Basic Spring Code with Maven

This blog shows how we can use a simple maven project and work with Spring to interact with a database.
First, we create a simple project using the maven command..

mvn archetype:generate

We select the maven-archetype-quickstart project (option 15)
Run the command

mvn eclipse:m2eclipse

to create the .classpath and .project files for eclipse.
We will create a file beans.xml in src/main/resources dir. Not creating the beans.xml file in the resources dir will give you the following exception:
Exception in thread “main” org.springframework.beans.factory.BeanDefinitionStoreException: IOException parsing XML document from class path resource [beans.xml]; nested exception is java.io.FileNotFoundException: class path resource [beans.xml] cannot be opened because it does not exist

Here is my beans.xml file.

<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">
 <property name="driverClassName" value="com.mysql.jdbc.Driver"></property>
 <property name="url" value="jdbc:mysql://localhost:3306/database-name"></property>
 <property name="username" value="root"></property>
 <property name="password" value="root"></property>
 </bean>
 <bean id="template">
 <property name="dataSource" ref="dataSource"></property>
 </bean>
 <bean id="mySQLDao">
 <property name="template" ref="template"></property>
 </bean>
</beans>

Create a main class with the following code:

ApplicationContext context = new ClassPathXmlApplicationContext("beans.xml");
MySQLDao mySQLDao = (MySQLDao)context.getBean("mySQLDao");
System.out.println(mySQLDao.queryForDate());

In MySQLDao we have the following code:

 private JdbcTemplate template;

 public Date queryForDate(){
 String sql = "select now() from dual;";
 Date currentDate = (Date)template.queryForObject(sql, Date.class);
 return currentDate;
 }

 public void setTemplate(JdbcTemplate template) {
 this.template = template;
 }

In pom.xml add the following dependencies:

<dependency>
 <groupId>org.springframework</groupId>
 <artifactId>spring-core</artifactId>
 <version>2.5.6</version>
 <scope>compile</scope>
 </dependency>
 <dependency>
 <groupId>org.springframework</groupId>
 <artifactId>spring-jdbc</artifactId>
 <version>2.5.6</version>
 <scope>compile</scope>
 </dependency>
 <dependency>
 <groupId>org.springframework</groupId>
 <artifactId>spring-context</artifactId>
 <version>2.5.6</version>
 <scope>compile</scope>
 </dependency>
 <dependency>
 <groupId>mysql</groupId>
 <artifactId>mysql-connector-java</artifactId>
 <version>5.1.11</version>
 <scope>compile</scope>
 </dependency>

If the mysql-connector jar is not installed in the local repository , use the following command to install the jar.

mvn install:install-file -DgroupId=mysql -DartifactId=mysql-connector-java -Dversion=5.1.11 -Dfile=mysql-connector-java-5.1.11-bin.jar -DgeneratePom=true -Dpackaging=jar

Running the main class should now give the current timestamp from the database.
To run main from the command line use the following command

mvn exec:java -Dexec.mainClass="com.wordpress.codesilo.Main"