1. 示例代码
CustomerDao.java ，dao接口
public interface CustomerDao {
public void insertCustomer(Customer c);
public void updateCustomer(Customer c);
public List<Customer> findCustomerByName(String name);
}
CustomerDaoImpl.java 接口实现
/**
* CustomerDaoImpl
*/
public class CustomerDaoImpl implements CustomerDao {
private JdbcTemplate jt ;
public void setJt(JdbcTemplate jt) {
this.jt = jt;
}
public List<Customer> findCustomerByName(String name) {
String sql="select id,name,age from customers where name = ?";
return jt.query(sql, new Object[]{name}, new RowMapper(){
public Object mapRow(ResultSet rs, int rowNum) throws SQLException {
Customer c = new Customer();
c.setId(rs.getInt("id"));
c.setName(rs.getString("name"));
c.setAge(rs.getInt("age"));
return c;
}});
}
/**
* 插入
*/
public void insertCustomer(Customer c) {
String sql = "insert into customers(name,age) values(?,?)";
jt.update(sql, new Object[]{c.getName(),c.getAge()});
}
public void updateCustomer(Customer c) {
String sql = "update customers set name = ?,age = ? where id = ?";
jt.update(sql,new Object[]{c.getName(),c.getAge(),c.getId()});
}
}
jdbc.properties 分散配置
jdbc.driverclass=com.mysql.jdbc.Driver jdbc.url=jdbc:mysql://localhost:3306/spring jdbc.username=root jdbc.password=root c3p0.pool.size.max=10 c3p0.pool.size.min=2 c3p0.pool.size.ini=3 c3p0.pool.size.increment=2
dao.xml 配置文件
<?xml version="1.0"?>
<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-2.5.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context-2.5.xsd ">
<!-- 指定分散配置的文件的位置 -->
<context:property-placeholder location="classpath:cn/itcast/spring/dao/jdbc.properties"/>
<!-- 配置c3p0数据源 -->
<bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
<property name="driverClass" value="${jdbc.driverclass}" />
<property name="jdbcUrl" value="${jdbc.url}" />
<property name="user" value="${jdbc.username}" />
<property name="password" value="${jdbc.password}" />
<property name="maxPoolSize" value="${c3p0.pool.size.max}" />
<property name="minPoolSize" value="${c3p0.pool.size.min}" />
<property name="initialPoolSize" value="${c3p0.pool.size.ini}" />
<property name="acquireIncrement" value="${c3p0.pool.size.increment}" />
</bean>
<bean id="jt" class="org.springframework.jdbc.core.JdbcTemplate">
<property name="dataSource" ref="dataSource" />
</bean>
<!-- customerDao -->
<bean id="customerDao" class="cn.itcast.spring.dao.CustomerDaoImpl">
<property name="jt" ref="jt" />
</bean>
<!-- *************************** daoSupport **************************** -->
<bean id="customerDaoSuport" class="cn.itcast.spring.dao.CustomerDaoSuportImpl">
<property name="dataSource" ref="dataSource" />
</bean>
</beans>
App.java 测试代码
public class App {
public static void main(String[] args) throws SQLException {
ApplicationContext ac = new ClassPathXmlApplicationContext(
"cn/itcast/spring/dao/dao.xml");
CustomerDao dao = (CustomerDao) ac.getBean("customerDao");
Customer c = new Customer();
c.setName("tom");
c.setAge(23);
dao.insertCustomer(c);
//
c = new Customer();
c.setId(1);
c.setName("jerry");
c.setAge(23);
dao.updateCustomer(c);
dao.findCustomerByName("tom");
}
}
CustomerDaoSuportImpl.java 另外一种配置方法： 省略模板的配置
/**
* CustomerDaoImpl,省略模板的配置
*/
public class CustomerDaoSuportImpl extends JdbcDaoSupport implements CustomerDao {
public List<Customer> findCustomerByName(String name) {
String sql="select id,name,age from customers where name = ?";
return getJdbcTemplate().query(sql, new Object[]{name}, new RowMapper(){
public Object mapRow(ResultSet rs, int rowNum) throws SQLException {
Customer c = new Customer();
c.setId(rs.getInt("id"));
c.setName(rs.getString("name"));
c.setAge(rs.getInt("age"));
return c;
}});
}
/**
* 插入
*/
public void insertCustomer(Customer c) {
String sql = "insert into customers(name,age) values(?,?)";
getJdbcTemplate().update(sql, new Object[]{c.getName(),c.getAge()});
}
public void updateCustomer(Customer c) {
String sql = "update customers set name = ?,age = ? where id = ?";
getJdbcTemplate().update(sql,new Object[]{c.getName(),c.getAge(),c.getId()});
}
}
AppDaoSupport.java 省略模板配置 测试代码
public class AppDaoSupport {
public static void main(String[] args) throws SQLException {
ApplicationContext ac = new ClassPathXmlApplicationContext(
"cn/itcast/spring/dao/dao.xml");
CustomerDao dao = (CustomerDao) ac.getBean("customerDaoSuport");
Customer c = new Customer();
c.setName("tom");
c.setAge(23);
dao.insertCustomer(c);
}
}