Spring JdbcTemplate的使用秘籍

首先要引入：

<dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-jdbc</artifactId>
      <version>5.2.3.RELEASE</version>
    </dependency>
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-tx</artifactId>
      <version>5.2.3.RELEASE</version>
    </dependency>
    <dependency>
      <groupId>mysql</groupId>
      <artifactId>mysql-connector-java</artifactId>
      <version>8.0.17</version>
    </dependency>

再配置一下​​applicationContext.xml​​

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:aop="http://www.springframework.org/schema/aop"
       xmlns:context="http://www.springframework.org/schema/context"
       xmlns:tx="http://www.springframework.org/schema/tx"
       xsi:schemaLocation="http://www.springframework.org/schema/beans
       http://www.springframework.org/schema/beans/spring-beans.xsd
       http://www.springframework.org/schema/context
       https://www.springframework.org/schema/context/spring-context.xsd
       http://www.springframework.org/schema/aop
       https://www.springframework.org/schema/aop/spring-aop.xsd
       http://www.springframework.org/schema/tx
       http://www.springframework.org/schema/tx/spring-tx.xsd">

     <!--配置mysql-->
     <bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
          <property name="driverClassName" value="com.mysql.jdbc.Driver"/>
          <property name="url" value="jdbc:mysql://localhost:3306/spring?serverTimezone=UTC&useUnicode=true&characterEncoding=utf-8"/>
          <property name="username" value="root"/>
          <property name="password" value="你自己的数据库密码"/>
     </bean>
     <!--配置jdbc templete-->
     <bean id="jdbctemplate" class="org.springframework.jdbc.core.JdbcTemplate">
     <property name="dataSource" ref="dataSource"/>
     </bean>


</beans>

定义一个学生类：Student,数据库中有Student表，进行测试

package com.ibuyi.free.spring.jdbc;

public class Student {
    private int id;
    private String name;
    private String sex;
    private String born;

    public int getId() {
        return id;
    }

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

    public String getName() {
        return name;
    }

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

    public String getSex() {
        return sex;
    }

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

    public String getBorn() {
        return born;
    }

    public void setBorn(String born) {
        this.born = born;
    }

    @Override
    public String toString() {
        return "{" +id+' '+name+' '+sex+' '+born+
                "}";
    }
}

package com.ibuyi.free.spring.jdbc;

import org.junit.Test;
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;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;

public class JdbcTest {
    private JdbcTemplate jdbcTemplate;
    {
        ApplicationContext context=new ClassPathXmlApplicationContext("spring.xml");
        jdbcTemplate= (JdbcTemplate) context.getBean("jdbctemplate");
    }

    public void test(){
      //首先创建一张表
        String sql="create table test(id int,name varchar(20))";
        jdbcTemplate.execute(sql);

    }
    @Test
    public void test1(){
        //查询一个数据
        String sql = "select count(*) from student";
        int count=jdbcTemplate.queryForObject(sql,Integer.class);
        System.out.println(count);
    }


    public void test2(){
        //更新一条数据
        String sql="update student set sex=? where id=?";
        int count = jdbcTemplate.update(sql,"女",1);
        System.out.println(count);
    }

    @Test
    public void test3(){
        //插入一条数据
        String sql = "insert into student(name,sex,born) values(?,?,?)";
        int count =jdbcTemplate.update(sql,"zhang","男","1999-07-16");
        System.out.println(count);
    }


    public void test4(){
        String []sql={
        //批量插入
        "insert into student(name,sex,born) values('zhang','女','1999-07-16')",
        "insert into student(name,sex,born) values('bei','女','1999-07-16')",
        "insert into student(name,sex,born) values('di','女','1999-07-16')"
       };
        int[] count =jdbcTemplate.batchUpdate(sql);
        System.out.println(count);
    }
    @Test
    public void test5(){
        //执行同构sql
        String sql="insert into course(name,score) values(?,?)";
        List<Object[]> list=new ArrayList<>();
        list.add(new Object[]{"Java",80});
        list.add(new Object[]{"MySQL",100});
        list.add(new Object[]{"JavaEE",90});

        int[] count=jdbcTemplate.batchUpdate(sql,list);
        System.out.println(count[0]);

    }

    @Test
    public void test6(){
        //执行查询
        String sql = "select name from student where sex=?";
        List<String> list = jdbcTemplate.queryForList(sql,String.class,"女");
        System.out.println(list);

    }

    public void test7(){
        //查询一条复杂对象
        String sql = "select * from student where id=?";
        Map<String,Object> map=jdbcTemplate.queryForMap(sql,1);
        System.out.println(map);

    }

    @Test
    public void test8(){
        //查询多条负责对象
        String sql = "select * from student where sex=?";
        List<Map<String,Object>> map=jdbcTemplate.queryForList(sql,"女");
        System.out.println(map);

    }
    @Test
    public void test9(){
        //查询一个复杂对象，封装为实体对象
        String sql = "select * from student where id=?";
        Student students= (Student) jdbcTemplate.queryForObject(sql,new StudentRowMaper(),1);
        System.out.println(students);


    }

    @Test
    public void test10(){
        //查询多个复杂对象，封装为实体对象
        String sql = "select * from student where sex=?";
        List<Student> students = jdbcTemplate.query(sql,new StudentRowMaper(),"女");
        for(Student student:students){
            System.out.println(student);
        }



    }

    private class StudentRowMaper implements RowMapper{

        @Override
        public Object mapRow(ResultSet resultSet, int i) throws SQLException {
            Student student=new Student();
            student.setName(resultSet.getString("name"));
            student.setId(resultSet.getInt("Id"));
            student.setSex(resultSet.getString("sex"));
            student.setBorn(resultSet.getString("born"));
            return student;
        }
    }


}