Spring（4） Spring对JDBC的支持

Spring对DAO层提供了很好的支持。
其中对JDBC的支持有使用 JdbcTemplate，JdbcDaoSupport 和NamedParameterJdbcTemplate 三种方式。

比较常用的是JdbcTemplate类，JdbcTemplate主要提供以下五类方法：
execute方法：可以用于执行任何SQL语句，一般用于执行DDL语句；
update方法及batchUpdate方法：update方法用于执行新增、修改、删除等语句；
batchUpdate方法用于执行批处理相关语句；
query方法及queryForXXX方法：用于执行查询相关语句；
call方法：用于执行存储过程、函数相关语句。

这里就通过实例来实现JDBC对数据库的增删改查，使用的是JdbcTemplate类。
总体目录：

jar包（这里注意要加三个spring jdbc对应的包）：

数据库表（表名db_spring）:

StudentDao.java:

package com.java1234.dao;

import java.util.List;

import com.java1234.model.Student;

public interface StudentDao {

    public int addStudent(Student student);

    public int updateStudent(Student student);

    public int deleteStudent(int id);

    public List<Student> findStudents();
}

StudentDaoImpl.java:

package com.java1234.dao.impl;

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

import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.jdbc.core.RowCallbackHandler;

import com.java1234.dao.StudentDao;
import com.java1234.model.Student;

public class StudentDaoImpl implements StudentDao{

    private JdbcTemplate jdbcTemplate;

    //注入jdbc
    public void setJdbcTemplate(JdbcTemplate jdbcTemplate) {
        this.jdbcTemplate = jdbcTemplate;
    }

    @Override  //添加学生方法
    public int addStudent(Student student) {
        String sql="insert into t_student values(null,?,?)";
        //传入参数为对象数组
        Object []params=new Object[]{student.getName(),student.getAge()};
        return jdbcTemplate.update(sql,params);
    }

    @Override  //更新学生方法
    public int updateStudent(Student student) {
        String sql="update t_student set name=?,age=? where id=?";
        Object []params=new Object[]{student.getName(),student.getAge(),student.getId()};
        return jdbcTemplate.update(sql,params);
    }

    @Override   //删除学生方法
    public int deleteStudent(int id) {
        String sql="delete from t_student where id=?";
        Object []params=new Object[]{id};
        return jdbcTemplate.update(sql,params);
    }

    @Override   //实现遍历
    public List<Student> findStudents() {
        String sql="select * from t_student";
        final List<Student> studentList=new ArrayList<Student>();
        jdbcTemplate.query(sql, new RowCallbackHandler(){

            @Override
            public void processRow(ResultSet rs) throws SQLException {
                Student student=new Student();
                student.setId(rs.getInt("id"));
                student.setName(rs.getString("name"));
                student.setAge(rs.getInt("age"));
                studentList.add(student);
            }

        });
        return studentList;
    }

}

Student.java:

package com.java1234.model;

public class Student {

    private int id;
    private String name;
    private int age;

    public Student() {
        super();
    }


    public Student(String name, int age) {
        super();
        this.name = name;
        this.age = age;
    }



    public Student(int id, String name, int age) {
        super();
        this.id = id;
        this.name = name;
        this.age = age;
    }

    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 int getAge() {
        return age;
    }
    public void setAge(int age) {
        this.age = age;
    }

    @Override
    public String toString() {
        return "Student [id=" + id + ", name=" + name + ", age=" + age + "]";
    }



}

StudentService.java:

package com.java1234.service;

import java.util.List;

import com.java1234.model.Student;

public interface StudentService {

    public int addStudent(Student student);

    public int updateStudent(Student student);

    public int deleteStudent(int id);

    public List<Student> findStudents();
}

StudentServiceImpl.java:

package com.java1234.service.impl;

import java.util.List;

import com.java1234.dao.StudentDao;
import com.java1234.model.Student;
import com.java1234.service.StudentService;

public class StudentServiceImpl implements StudentService{

    private StudentDao studentDao;

    public void setStudentDao(StudentDao studentDao) {
        this.studentDao = studentDao;
    }

    @Override
    public int addStudent(Student student) {
        return studentDao.addStudent(student);
    }

    @Override
    public int updateStudent(Student student) {
        return studentDao.updateStudent(student);
    }

    @Override
    public int deleteStudent(int id) {
        return studentDao.deleteStudent(id);
    }

    @Override
    public List<Student> findStudents() {
        return studentDao.findStudents();
    }



}

T.java:

package com.java1234.test;

import java.util.List;
import org.junit.Before;
import org.junit.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import com.java1234.model.Student;
import com.java1234.service.StudentService;

public class T {

    private ApplicationContext ac;

    @Before
    public void setUp() throws Exception {
        ac=new ClassPathXmlApplicationContext("beans.xml");
    }

    @Test
    public void addStudent() {
        StudentService studentService=(StudentService)ac.getBean("studentService");
        int addNums=studentService.addStudent(new Student("小王", 1));
        if(addNums==1){
            System.out.println("添加成功");
        }
    }

    @Test
    public void updateStudent() {
        StudentService studentService=(StudentService)ac.getBean("studentService");
        int updateNums=studentService.updateStudent(new Student(8,"小王的爸爸", 30));
        if(updateNums==1){
            System.out.println("更新成功");
        }
    }

    @Test
    public void deleteStudent() {
        StudentService studentService=(StudentService)ac.getBean("studentService");
        int deleteNums=studentService.deleteStudent(8);
        if(deleteNums==1){
            System.out.println("删除成功");
        }
    }

    @Test
    public void findStudents() {
        StudentService studentService=(StudentService)ac.getBean("studentService");
        List<Student> studentList=studentService.findStudents();
        for(Student student:studentList){
            System.out.println(student);
        }
    }

}

beans.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"
    xsi:schemaLocation="http://www.springframework.org/schema/beans
        http://www.springframework.org/schema/beans/spring-beans.xsd
        http://www.springframework.org/schema/aop
        http://www.springframework.org/schema/aop/spring-aop.xsd
        http://www.springframework.org/schema/context
        http://www.springframework.org/schema/context/spring-context.xsd">

    <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/db_spring" />
        <property
            name="username"
            value="root" />
        <property
            name="password"
            value="123" />
    </bean>

    <bean id="jdbcTemplate" class="org.springframework.jdbc.core.jdbcTemplate">
          <property name="dataSource" ref="dataSource"></property>
          <property name="newsource" ref="newsource"></property>
    </bean>

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

    <!-- 注入dao层，并引入jdbcTempemplate -->
    <bean id="studentDao" class="com.java1234.dao.impl.StudentDaoImpl">
        <property name="jdbcTemplate" ref="jdbcTemplate"></property>
    </bean> 

    <!-- 注入服务层，并引入stdentDao -->
    <bean id="studentService" class="com.java1234.service.impl.StudentServiceImpl">
        <property name="studentDao" ref="studentDao"></property>
    </bean> 

</beans>

最后测试结果，大家可以自己试一下。