【Spring六】JDBC编程之XML配置
jdbc编程最主要的就是要引入数据源，常见的有dbcp数据源，c3p0数据源等。
几个重要的类：
JdbcTemplate，里面提供了dao的方法，需要提供数据源给他！
JdbcDaoSupport
RowMapper
说明：
无论采用什么样的方法必须把dataSource注入到JdbcTemplate里
1、继承JdbcDaoSupport(该类有JdbcTemplate)
2、继承JdbcTemplate
3、引入JdbcTemplate
无论采用什么样的方法必须把dataSource注入到JdbcTemplate里
1、继承JdbcDaoSupport(该类有JdbcTemplate)
2、继承JdbcTemplate
3、引入JdbcTemplate
1.xml配置：
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<
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-2.5.xsd"
>
<
bean
class= "org.springframework.beans.factory.config.PropertyPlaceholderConfigurer" >
<property name= "locations">
<value> classpath:jdbc.propertiesvalue >
property>
bean
>
<
bean
id="dataSource" destroy-method="close"
class= "org.apache.commons.dbcp.BasicDataSource" >
<property name= "driverClassName" value="${jdbc.driverClassName}" />
<property name= "url" value ="${jdbc.url}" />
<property name= "username" value="${jdbc.username}" />
<property name= "password" value="${jdbc.password}" />
bean
>
<
bean
id="classesDao" class="cn.itheima03.spring.jdbc.ClassesDaoImpl" >
<property name= "dataSource">
<ref bean= "dataSource"/>
property>
bean
>
<
bean
id="jdbcTemplate" class="org.springframework.jdbc.core.JdbcTemplate" >
<constructor-arg index= "0" ref="dataSource" >constructor-arg>
bean
>
<
bean
id="classesDao2" class="cn.itheima03.spring.jdbc.ClassesDaoImpl2" >
<property name= "jdbcTemplate">
<ref bean= "jdbcTemplate"/>
property>
bean
>
<
bean
id="classesDao3" class="cn.itheima03.spring.jdbc.ClassesDaoImpl3" >
<constructor-arg index= "0" ref="dataSource" >constructor-arg>
bean
>
<
bean
id="itheimaTemplate" class="cn.itheima03.spring.itheima03db.ItHeimaTemplate" >
<constructor-arg index= "0" ref="dataSource" >constructor-arg>
bean
>
<
bean
id="classesDao4" class="cn.itheima03.spring.itheima03db.ClassesDaoImpl4" >
<constructor-arg index= "0" ref="dataSource" >constructor-arg>
bean
>
beans
>
==============================================
位于src目录下的配置文件:
jdbc.properties
jdbc.driverClassName=
com.mysql.jdbc.Driver
jdbc.url=
jdbc\:mysql \://localhost\:3306/hibernate_itheima03
jdbc.username=
root
jdbc.password=
root
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2.dao测试
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/*
* 方式一：继承JdbcDaoSupport,需要使用数据源，在配置文件中应该配置。
*/
public
class ClassesDaoImpl extends JdbcDaoSupport implements ClassesDao{
public
void saveClasses() {
this.getJdbcTemplate().execute("insert into classes(cname,description) values('a','a')");
}
@Override
public
List
return this .getJdbcTemplate().query("select * from classes", new ClassesRowMapper()) ;
}
}
===================================================
/**
* 方式二:引入JdbcTemplate
*/
public
class ClassesDaoImpl2 implements ClassesDao{
private
JdbcTemplate jdbcTemplate;
public
JdbcTemplate getJdbcTemplate() {
return jdbcTemplate ;
}
public
void setJdbcTemplate(JdbcTemplate jdbcTemplate) {
this.jdbcTemplate = jdbcTemplate;
}
public
void saveClasses() {
this.jdbcTemplate .execute("insert into classes(cname,description) values('a','a')");
}
@Override
public
List
return null ;
}
}
===================================================
/**
* 方式三：继承JdbcTemplate,写一个以DataSource作为参数的构造函数。
*/
public
class ClassesDaoImpl3 extends JdbcTemplate implements ClassesDao{
public
ClassesDaoImpl3(DataSource dataSource){
super(dataSource);
}
public
void saveClasses() {
this.execute("insert into classes(cname,description) values('a','a')");
}
@Override
public
List
return null;
}
}
===================================================
/**
* 方式四：自定义模板。
*
* 在spring内部完成是面向接口编程
* 在spring的配置文件中,通过set方法或者构造器，给接口注入实现的类
*
*/
public
class ItHeimaTemplate {
private
DataSource dataSource;
public
DataSource getDataSource() {
return dataSource ;
}
public
void setDataSource(DataSource dataSource) {
this.dataSource = dataSource;
}
public
ItHeimaTemplate(){}
public
ItHeimaTemplate(DataSource dataSource){
this.dataSource = dataSource;
}
/**
* 实现插入数据
*/
public
void insert(String sql){
try {
Connection conn =
this.dataSource .getConnection();
Statement statement = conn.createStatement();
statement.executeUpdate(sql);
}
catch (Exception e) {
}
}
}
---------------------------------------------------
public
class ClassesDaoImpl4 extends ItHeimaTemplate{
public
ClassesDaoImpl4(DataSource dataSource){
super(dataSource);
}
public
void insert(){
this.insert("insert into classes(cname,description) values('a','a')");
}
}
===================================================
public
class DataSourceTest {
@Test
public
void testDataSource(){
ApplicationContext context =
new ClassPathXmlApplicationContext("cn/itheima03/spring/jdbc/applicationContext.xml" );
DataSource dataSource = (DataSource)context.getBean(
"dataSource"
);
System.
out.println(dataSource);
}
}
===================================================
/**
* 查询时，需要写一个类实现RowMapper
*/
public
class ClassesRowMapper implements RowMapper{
@Override
public
Object mapRow(ResultSet rs, int rowNum) throws SQLException {
Classes classes =
new Classes();
classes.setCid(rs.getLong(
"cid"));
classes.setCname(rs.getString(
"cname"));
classes.setDescription(rs.getString(
"description"));
return classes;
}
}
===================================================
public
class ClassesDaoTest {
@Test
public
void testSaveClasses(){
ApplicationContext context =
new ClassPathXmlApplicationContext("cn/itheima03/spring/jdbc/applicationContext.xml" );
ClassesDao classesDao = (ClassesDao)context.getBean(
"classesDao3"
);
classesDao.saveClasses();
}
@Test
public
void testSaveClasses4(){
ApplicationContext context =
new ClassPathXmlApplicationContext("cn/itheima03/spring/jdbc/applicationContext.xml" );
ClassesDaoImpl4 classesDao = (ClassesDaoImpl4)context.getBean(
"classesDao4"
);
classesDao.insert();
}
/**
* 测试查询
*/
@Test
public
void testGetClasses(){
ApplicationContext context =
new ClassPathXmlApplicationContext("cn/itheima03/spring/jdbc/applicationContext.xml" );
ClassesDao classesDao = (ClassesDao)context.getBean(
"classesDao"
);
System.
out.println(classesDao.getClasses().size());
}
}
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