Spring（JDBC层使用）

JDBCTemplate的使用

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导入spirng-context,spring-jdbc,spring-tx(与数据库事务有关)，mysql-connnector-java等jar包

package com.ygg.domain;

import java.io.Serializable;

/**
 * 账户实体类
 */
public class Account implements Serializable {
    private Integer id;
    private String name;
    private Float money;

    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 Float getMoney() {
        return money;
    }

    public void setMoney(Float money) {
        this.money = money;
    }

    @Override
    public String toString() {
        return "Account{" +
                "id=" + id +
                ", name='" + name + '\'' +
                ", money=" + money +
                '}';
    }
}

JDBCTemplate

package com.ygg.jdbctemplate;

import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.jdbc.datasource.DriverManagerDataSource;

public class JdbcTemplateDemo1 {
    public static void main(String[] args) {
        //1、配置数据源
        DriverManagerDataSource ds = new DriverManagerDataSource();
        ds.setDriverClassName("com.mysql.jdbc.Driver");
        ds.setUrl("jdbc:mysql://localhost:3306/mydatabase");
        ds.setUsername("root");
        ds.setPassword("root");

        //2、创建JDBCTemplate对象
        JdbcTemplate jt = new JdbcTemplate(ds);//也可以使用不带参
//        jt.setDataSource(ds);
        jt.execute("insert into acoount(name,money) values ('ccc',1000)");
    }
}

bean.xml配置方式以及CRUD

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package com.ygg.jdbctemplate;

import com.ygg.domain.Account;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.jdbc.core.RowMapper;

import java.sql.ResultSet;
import java.sql.SQLException;

/**
 * JdbcTemplate的CRUD操作
 */
public class JdbcTemplateDemo {

    public static void main(String[] args) {
        //1.获取容器
        ApplicationContext ac = new ClassPathXmlApplicationContext("bean.xml");
        //2.获取对象
        JdbcTemplate jt = ac.getBean("jdbcTemplate",JdbcTemplate.class);
        //3.执行操作
        //保存
//        jt.update("insert into account(name,money)values(?,?)","eee",3333f);
        //更新
//        jt.update("update account set name=?,money=? where id=?","test",4567,7);
        //删除
//        jt.update("delete from account where id=?",8);
        //查询所有
//        List accounts = jt.query("select * from account where money > ?",new AccountRowMapper(),1000f);
//        List accounts = jt.query("select * from account where money > ?",new BeanPropertyRowMapper(Account.class),1000f);
//        for(Account account : accounts){
//            System.out.println(account);
//        }
        //查询一个
//        List accounts = jt.query("select * from account where id = ?",new BeanPropertyRowMapper(Account.class),1);
//        System.out.println(accounts.isEmpty()?"没有内容":accounts.get(0));

        //查询返回一行一列（使用聚合函数，但不加group by子句）
        Long count = jt.queryForObject("select count(*) from account where money > ?",Long.class,1000f);//将返回一个long类型
        System.out.println(count);


    }
}

/**
 * 定义Account的封装策略
 */
class AccountRowMapper implements RowMapper{
    /**
     * 把结果集中的数据封装到Account中，然后由spring把每个Account加到集合中
     * @param rs
     * @param rowNum
     * @return
     * @throws SQLException
     */
    @Override
    public Account mapRow(ResultSet rs, int rowNum) throws SQLException {
        Account account = new Account();
        account.setId(rs.getInt("id"));
        account.setName(rs.getString("name"));
        account.setMoney(rs.getFloat("money"));
        return account;
    }
}

Dao的使用