Spring + JDBC 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

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]