#Spring JdbcTemplate - 增删改查(CRUD) @FDDLC

项目结构：

 

pom.xml的内容：

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>org.example</groupId>
    <artifactId>P033_JdbcTemplate_CRUD</artifactId>
    <version>1.0-SNAPSHOT</version>

    <dependencies>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>8.0.16</version>
        </dependency>

        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-jdbc</artifactId>
            <version>5.1.8.RELEASE</version>
        </dependency>

        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-context</artifactId>
            <version>5.1.8.RELEASE</version>
        </dependency>
    </dependencies>

</project>

 

MySQL数据库：

database：test        port：3306        table：id_name

 

bean.xml的内容:

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd">
    <bean class="org.springframework.jdbc.datasource.DriverManagerDataSource" id="dataSource">
        <property name="driverClassName" value="com.mysql.cj.jdbc.Driver"></property>
        <property name="url" value="jdbc:mysql://localhost:3306/test?characterEncoding=UTF8&amp;serverTimezone=Asia/Shanghai"></property>
        <property name="username" value="root"></property>
        <property name="password" value="123456"></property>
    </bean>

    <bean class="org.springframework.jdbc.core.JdbcTemplate" id="template">
        <property name="dataSource" ref="dataSource"></property>
    </bean>
</beans>

 

Account.java的内容：

package cn.liuxingchang;

import java.io.Serializable;

public class Account implements Serializable {
    private Integer id;
    private String name;
    private Double 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 Double getMoney() {
        return money;
    }

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

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

 

Main.java的内容：

package cn.liuxingchang;

import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import org.springframework.jdbc.core.BeanPropertyRowMapper;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.jdbc.core.RowMapper;

import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.List;

public class Main {

    public static void main(String[] args) {
        //ApplicationContext context = new ClassPathXmlApplicationContext("bean.xml");
        ApplicationContext context = new ClassPathXmlApplicationContext("bean.xml");
        JdbcTemplate template = context.getBean("template", JdbcTemplate.class);
        /*
        //1、update：插入、修改、删除
        template.update("insert into account(id, name, money) values(?, ?, ?)", 5, "Zhou", 500);
        template.update("update account set money = ? where id = ?", 456, 4);
        template.update("delete from account where id = ?", 3);
        */

        //2、query：查询多行、查询一行
        /*
        List<Account> accounts = template.query("select * from account",
                new BeanPropertyRowMapper<Account>(Account.class));
        for (Account account: accounts) {
            System.out.println(account);
        }
         */
        //上面和下面功能一样，推荐使用上面！
        List<Account> accounts = template.query("select * from account",
                new AccountRowMapper());
        for(Account account: accounts) {
            System.out.println(account);
        }
        List<Account> account = template.query("select * from account where id = ?",
                new BeanPropertyRowMapper<Account>(Account.class), 1);
        System.out.println("查询一行：" + account.get(0));

        //3、queryForObject：查询一行一列，如：count
        Integer count = template.queryForObject("select count(*) from account", Integer.class);
        System.out.println(count);
    }
}

//这里定义一个类，用于测试自定义RowMapper。其实完全没必要！
class AccountRowMapper implements RowMapper<Account> {
    public Account mapRow(ResultSet resultSet, int i) throws SQLException {
        Account account = new Account();
        account.setId(resultSet.getInt("id"));
        account.setName(resultSet.getString("name"));
        account.setMoney(resultSet.getDouble("money"));
        return account;
    }
}