Spring + JdbcTemplate + JdbcDaoSupport examples
In Spring JDBC development, you can use JdbcTemplate
and JdbcDaoSupport
classes to simplify the overall database operation processes.
In this tutorial, we will reuse the last Spring + JDBC example, to see the different between a before (No JdbcTemplate
support) and after (With JdbcTemplate
support) example.
1. Example Without JdbcTemplate
Witout JdbcTemplate
, you have to create many redundant codes (create connection , close connection , handle exception) in all the DAO database operation methods – insert, update and delete. It just not efficient, ugly, error prone and tedious.
private DataSource dataSource;
public void setDataSource(DataSource dataSource) {
this.dataSource = dataSource;
}
public void insert(Customer customer){
String sql = "INSERT INTO CUSTOMER " +
"(CUST_ID, NAME, AGE) VALUES (?, ?, ?)";
Connection conn = null;
try {
conn = dataSource.getConnection();
PreparedStatement ps = conn.prepareStatement(sql);
ps.setInt(1, customer.getCustId());
ps.setString(2, customer.getName());
ps.setInt(3, customer.getAge());
ps.executeUpdate();
ps.close();
} catch (SQLException e) {
throw new RuntimeException(e);
} finally {
if (conn != null) {
try {
conn.close();
} catch (SQLException e) {}
}
}
}
2. Example With JdbcTemplate
With JdbcTemplate
, you save a lot of typing on the redundant codes, becuase JdbcTemplate
will handle it automatically.
private DataSource dataSource;
private JdbcTemplate jdbcTemplate;
public void setDataSource(DataSource dataSource) {
this.dataSource = dataSource;
}
public void insert(Customer customer){
String sql = "INSERT INTO CUSTOMER " +
"(CUST_ID, NAME, AGE) VALUES (?, ?, ?)";
jdbcTemplate = new JdbcTemplate(dataSource);
jdbcTemplate.update(sql, new Object[] { customer.getCustId(),
customer.getName(),customer.getAge()
});
}
See the different?
3. Example With JdbcDaoSupport
By extended the JdbcDaoSupport
, set the datasource
and JdbcTemplate
in your class is no longer required, you just need to inject the correct datasource
into JdbcCustomerDAO
. And you can get the JdbcTemplate
by using a getJdbcTemplate()
method.
public class JdbcCustomerDAO extends JdbcDaoSupport implements CustomerDAO
{
//no need to set datasource here
public void insert(Customer customer){
String sql = "INSERT INTO CUSTOMER " +
"(CUST_ID, NAME, AGE) VALUES (?, ?, ?)";
getJdbcTemplate().update(sql, new Object[] { customer.getCustId(),
customer.getName(),customer.getAge()
});
}
<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 id="dataSource"
class="org.springframework.jdbc.datasource.DriverManagerDataSource">
<property name="driverClassName" value="com.mysql.jdbc.Driver" />
<property name="url" value="jdbc:mysql://localhost:3306/mkyongjava" />
<property name="username" value="root" />
<property name="password" value="password" />
</bean>
</beans>
<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 id="customerDAO" class="com.mkyong.customer.dao.impl.JdbcCustomerDAO">
<property name="dataSource" ref="dataSource" />
</bean>
</beans>
Note
In Spring JDBC development, it’s always recommended to useJdbcTemplate
andJdbcDaoSupport
, instead of coding JDBC code yourself.