spring框架综合案例：

首先是保存实体类信息的entity层：

entity层：

UserInfo类

package edu.youzg.entity;

public class UserInfo {
    private int id;
    private String name;
    private String password;
    private float balance;

    public UserInfo() {
    }

    public UserInfo(String name) {
        this.name = name;
    }

    public UserInfo(String name, String password) {
        this.password = password;
        this.name = name;
    }

    public UserInfo(int id, String name, int balance) {
        this.id = id;
        this.name = name;
        this.balance = balance;
    }

    public UserInfo(int id, String name, String password, int balance) {
        this.id = id;
        this.name = name;
        this.password = password;
        this.balance = balance;
    }

    public int getId() {
        return id;
    }

    public UserInfo setId(int id) {
        this.id = id;
        return this;
    }

    public String getName() {
        return name;
    }

    public UserInfo setName(String name) {
        this.name = name;
        return this;
    }

    public String getPassword() {
        return password;
    }

    public UserInfo setPassword(String password) {
        this.password = password;
        return this;
    }

    public float getBalance() {
        return balance;
    }

    public UserInfo setBalance(float balance) {
        this.balance = balance;
        return this;
    }

    @Override
    public String toString() {
        StringBuffer str = new StringBuffer();
        str.append("账户[").append(name).append("]目前余额为：[").append(balance).append("]元");
        return str.toString();
    }

}

接下来是联系数据库的dao层：

dao层：

IUserDao接口

package edu.youzg.dao;

import edu.youzg.entity.UserInfo;

public interface IUserDao {
    void saveUser(String name, String password);
    void updateInfo(String name, String password, int id);
    void updateBalance(int id, float deltaMoney);
    UserInfo queryByLoginName(String name);
    UserInfo queryByID(int id);
    void deleteUser(String name, int id);
}

UserDao类

package edu.youzg.dao;

import edu.youzg.entity.UserInfo;

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;

/**
 * 用户的数据库访问类
 */
@Repository
public class UserDao implements IUserDao {

    @Autowired
    private JdbcTemplate jt;

    @Override
    public void saveUser(String name, String password) {
        String sql = "insert into account(name, password, balance) values(?, ?, ?)";
        jt.update(sql, name, password, 0);
    }

    @Override
    public void updateInfo(String name, String password, int id) {
        String sql = "update account set name=?, password=? where id=?";
        jt.update(sql, name, password, id);
    }

    @Override
    public void updateBalance(int id, float deltaMoney) {
        String sql = "update account set balance=balance+? where id=?";
        jt.update(sql, deltaMoney, id);
    }

    @Override
    public UserInfo queryByLoginName(String name) {
        String sql = "select * from account where name=? ";
        List<UserInfo> list = jt.query(sql, new BeanPropertyRowMapper<UserInfo>(UserInfo.class), name);
        if (list!=null && list.size()>=1){
            return list.get(0);
        }
        return null;
    }


    @Override
    public UserInfo queryByID(int id) {
        String sql="select * from account where id=?";
        //返回一条数据
        // return jt.queryForObject(sql,new BeanPropertyRowMapper<UserInfo>(UserInfo.class),name);
        List<UserInfo> list = jt.query(sql, new BeanPropertyRowMapper<UserInfo>(UserInfo.class), id);
        if(list!=null && list.size()>=1){
            return list.get(0);
        }
        return null;
    }

    @Override
    public void deleteUser(String name, int id) {
        String sql = "delete from account where name=? and id=?";
        jt.update(sql, name, id);
    }

}

然后是提供对外功能的service层：

service层：

IUserService接口：

package edu.youzg.service;

import edu.youzg.entity.UserInfo;

/**
 * @Author: Youzg
 * @CreateTime: 2020-05-05 10:06
 * @Description:带你深究Java的本质！
 */
public interface IUserService {
    // 用户功能
    UserInfo register(UserInfo user);
    UserInfo login(UserInfo user);
    void saveMoney(UserInfo user, float money);
    boolean withdrawMonney(UserInfo user, float money);
    float queryBalance(UserInfo user);
    void transfer(UserInfo fromUser, UserInfo toUser, float money);

    // 管理员功能
    void deleteUser(UserInfo user);
}

UserService类

package edu.youzg.service;

import edu.youzg.dao.IUserDao;
import edu.youzg.entity.UserInfo;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;

/**
 * 用户业务逻辑
 */
@Transactional	//添加 事务控制
@Service("userService")
public class UserService implements IUserService {

    //数据库访问对象
    @Autowired
    private IUserDao dao;

    @Override
    public UserInfo register(UserInfo user) {
        String name = user.getName();
        String pass = user.getPassword();
        UserInfo userInfo = dao.queryByLoginName(name);
        if (null!=userInfo) {
            System.out.println("用户名已存在！");
            return new UserInfo().setId(-1);
        }
        dao.saveUser(name, pass);

        // 获取id，以便上层处理
        UserInfo res = dao.queryByLoginName(name);

        return res;
    }

    @Override
    public UserInfo login(UserInfo user) {
        UserInfo userInfo = dao.queryByLoginName(user.getName());
        if (userInfo.getId() > 0) {
            return userInfo;
        }
        return null;
    }

    @Override
    public void saveMoney(UserInfo user, float money) {
        UserInfo userInfo = dao.queryByLoginName(user.getName());
        if (null==userInfo || userInfo.getId() <= 0) {
            return;
        }
        dao.updateBalance(userInfo.getId(), money);
    }

    @Override
    public boolean withdrawMonney(UserInfo user, float money) {
        UserInfo userInfo = dao.queryByLoginName(user.getName());
        if (null == userInfo || userInfo.getBalance() < money) {
            return false;
        }

        dao.updateBalance(userInfo.getId(), -money);
        return true;
    }

    @Override
    public float queryBalance(UserInfo user) {
        UserInfo userInfo = dao.queryByLoginName(user.getName());
        if (null == userInfo) {
            return -1;
        }
        return userInfo.getBalance();
    }

    @Override
    public void deleteUser(UserInfo user) {
        UserInfo userInfo = dao.queryByLoginName(user.getName());
        if (null == userInfo) {
            return;
        }
        dao.deleteUser(userInfo.getName(), userInfo.getId());
    }

    // 转账业务逻辑
    @Override
    public void transfer(UserInfo fromUser, UserInfo toUser, float money)  {
        UserInfo from = dao.queryByLoginName(fromUser.getName());
        UserInfo to = dao.queryByLoginName(toUser.getName());
        if (null==from || null==to) {
            return;
        }
        //账号-钱
        dao.updateBalance(from.getId(), -money);

        //账号+钱
        dao.updateBalance(to.getId(), money);
    }

}

接下来是运用了aop技术、用于日志管理的切面层：

aspect层：

LoggerAspect

package edu.youzg.aspect;

import org.aspectj.lang.ProceedingJoinPoint;
import org.aspectj.lang.annotation.Around;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.Pointcut;
import org.springframework.stereotype.Component;

@Component
@Aspect
public class LoggerAspect {

    @Pointcut("execution(* edu.youzg.service.*.*(..))")
    public void pointCut(){}

    @Around("pointCut()")
    public Object around(ProceedingJoinPoint pjp) throws Throwable {
        Object result = null;
        long stime = System.currentTimeMillis();
        try {
            result = pjp.proceed(pjp.getArgs());//执行目标业务逻辑
        } finally {
            long etime = System.currentTimeMillis();
            long time = etime - stime;    //方法执行耗时时间
            String mname = pjp.getSignature().getName();
            String cname = pjp.getTarget().getClass().getName();
            //输出什么类，什么方法，什么时间，什么参数被执行了
            String msg = String.format("类名：" + cname + "方法名：" + mname + "执行耗时(毫秒)：" + time);
            System.out.println(msg);
        }
        return result;
    }

}

最后是用于配置spring、开启各种注解扫描的配置层：

config层：

SpringConfig类

package edu.youzg.config;

import com.alibaba.druid.pool.DruidDataSource;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.context.annotation.*;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.jdbc.datasource.DataSourceTransactionManager;
import org.springframework.transaction.annotation.EnableTransactionManagement;

import javax.sql.DataSource;

/**
 * 使用java类配置spring
 */

@Configuration//声明这是spring配置类
@ComponentScan("edu.youzg")//扫描包
@EnableAspectJAutoProxy//开启aop注解支持
@PropertySource("youzgDB.properties")//读取配置文件
@EnableTransactionManagement//开启事务解析器
public class SpringConfig {
    @Value("${db.username}")
    private String userName;
    @Value("${db.password}")
    private String passWord;
    @Value("${db.url}")
    private String url;
    @Value("${db.driverClassName}")
    private String driverClassName;

    //  创建数据源
    @Bean
    public DruidDataSource getDruidDataSource(){
        DruidDataSource ds=new DruidDataSource();
        ds.setUsername(userName);
        ds.setPassword(passWord);
        ds.setUrl(url);
        ds.setDriverClassName(driverClassName);
        //更多数据库连接池调优参数 根据官方文档设置即可
        return ds;
    }
    //创建jdbc模板类对象
    @Bean
    public JdbcTemplate getJdbcTemplate(DataSource ds){
        return new JdbcTemplate(ds);
    }

    //创建事务管理器
    @Bean
    public DataSourceTransactionManager getDataSourceTransactionManager(DataSource ds){
        return new DataSourceTransactionManager(ds);
    }

}

配置文件：

db.driverClassName=com.mysql.jdbc.Driver
db.url=jdbc:mysql://localhost:3306/dbstudy?serverTimezone=UTC&characterEncoding=utf-8 
db.username=root
db.password=123456

最后，本人来给出测试类：

测试类：

YouzgTest类

package edu.youzg.test;

import edu.youzg.config.SpringConfig;
import edu.youzg.dao.TransferDao;
import edu.youzg.entity.UserInfo;
import edu.youzg.service.IUserService;
import edu.youzg.service.UserService;
import org.springframework.context.ApplicationContext;
import org.springframework.context.annotation.AnnotationConfigApplicationContext;

/**
 * @Author: Youzg
 * @CreateTime: 2020-05-03 08:50
 * @Description:带你深究Java的本质！
 */
public class YouzgTest {

    public static void main(String[] args) {
        ApplicationContext context = new AnnotationConfigApplicationContext(SpringConfig.class);
        IUserService service = context.getBean("userService", IUserService.class);
        UserInfo newUser = new UserInfo("youzg666", "123456");
        service.register(newUser);
        service.saveMoney(newUser, 100);
        service.transfer(newUser, new UserInfo("youzg"), 20);
    }

}

接下来，本人来展示下运行结果：

运行结果：

【运行前】初始账户数据

【运行后】控制台日志

【运行后】最终账户数据