spring+JdbcTemplate简单使用(一)

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目录

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1. 环境配置

1. maven（项目管理）
2. idea（编译器）
3. jdk1.8（Java环境）
4. MySQL5.6（MySQL数据库）

2. 创建项目

1. 在 idea 中创建普通的 maven 项目

2. 新建 resources 目录用来存放配置文件
   

   3. 配置 pom.xml(导入 jar 包)

<properties>
        <aspectj.version>1.8.1</aspectj.version>
        <aopalliance.version>1.0</aopalliance.version>
        <!--spring版本-->
        <spring.version>5.0.8.RELEASE</spring.version>
    </properties>

    <dependencies>

        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-core</artifactId>
            <version>${spring.version}</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-context</artifactId>
            <version>${spring.version}</version>
        </dependency>

        <!--spring-jdbc-->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-jdbc</artifactId>
            <version>${spring.version}</version>
        </dependency>

        <!--测试 -->
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.10</version>
        </dependency>

        <!--spring 面向切面start-->
        <dependency>
            <groupId>org.aspectj</groupId>
            <artifactId>aspectjrt</artifactId>
            <version>${aspectj.version}</version>
        </dependency>
        <dependency>
            <groupId>org.aspectj</groupId>
            <artifactId>aspectjweaver</artifactId>
            <version>${aspectj.version}</version>
        </dependency>
        <dependency>
            <groupId>aopalliance</groupId>
            <artifactId>aopalliance</artifactId>
            <version>${aopalliance.version}</version>
        </dependency>
        <!--spring 面向切面end-->

        <!--MySQL 驱动包-->
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>5.1.46</version>
        </dependency>
        <!--c3p0连接池-->
        <dependency>
            <groupId>c3p0</groupId>
            <artifactId>c3p0</artifactId>
            <version>0.9.1.2</version>
        </dependency>
    </dependencies>

4. 配置文件（resources 目录下）

1. db.properties

#用户名
jdbc.user=root
#登录密码
jdbc.password=123456
#驱动
jdbc.driverClass=com.mysql.jdbc.Driver
#连接路径
jdbc.jdbcUrl=jdbc:mysql:///test

#初始化连接数量
jdbc.initPoolSize=5
#最大连接数
jdbc.maxPoolSize=10

db.properties 是数据库配置文件

1. 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: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/tx http://www.springframework.org/schema/tx/spring-tx-4.0.xsd
        http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.0.xsd">

    <!--自动扫描包，此处 com.tuck.jdbc 改成自己实际项目包路径-->
    <!--扫描 com.ordust 包及子包中所有的组件类-->
    <context:component-scan base-package="com.ordust.jdbc"/>

    <!--导入资源文件-->
    <context:property-placeholder location="classpath:db.properties"/>

    <!--配置 c3p0 数据源-->
    <bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
        <property name="user" value="${jdbc.user}"/>
        <property name="password" value="${jdbc.password}"/>
        <property name="jdbcUrl" value="${jdbc.jdbcUrl}"/>
        <property name="driverClass" value="${jdbc.driverClass}"/>

        <property name="initialPoolSize" value="${jdbc.initPoolSize}"/>
        <property name="maxPoolSize" value="${jdbc.maxPoolSize}"/>
    </bean>

    <!--配置 JdbcTemplate -->
    <bean id="jdbcTemplate" class="org.springframework.jdbc.core.JdbcTemplate">
        <property name="dataSource" ref="dataSource"/>
    </bean>
</beans>

applicationContext.xml 是 spring 的配置文件

5. 创建测试数据库

DROP TABLE IF EXISTS `student`;
CREATE TABLE `student` (
  `id` int(11) NOT NULL AUTO_INCREMENT COMMENT ‘学号‘,
  `name` varchar(50) NOT NULL COMMENT ‘姓名‘,
  `age` int(11) NOT NULL COMMENT ‘年龄‘,
  `teacher_id` int(11) NOT NULL COMMENT ‘老师工号‘,
  PRIMARY KEY (`id`),
  KEY `teacher_id` (`teacher_id`),
  CONSTRAINT `student_ibfk_1` FOREIGN KEY (`teacher_id`) REFERENCES `teacher` (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;


DROP TABLE IF EXISTS `teacher`;
CREATE TABLE `teacher` (
  `id` int(11) NOT NULL AUTO_INCREMENT COMMENT ‘工号‘,
  `name` varchar(50) NOT NULL COMMENT ‘姓名‘,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

student 表与 teacher 表中主键为学号，为演示方便，设置成自增

插入数据

insert into `teacher` (`id`, `name`) values(‘1‘,‘张三‘);
insert into `teacher` (`id`, `name`) values(‘2‘,‘李四‘);
insert into `teacher` (`id`, `name`) values(‘3‘,‘王五‘);

insert into `student` (`id`, `name`, `age`, `teacher_id`) values(‘1‘,‘AA‘,‘10‘,‘1‘);
insert into `student` (`id`, `name`, `age`, `teacher_id`) values(‘2‘,‘BB‘,‘11‘,‘1‘);
insert into `student` (`id`, `name`, `age`, `teacher_id`) values(‘3‘,‘CC‘,‘12‘,‘2‘);

6. 新建实体类

1. Teacher.java

public class Teacher {
    private int id;//老师工号
    private String name;//老师姓名
    
    /*省略对应的 setter getter 和 toString 方法*/
}

1. Student.java

public class Student {
    private int id;//学生学号
    private String studentName;//学生姓名
    private int age;//年龄
    private Teacher teacher;
    /*省略对应的 setter getter 和 toString 方法*/
}

7. 持久层（dao）

import com.ordust.entity.Student;
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;

@Repository //标识为持久层组件
public class StudentDao {

    @Autowired //自动装配jdbcTemplate
    private JdbcTemplate jdbcTemplate;

    /**
     * 添加、修改、删除一个student对象
     * 此处只实现 修改
     *
     * @param student 学生实体类
     * @return 返回操作结果
     */
    public int testUpdate(Student student) {
        String sql = "update student set name = ?, age = ? where id = ?";
        return jdbcTemplate.update(sql, student.getStudentName(), student.getAge(), student.getId());
    }

    /**
     * 执行批量更新：批量的 INSERT, UPDATE, DELETE
     *
     * @param batchArgs Object[] 的 list 集合
     * @return 返回操作结果
     */
    public int[] testBatchUpdate(List<Object[]> batchArgs) {
        String sql = "INSERT INTO student VALUES(null,?,?,?)";
        return jdbcTemplate.batchUpdate(sql, batchArgs);
    }

    /**
     * 从数据库中读取一条记录，得到对应的一个对象
     * 注意使用的方法为 queryForObject(String sql, RowMapper<T> rowMapper, @Nullable Object... args)
     *
     * @param id 需要查找的id
     * @return 返回student对象
     */
    public Student testQueryForObject(int id) {
        /**
         * 1、使用 sql 中的列的别名完成列名和类的属性名的映射 如下面sql语句：name studentName
         * 2、JdbcTemplate 不支持级联属性，此处 teacher.id 值为空
         */
        String sql = "SELECT id, name studentName , age, teacher_id AS `teacher.id` FROM student WHERE id=?";
        BeanPropertyRowMapper<Student> rowMapper = new BeanPropertyRowMapper<Student>(Student.class);
        return jdbcTemplate.queryForObject(sql, rowMapper, id);
    }

    /**
     * 得到实体类集合
     * 注意调用的不是 queryForList 方法
     *
     * @param id 参数
     * @return student 集合
     */
    public List<Student> testQueryForList(Integer id) {
        String sql = "SELECT id, name studentName, age FROM student WHERE id > ?";
        BeanPropertyRowMapper<Student> rowMapper = new BeanPropertyRowMapper<Student>(Student.class);
        return jdbcTemplate.query(sql, rowMapper, id);
    }

    /**
     * 获取单个列的值，或做统计查询
     * 使用 queryForObject(String sql, Class<T> requiredType) 方法
     */
    public Integer testQueryForObject2() {
        String sql = "select  count(*) from student";
        return jdbcTemplate.queryForObject(sql, Integer.class);
    }

}

8. 测试（test）

import com.ordust.dao.StudentDao;
import com.ordust.entity.Student;
import org.junit.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import org.springframework.jdbc.core.JdbcTemplate;

import java.util.ArrayList;
import java.util.List;

/**
 * 测试类，用来测试 StudentDao 类
 */
public class Demo {
    private ApplicationContext context = new ClassPathXmlApplicationContext("applicationContext.xml");
    private StudentDao studentDao = context.getBean(StudentDao.class);

    /**
     * 执行 INSERT, UPDATE, DELETE
     */
    @Test
    public void testUpdate() {
        Student student = new Student();
        student.setStudentName("哈哈哈");
        student.setAge(22);
        student.setId(3);
        int i = studentDao.testUpdate(student);
        System.out.println(i);
    }

    @Test
    public void testBatchUpdate() {
        List<Object[]> batchArgs = new ArrayList<Object[]>();

        batchArgs.add(new Object[]{"鼠大王", 22, 1});
        batchArgs.add(new Object[]{"东侧", 22, 2});
        batchArgs.add(new Object[]{"嘻嘻", 22, 3});

        studentDao.testBatchUpdate(batchArgs);
    }

    @Test
    public void testQueryForObject() {
        int id = 1;
        Student student = studentDao.testQueryForObject(id);
        System.out.println(student);
    }

    @Test
    public void testQueryForList() {
        List<Student> students = studentDao.testQueryForList(1);
        for (Student student : students) {
            System.out.println(student);
        }
    }

    @Test
    public void testQueryForObject2() {
        Integer integer = studentDao.testQueryForObject2();
        System.out.println(integer);
    }
}

9. 下载源码

springjdbc-test

spring+JdbcTemplate简单使用(一)

标签：drop   contex   port   ima   char   自动扫描   blog   读取   src   

原文地址：https://www.cnblogs.com/ordust/p/10010544.html