Spring Object/XML mapping example

In this tutorial, we will extend last Maven + Spring hello world example by adding JDBC support, to use Spring + JDBC to insert a record into a customer table.

1. Customer table

In this example, we are using MySQL database.

CREATE TABLE `customer` (
  `CUST_ID` int(10) unsigned NOT NULL AUTO_INCREMENT,
  `NAME` varchar(100) NOT NULL,
  `AGE` int(10) unsigned NOT NULL,
  PRIMARY KEY (`CUST_ID`)
) ENGINE=InnoDB AUTO_INCREMENT=2 DEFAULT CHARSET=utf8;

2. Project Dependency

Add Spring and MySQL dependencies in Maven pom.xml file.

File : pom.xml

<project xmlns="http://maven.apache.org/POM/4.0.0" 
  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 
  http://maven.apache.org/maven-v4_0_0.xsd">
  <modelVersion>4.0.0</modelVersion>
  <groupId>com.mkyong.common</groupId>
  <artifactId>SpringExample</artifactId>
  <packaging>jar</packaging>
  <version>1.0-SNAPSHOT</version>
  <name>SpringExample</name>
  <url>http://maven.apache.org</url>
  
  <dependencies>
    
        <!-- Spring framework -->
	<dependency>
		<groupId>org.springframework</groupId>
		<artifactId>spring</artifactId>
		<version>2.5.6</version>
	</dependency>
    
        <!-- MySQL database driver -->
	<dependency>
		<groupId>mysql</groupId>
		<artifactId>mysql-connector-java</artifactId>
		<version>5.1.9</version>
	</dependency>
		
  </dependencies>
</project>

3. Customer model

Add a customer model to store customer’s data.

package com.mkyong.customer.model;

import java.sql.Timestamp;

public class Customer 
{
	int custId;
	String name;
	int age;
	//getter and setter methods
	
}

4. Data Access Object (DAO) pattern

Customer Dao interface.

package com.mkyong.customer.dao;

import com.mkyong.customer.model.Customer;

public interface CustomerDAO 
{
	public void insert(Customer customer);
	public Customer findByCustomerId(int custId);
}

Customer Dao implementation, use JDBC to issue a simple insert and select statement.

package com.mkyong.customer.dao.impl;

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import javax.sql.DataSource;
import com.mkyong.customer.dao.CustomerDAO;
import com.mkyong.customer.model.Customer;

public class JdbcCustomerDAO implements CustomerDAO
{
	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) {}
			}
		}
	}
	
	public Customer findByCustomerId(int custId){
		
		String sql = "SELECT * FROM CUSTOMER WHERE CUST_ID = ?";
		
		Connection conn = null;
		
		try {
			conn = dataSource.getConnection();
			PreparedStatement ps = conn.prepareStatement(sql);
			ps.setInt(1, custId);
			Customer customer = null;
			ResultSet rs = ps.executeQuery();
			if (rs.next()) {
				customer = new Customer(
					rs.getInt("CUST_ID"),
					rs.getString("NAME"), 
					rs.getInt("Age")
				);
			}
			rs.close();
			ps.close();
			return customer;
		} catch (SQLException e) {
			throw new RuntimeException(e);
		} finally {
			if (conn != null) {
				try {
				conn.close();
				} catch (SQLException e) {}
			}
		}
	}
}

5. Spring bean configuration

Create the Spring bean configuration file for customerDAO and datasource.

File : Spring-Customer.xml

<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>

File : Spring-Datasource.xml

<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>

File : Spring-Module.xml

<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">

	<import resource="database/Spring-Datasource.xml" />
	<import resource="customer/Spring-Customer.xml" />

</beans>

6. Review project structure

Full directory structure of this example.

7. Run it

package com.mkyong.common;

import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import com.mkyong.customer.dao.CustomerDAO;
import com.mkyong.customer.model.Customer;

public class App 
{
    public static void main( String[] args )
    {
    	ApplicationContext context = 
    		new ClassPathXmlApplicationContext("Spring-Module.xml");
    	 
        CustomerDAO customerDAO = (CustomerDAO) context.getBean("customerDAO");
        Customer customer = new Customer(1, "mkyong",28);
        customerDAO.insert(customer);
    	
        Customer customer1 = customerDAO.findByCustomerId(1);
        System.out.println(customer1);
        
    }
}

output

Customer [age=28, custId=1, name=mkyong]