiceImpl implements UserService {

    @Autowired
    private UserDao userDao;

    @Override
    public int insert(User user) {
        return userDao.insert(user);
    }

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

    @Override
    public int update(User user) {
        return userDao.update(user);
    }

    @Override
    public User getOne(int id) {
        return userDao.getOne(id);
    }

    @Override
    public List<User> getList(User user) {
        return userDao.getList(user);
    }
}

UserServiceImpl

package club.xcreeper.springboot_jdbctemplete.service.impl;

import club.xcreeper.springboot_jdbctemplete.dao.PhoneDao;
import club.xcreeper.springboot_jdbctemplete.entity.Phone;
import club.xcreeper.springboot_jdbctemplete.service.PhoneService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import java.util.List;

@Service
public class PhoneServiceImpl implements PhoneService {

    @Autowired
    private PhoneDao phoneDao;

    @Override
    public int insert(Phone phone) {
        return phoneDao.insert(phone);
    }

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

    @Override
    public int update(Phone phone) {
        return phoneDao.update(phone);
    }

    @Override
    public Phone getOne(int id) {
        return phoneDao.getOne(id);
    }

    @Override
    public List<Phone> getList(Phone phone) {
        return phoneDao.getList(phone);
    }
}

PhoneServiceImpl

10. controller

package club.xcreeper.springboot_jdbctemplete.controller;

import club.xcreeper.springboot_jdbctemplete.entity.User;
import club.xcreeper.springboot_jdbctemplete.service.UserService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

import java.util.List;

@RestController
@RequestMapping("/user")
public class UserController {

    @Autowired
    private UserService userService;

    @GetMapping(value = "/{id}")
    public User getOne(@PathVariable int id) {
        return userService.getOne(id);
    }

    @GetMapping(params = {"username","password","username!=","password!="})
    public List<User> getList(User user) {
        return userService.getList(user);
    }

}

UserController

11. 启动项目，并用postman测试接口