[Spring+SpringMVC+Mybatis]框架学习笔记(三):Spring实现JDBC
上一章:[Spring+SpringMVC+Mybatis]框架学习笔记(二):Spring-IOC-DI
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第3章 Spring实现JDBC
利用springJdbcTemplate实现一个表的简单的增删改查。
事先建表:
CREATE DATABASE STUDENT;
USE STUDENT;
CREATE TABLE STUDENT(
ID INT PRIMARY KEY AUTO_INCREMENT,
NAME VARCHAR(20) NOT NULL,
AGE INT NOT NULL,
SEX TINYINT(1) UNSIGNED DEFAULT 0 NOT NULL
)AUTO_INCREMENT = 100000;
INSERT INTO STUDENT(NAME,AGE,SEX) VALUES("STEVEN",31,1);
INSERT INTO STUDENT(NAME,AGE) VALUES("LUCY",28);
注入数据库连接的四要素(数据库类型、地址、用户名、密码):
- 引入数据库驱动包
mysql-connector-java-5.1.39-bin.jar
ojdbc5.jar - 引入spring-jdbc的jar包
spring-jdbc-4.2.1.RELEASE.jar
spring-tx-4.2.1.RELEASE.jar(跟事务相关)
3.1 实现方式1:配置文件方式
3.1.1 实体类
package com.steven.spring.sysmgr.entity;
import java.io.Serializable;
/**
* 实体类
* @author chenyang
*
*/
public class Student implements Serializable{
/**
*
*/
private static final long serialVersionUID = -3587920774423955014L;
public Student(){
}
private int id;
private String name;
private int age;
private int sex;
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;
}
public int getSex() {
return sex;
}
public void setSex(int sex) {
this.sex = sex;
}
}
3.1.2 DAO层的接口和实现类
1)DAO接口:
package com.steven.spring.sysmgr.dao;
import java.util.List;
import java.util.Map;
import com.steven.spring.sysmgr.entity.Student;
public interface IStudentDao {
public boolean addStudent(Student student);
public boolean delStudent(Integer studentId);
public boolean updateStudent(Student student);
public List<Map<String, Object>> getStudentMap();
public List<Student> getStudentList();
}
2)DAO接口的实现:
package com.steven.spring.sysmgr.dao.impl;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.List;
import java.util.Map;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.jdbc.core.RowMapper;
import com.steven.spring.sysmgr.dao.IStudentDao;
import com.steven.spring.sysmgr.entity.Student;
public class StudentDao implements IStudentDao{
private JdbcTemplate jdbcTemplate;
public void setJdbcTemplate(JdbcTemplate jdbcTemplate) {
this.jdbcTemplate = jdbcTemplate;
}
@Override
public boolean addStudent(Student student) {
boolean flag = false;
String addSql = "INSERT INTO STUDENT(NAME,AGE,SEX) VALUES(?,?,?)";
int rows = this.jdbcTemplate.update(addSql, student.getName(), student.getAge(), student.getSex());
if(rows > 0){
flag = true;
}
return flag;
}
@Override
public boolean delStudent(Integer studentId) {
boolean flag = false;
String delSql = "DELETE FROM STUDENT WHERE ID = ?";
int rows = this.jdbcTemplate.update(delSql, studentId);
if(rows > 0){
flag = true;
}
return flag;
}
@Override
public boolean updateStudent(Student student) {
boolean flag = false;
String updateSql = "UPDATE STUDENT SET NAME=?, AGE=?, SEX=? WHERE ID=? ";
int rows = this.jdbcTemplate.update(updateSql, student.getName(), student.getAge(), student.getSex(), student.getId());
if(rows > 0){
flag = true;
}
return flag;
}
@Override
public List<Map<String, Object>> getStudentMap() {
return this.jdbcTemplate.queryForList("SELECT ID,NAME,AGE,SEX FROM STUDENT");
}
@Override
public List<Student> getStudentList() {
String querySql = "SELECT ID, NAME, AGE, SEX FROM STUDENT";
//第1种方式:用接口的匿名内部类来实现,优点:可以根据需求做二次改造
/*return this.jdbcTemplate.query(querySql, new RowMapper<Student>(){
@Override
public Student mapRow(ResultSet rs, int rowNum) throws SQLException {
Student student = new Student();
student.setId(rs.getInt("ID"));
student.setName(rs.getString("NAME"));
student.setAge(rs.getInt("AGE"));
student.setSex(rs.getInt("SEX"));
return student;
}
});*/
//第2种方式:直接将行结果集映射到实体类中,优点:简便
return this.jdbcTemplate.query(querySql, new BeanPropertyRowMapper<Student>(Student.class));
}
}
3.1.3 服务层的接口和实现类
1)服务类接口:
package com.steven.spring.sysmgr.service;
import java.util.List;
import java.util.Map;
import com.steven.spring.sysmgr.entity.Student;
public interface IStudentService {
public boolean addStudent(Student student);
public boolean delStudent(Integer studentId);
public boolean updateStudent(Student student);
public List<Map<String, Object>> getStudentMap();
public List<Student> getStudentList();
}
2)服务类接口的实现,它依赖于IStudentDao:
package com.steven.spring.sysmgr.service.impl;
import java.util.List;
import java.util.Map;
import com.steven.spring.sysmgr.dao.IStudentDao;
import com.steven.spring.sysmgr.entity.Student;
import com.steven.spring.sysmgr.service.IStudentService;
public class StudentService implements IStudentService{
private IStudentDao studentDao;
public void setStudentDao(IStudentDao studentDao) {
this.studentDao = studentDao;
}
@Override
public boolean addStudent(Student student) {
// TODO Auto-generated method stub
return this.studentDao.addStudent(student);
}
@Override
public boolean delStudent(Integer studentId) {
// TODO Auto-generated method stub
return this.studentDao.delStudent(studentId);
}
@Override
public boolean updateStudent(Student student) {
// TODO Auto-generated method stub
return this.studentDao.updateStudent(student);
}
@Override
public List<Map<String, Object>> getStudentMap() {
// TODO Auto-generated method stub
return this.studentDao.getStudentMap();
}
@Override
public List<Student> getStudentList() {
// TODO Auto-generated method stub
return this.studentDao.getStudentList();
}
}
3.1.4 spring-IOC的配置文件
spring-IOC的配置文件applicationContext.xml:利用SpringIOC实现服务类和DAO类的依赖
<?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">
<!-- 注册服务类,并描述依赖关系 -->
<bean id="studentService" class="com.steven.spring.sysmgr.service.impl.StudentService">
<property name="studentDao" ref="studentDao"/>
</bean>
<!-- 注册DAO类 -->
<bean id="studentDao" class="com.steven.spring.sysmgr.dao.impl.StudentDao">
<property name="jdbcTemplate" ref="jdbcTemplate"/>
</bean>
<!-- 注册springJdbc查询模板,模板依赖于数据源 -->
<bean id="jdbcTemplate" class="org.springframework.jdbc.core.JdbcTemplate">
<property name="dataSource" ref="dataSource"/>
</bean>
<!-- 注册spring自带的管理数据库连接的数据源 -->
<bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
<property name="driverClassName" value="com.mysql.jdbc.Driver"/>
<property name="url" value="jdbc:mysql://127.0.0.1:3306/student"/>
<property name="username" value="root"/>
<property name="password" value="123"/>
</bean>
</beans>
3.1.5 测试类
package com.steven.spring.sysmgr.test;
import org.junit.Before;
import org.junit.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import com.steven.spring.sysmgr.entity.Student;
import com.steven.spring.sysmgr.service.IStudentService;
public class SpringJdbcTest {
private ApplicationContext ac;
@Before
public void init(){
ac = new ClassPathXmlApplicationContext("applicationContext.xml");
}
//模拟增加功能
@Test
public void testAddStudent(){
IStudentService studentService = (IStudentService) ac.getBean("studentService");
Student student = new Student();
student.setName("Jacky");
student.setAge(35);
student.setSex(1);
System.out.println(studentService.addStudent(student));
}
//模拟删除功能
@Test
public void testDelStudent(){
IStudentService studentService = (IStudentService) ac.getBean("studentService");
int delStudentId = 100000;
System.out.println(studentService.delStudent(delStudentId));
}
//模拟更改功能
@Test
public void testUpdateStudent(){
IStudentService studentService = (IStudentService) ac.getBean("studentService");
Student student = new Student();
student.setId(100001);
student.setName("Lily");
student.setAge(26);
student.setSex(0);
System.out.println(studentService.updateStudent(student));
}
//模拟查询功能,返回List<Student>
@Test
public void testGetStudentList(){
IStudentService studentService = (IStudentService) ac.getBean("studentService");
System.out.println(studentService.getStudentList());
}
//模拟查询功能,返回List<Map<String, object>>
@Test
public void testGetStudentMap(){
IStudentService studentService = (IStudentService) ac.getBean("studentService");
System.out.println(studentService.getStudentMap());
}
}
3.2 实现方式2:注解方式
1、在服务层接口实现类(@Service(...))和Dao层接口实现类(@Repository(...))中分别加入注解表示符,并声明依赖关系(@Autowired)
1)DAO的实现类
package com.steven.spring.sysmgr.dao.impl;
import java.util.List;
import java.util.Map;
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 com.steven.spring.sysmgr.dao.IStudentDao;
import com.steven.spring.sysmgr.entity.Student;
@Repository("studentDao")
public class StudentDao implements IStudentDao{
@Autowired
private JdbcTemplate jdbcTemplate;
public void setJdbcTemplate(JdbcTemplate jdbcTemplate) {
this.jdbcTemplate = jdbcTemplate;
}
@Override
public boolean addStudent(Student student) {
boolean flag = false;
String addSql = "INSERT INTO STUDENT(NAME,AGE,SEX) VALUES(?,?,?)";
int rows = this.jdbcTemplate.update(addSql, student.getName(), student.getAge(), student.getSex());
if(rows > 0){
flag = true;
}
return flag;
}
@Override
public boolean delStudent(Integer studentId) {
boolean flag = false;
String delSql = "DELETE FROM STUDENT WHERE ID = ?";
int rows = this.jdbcTemplate.update(delSql, studentId);
if(rows > 0){
flag = true;
}
return flag;
}
@Override
public boolean updateStudent(Student student) {
boolean flag = false;
String updateSql = "UPDATE STUDENT SET NAME=?, AGE=?, SEX=? WHERE ID=? ";
int rows = this.jdbcTemplate.update(updateSql, student.getName(), student.getAge(), student.getSex(), student.getId());
if(rows > 0){
flag = true;
}
return flag;
}
@Override
public List<Map<String, Object>> getStudentMap() {
return this.jdbcTemplate.queryForList("SELECT ID,NAME,AGE,SEX FROM STUDENT");
}
@Override
public List<Student> getStudentList() {
String querySql = "SELECT ID, NAME, AGE, SEX FROM STUDENT";
//第1种方式:用接口的匿名内部类来实现,优点:可以根据需求做二次改造
/*return this.jdbcTemplate.query(querySql, new RowMapper<Student>(){
@Override
public Student mapRow(ResultSet rs, int rowNum) throws SQLException {
Student student = new Student();
student.setId(rs.getInt("ID"));
student.setName(rs.getString("NAME"));
student.setAge(rs.getInt("AGE"));
student.setSex(rs.getInt("SEX"));
return student;
}
});*/
//第2种方式:直接将行结果集映射到实体类中,优点:简便
return this.jdbcTemplate.query(querySql, new BeanPropertyRowMapper<Student>(Student.class));
}
}
2)服务层的实现类
package com.steven.spring.sysmgr.service.impl;
import java.util.List;
import java.util.Map;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import com.steven.spring.sysmgr.dao.IStudentDao;
import com.steven.spring.sysmgr.entity.Student;
import com.steven.spring.sysmgr.service.IStudentService;
@Service("studentService")
public class StudentService implements IStudentService{
@Autowired
private IStudentDao studentDao;
public void setStudentDao(IStudentDao studentDao) {
this.studentDao = studentDao;
}
@Override
public boolean addStudent(Student student) {
// TODO Auto-generated method stub
return this.studentDao.addStudent(student);
}
@Override
public boolean delStudent(Integer studentId) {
// TODO Auto-generated method stub
return this.studentDao.delStudent(studentId);
}
@Override
public boolean updateStudent(Student student) {
// TODO Auto-generated method stub
return this.studentDao.updateStudent(student);
}
@Override
public List<Map<String, Object>> getStudentMap() {
// TODO Auto-generated method stub
return this.studentDao.getStudentMap();
}
@Override
public List<Student> getStudentList() {
// TODO Auto-generated method stub
return this.studentDao.getStudentList();
}
}
2、在配置文件中进行加入约束和扫描包
<?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"
xsi:schemaLocation="
http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context.xsd">
<!-- 扫描包 -->
<context:component-scan base-package="com.steven.spring.sysmgr"></context:component-scan>
<!-- 注册springJdbc查询模板,模板依赖于数据源 -->
<bean id="jdbcTemplate" class="org.springframework.jdbc.core.JdbcTemplate">
<property name="dataSource" ref="dataSource"/>
</bean>
<!-- 注册spring自带的管理数据库连接的数据源 -->
<bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
<property name="driverClassName" value="com.mysql.jdbc.Driver"/>
<property name="url" value="jdbc:mysql://127.0.0.1:3306/student"/>
<property name="username" value="root"/>
<property name="password" value="123"/>
</bean>
</beans>
3.3 实现方式3:Dao实现类继承JdbcDaoSupport
在Dao接口实现里,不用引入JdbcTemplate的接口,而是继承JdbcDaoSupport。因为JdbcDaoSupport类引入了JdbcTemlate。
使用这种方式时,可以不用注入jdbcTemplate,即dao实现类直接依赖于dataSource。因为在类JdbcDaoSupport中会实例化JdbcTemplate。
<?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">
<!-- 注册服务类,并描述依赖关系 -->
<bean id="studentService" class="com.steven.spring.sysmgr.service.impl.StudentService">
<property name="studentDao" ref="studentDao"/>
</bean>
<!-- 注册DAO类: 当Dao实现类继承了JdbcDaoSupport,可以直接注入dataSource-->
<bean id="studentDao" class="com.steven.spring.sysmgr.dao.impl.StudentDao">
<property name="dataSource" ref="dataSource"/>
</bean>
<!-- 注册spring自带的管理数据库连接的数据源 -->
<bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
<property name="driverClassName" value="com.mysql.jdbc.Driver"/>
<property name="url" value="jdbc:mysql://127.0.0.1:3306/student"/>
<property name="username" value="root"/>
<property name="password" value="123"/>
</bean>
</beans>
3.4 实现方式4:利用properties配置文件方式
1、在src根目录下新建一个配置文件jdbc.properties
jdbc.driver=com.mysql.jdbc.Driver
jdbc.url=jdbc:mysql://127.0.0.1:3306/student
jdbc.user=root
jdbc.password=123
2、让spring加载配置文件
1)加载properties配置文件内容
方式1:
<bean class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">
<property name="location" value="classpath:jdbc.properties"/>
</bean>
方式2:
首先在xml配置文件中引入context头文件标签。
<context:property-placeholder location="classpath:jdbc.properties"/>
2)将dataSource的bean标签更改为:
<!-- 注册spring自带的管理数据库连接的数据源 -->
<bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
<property name="driverClassName" value="${jdbc.driver}"/>
<property name="url" value="${jdbc.url}"/>
<property name="username" value="${jdbc.user}"/>
<property name="password" value="${jdbc.password}"/>
</bean>
3.5 实现方式5:c3p0数据源连接池
1)引入c3p0数据连接池的jar包:c3p0-0.9.0.jar
2)xml配置文件数据源连接部分改为(注意不同点):
<!-- 注册c3p0数据源连接池 -->
<bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
<property name="driverClass" value="${jdbc.driver}"/>
<property name="jdbcUrl" value="${jdbc.url}"/>
<property name="user" value="${jdbc.user}"/>
<property name="password" value="${jdbc.password}"/>
</bean>
3.6 实现方式6:dbcp数据源连接池
1)引入dbcp数据源连接池(Apache公司)需要的jar包
commons-dbcp-1.4.jar
commons-pool-1.6.jar
2)xml配置文件数据源连接部分改为(注意不同点):
<!-- 注册dbcp数据源连接池 -->
<bean id="dataSource" class="org.apache.commons.dbcp.BasicDataSource">
<property name="driverClassName" value="${jdbc.driver}"/>
<property name="url" value="${jdbc.url}"/>
<property name="username" value="${jdbc.user}"/>
<property name="password" value="${jdbc.password}"/>
</bean>
上一章:[Spring+SpringMVC+Mybatis]框架学习笔记(二):Spring-IOC-DI
下一章:[Spring+SpringMVC+Mybatis]框架学习笔记(四):Spring实现AOP
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