【Spring六】JDBC编程之XML配置

来源：互联网发布：珍宝岛自卫反击战知乎编辑：程序博客网时间：2024/06/05 08:31

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

1.xml配置：

<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" >

<value> classpath:jdbc.properties</value >

</property>

</bean >

<bean id="dataSource" destroy-method="close"

class= "org.apache.commons.dbcp.BasicDataSource" >

</bean >

</property>

</bean >

<constructor-arg index= "0" ref="dataSource" ></constructor-arg>

</bean >

</property>

</bean >

<constructor-arg index= "0" ref="dataSource" ></constructor-arg>

</bean >

<constructor-arg index= "0" ref="dataSource" ></constructor-arg>

</bean >

<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

2.dao测试

* 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<Classes> getClasses() {

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<Classes> getClasses() {

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<Classes> getClasses() {

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());

}

0 0