pox.xml  导入包

<dependency>
    <groupId>junit</groupId>  <!--junit单元测试-->
    <artifactId>junit</artifactId>
    <version>4.11</version>
    <scope>test</scope>
</dependency>
<dependency> <!--junit单元测试-->
    <groupId>junit</groupId>
    <artifactId>junit</artifactId>
    <version>4.11</version>
    <scope>compile</scope>
</dependency>
<dependency>   <!--mybatis 依赖-->
    <groupId>org.mybatis</groupId>
    <artifactId>mybatis</artifactId>
    <version>3.4.6</version>
</dependency>
<dependency>  <!--mysql 依赖-->
    <groupId>mysql</groupId>
    <artifactId>mysql-connector-java</artifactId>
    <version>5.1.48</version>
</dependency>
<dependency> <!--log 日志-->
    <groupId>org.apache.logging.log4j</groupId>
    <artifactId>log4j-core</artifactId>
    <version>2.12.1</version>
</dependency>
<dependency> <!--log 日志-->
    <groupId>org.apache.logging.log4j</groupId>
    <artifactId>log4j-api</artifactId>
    <version>2.12.1</version>
</dependency>
<dependency>  <!-- druid 阿里提供的mysql连接池 -->
    <groupId>com.alibaba</groupId>
    <artifactId>druid</artifactId>
    <version>1.1.21</version>
</dependency>
<dependency>  <!--commons-logging  jdbc template 需要的包-->
    <groupId>commons-logging</groupId>
    <artifactId>commons-logging</artifactId>
    <version>1.2</version>
</dependency>
<dependency>  <!--commons-logging  jdbc template 需要的包-->
    <groupId>org.springframework</groupId>
    <artifactId>spring-beans</artifactId>
    <version>5.2.5.RELEASE</version>
</dependency>
<dependency>  <!--spring-core  jdbc template 需要的包-->
    <groupId>org.springframework</groupId>
    <artifactId>spring-core</artifactId>
    <version>5.2.5.RELEASE</version>
</dependency>
<dependency>  <!--spring-jdbc  jdbc template 需要的包-->
    <groupId>org.springframework</groupId>
    <artifactId>spring-jdbc</artifactId>
    <version>5.2.5.RELEASE</version>
</dependency>
<dependency>  <!--spring-tx  jdbc template 需要的包-->
    <groupId>org.springframework</groupId>
    <artifactId>spring-tx</artifactId>
    <version>5.2.5.RELEASE</version>
</dependency>

创建resources文件夹 放置配置文件

resources-->druid.properties  数据库配置文件

driverClassName=com.mysql.jdbc.Driver
url=jdbc:mysql://10.133.3.26:3306/mybatis_test?useUnicode=true&characterEncoding=utf8&useSSL=false
username=root
password=root
# 初始化连接数量
initialSize=5
# 最大连接数
maxActive=10
# 最大等待时间
maxWait=3000

resources-->log4j2.xml  日志配置文件

<?xml version="1.0" encoding="UTF-8"?>
<Configuration status="WARN">
    <Appenders>
        <Console name="Console" target="SYSTEM_OUT">
            <PatternLayout pattern="%d{YYYY-MM-dd HH:mm:ss} [%t] %-5p %c{1}:%L - %msg%n"/>
        </Console>

        <RollingFile name="RollingFile" filename="log/test.log"
                     filepattern="${logPath}/%d{YYYYMMddHHmmss}-fargo.log">
            <PatternLayout pattern="%d{YYYY-MM-dd HH:mm:ss} [%t] %-5p %c{1}:%L - %msg%n"/>
            <Policies>
                <SizeBasedTriggeringPolicy size="10 MB"/>
            </Policies>
            <DefaultRolloverStrategy max="20"/>
        </RollingFile>

    </Appenders>
    <Loggers>
        <Root level="info">
            <AppenderRef ref="Console"/>
            <AppenderRef ref="RollingFile"/>
        </Root>
    </Loggers>
</Configuration>

创建java-->utils文件夹

java-->utils-->JDBCUtils  jdbc普通封装

package mysql.java.utils;

import com.alibaba.druid.pool.DruidDataSourceFactory;

import javax.sql.DataSource;
import java.io.IOException;
import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.Properties;


// Druid连接池的工具类
public class JDBCUtils {

    //1.定义成员变量 DataSource
    private static DataSource ds;

    static {
        try {
            //1.加载配置文件
            Properties pro = new Properties();
            pro.load(JDBCUtils.class.getClassLoader().getResourceAsStream("druid.properties"));
            //2.获取DataSource
            ds = DruidDataSourceFactory.createDataSource(pro);
        } catch (IOException e) {
            e.printStackTrace();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }


    // 获取连接
    public static Connection getConnection() throws SQLException {
        return ds.getConnection();
    }

   // 释放资源
    public static void close(Statement stmt, Connection conn) {
        close(null, stmt, conn);
    }

    public static void close(ResultSet rs, Statement stmt, Connection conn) {
        if (rs != null) {
            try {
                rs.close();
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }


        if (stmt != null) {
            try {
                stmt.close();
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }

        if (conn != null) {
            try {
                conn.close();//归还连接
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }
    }

    // 获取连接池方法
    public static DataSource getDataSource() {
        return ds;
    }

}

domain --> Emp.java   object对象

package mysql.domain;

import java.util.Date;

public class Emp {
    private Integer id;
    private String username;
    private Date birthday;
    private String sex;
    private String address;

    @Override
    public String toString() {
        return "Emp{" +
                "id=" + id +
                ", username='" + username + '\'' +
                ", birthday=" + birthday +
                ", sex='" + sex + '\'' +
                ", address='" + address + '\'' +
                '}';
    }

    public void setId(Integer id) {
        this.id = id;
    }

    public void setUsername(String username) {
        this.username = username;
    }

    public void setBirthday(Date birthday) {
        this.birthday = birthday;
    }

    public void setSex(String sex) {
        this.sex = sex;
    }

    public void setAddress(String address) {
        this.address = address;
    }

    public Integer getId() {
        return id;
    }

    public String getUsername() {
        return username;
    }

    public Date getBirthday() {
        return birthday;
    }

    public String getSex() {
        return sex;
    }

    public String getAddress() {
        return address;
    }

    public Emp(Integer id, String username, Date birthday, String sex, String address) {
        this.id = id;
        this.username = username;
        this.birthday = birthday;
        this.sex = sex;
        this.address = address;
    }

    public Emp() {
    }
}

jdbctemplate --> JdbcTmpalateDome.java   数据库操作

package mysql.jdbctemplate;

import mysql.domain.Emp;
import mysql.java.utils.JDBCUtils;
import org.junit.Before;
import org.junit.Test;
import org.springframework.jdbc.core.BeanPropertyRowMapper;
import org.springframework.jdbc.core.JdbcTemplate;

import java.text.DateFormat;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.List;
import java.util.Map;

public class JdbcTemplateDome01 {
    private JdbcTemplate template;

    @Before
    public void init() {
        template = new JdbcTemplate(JDBCUtils.getDataSource());   // 获取JDBCTemplate对象
    }

    @Test
    public void selectSql() {    // 查询数据
        String sql = "UPDATE user set address=? WHERE id=?";
        int count = template.update(sql, "杭州", "49");
        System.out.println(count);
    }

    @Test
    public void insterSql() {  // 插入一条数据
        String sql = "INSERT INTO user(username, birthday, sex, address) values(?, ?, ?, ?)";
        String date = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss").format(new Date());
        int count = template.update(sql, "yoyo", date, "男", "上海");
        System.out.println(count);
    }

    @Test
    public void deleteSql() {  // 删除一条数据
        String sql = "DELETE from user WHERE id=?";
        int count = template.update(sql, 50);
        System.out.println(count);
    }

    /**
     * queryForMap:查询结果将结果集封装为map集合,将列名作为key,将值作为value 将这条记录封装为一个map集合
     * 这个方法查询的结果集长度只能是1
     */
    @Test
    public void selectMap() {  // 查询一条数据 封装成map集合
        String sql = "select * from user where id=?";
        Map<String, Object> map = template.queryForMap(sql, 49);
        System.out.println(map);
    }

    /**
     * queryForList:查询结果将结果集封装为list集合
     * 将每一条记录封装为一个Map集合,再将Map集合装载到List集合中
     */
    @Test
    public void selectListMap() { // 查询所有数据封装为list
        String sql = "select * from user";
        List<Map<String, Object>> mapList = template.queryForList(sql);
        for (Map<String, Object> map : mapList) {
            System.out.println(map);
        }
    }

    /**
     * query:查询结果,将结果封装为JavaBean对象
     * uery的参数:RowMapper
     * 一般我们使用BeanPropertyRowMapper实现类。可以完成数据到JavaBean的自动封装
     * new BeanPropertyRowMapper<类型>(类型.class)
     */
    @Test
    public void selectListEnp() {  // 查询所有记录,将其封装为Emp对象的List集合
        String sql = "select * from user";
        List<Emp> list = template.query(sql, new BeanPropertyRowMapper<Emp>(Emp.class));
        for (Emp emp : list) {
            System.out.println(emp);
        }
    }

    /**
     * queryForObject:查询结果,将结果封装为对象
     * 一般用于聚合函数的查询
     */
    @Test
    public void selectObject() {  // 查询总记录数
        String sql = "select count(id) from user";
        Long total = template.queryForObject(sql, Long.class);
        System.out.println(total);
    }

}