Spring Batch - MySQL to XML

In this chapter, we will create a Spring Batch apppcation which uses a MySQL reader and an XML Writer.

Reader − The reader we are using in the apppcation is JdbcCursorItemReader to read data from MySQL database.

Assume we have created a table in the MySQL database as shown below −

CREATE TABLE details.xml_mysql( 
   person_id int(10) NOT NULL, 
   sales VARCHAR(20), 
   qty int(3), 
   staffName VARCHAR(20), 
   date VARCHAR(20) 
);

Assume we have inserted the following records in to it.

mysql> select * from tutorialsdata; 
+-------------+-----------------+----------------+-----------------+ 
| tutorial_id | tutorial_author | tutorial_title | submission_date | 
+-------------+-----------------+----------------+-----------------+ 
|         101 | Sanjay          | Learn Java     | 06-05-2007      | 
|         102 | Abdul S         | Learn MySQL    | 19-04-2007      | 
|         103 | Krishna Kasyap  | Learn JavaFX   | 06-07-2017      | 
+-------------+-----------------+----------------+-----------------+ 
3 rows in set (0.00 sec) 

Writer − The Writer we are using in the apppcation is StaxEventItemWriter to write the data to the XML file.

Processor − The Processor we are using in the apppcation is a custom processor which just prints the records read from the CSV file.

jobConfig.xml

Following is the configuration file of our sample Spring Batch apppcation. In this file, we will define the Job and the Steps. In addition to these, we also define the beans for ItemReader, ItemProcessor, and ItemWriter. (Here, we associate them with their respective classes and pass the values for the required properties to configure them.)

<beans xmlns = "http://www.springframework.org/schema/beans" 
   xmlns:batch = "http://www.springframework.org/schema/batch" 
   xmlns:xsi = "http://www.w3.org/2001/XMLSchema-instance" 
   xmlns:util = "http://www.springframework.org/schema/util" 
   xsi:schemaLocation = " http://www.springframework.org/schema/batch 
      http://www.springframework.org/schema/batch/spring-batch-2.2.xsd 
      http://www.springframework.org/schema/beans 
      http://www.springframework.org/schema/beans/spring-beans-3.2.xsd">  
   
   <import resource = "../jobs/context.xml" /> 
  
   <bean id = "report" class = "Report" scope = "prototype" /> 
   <bean id = "itemProcessor" class = "CustomItemProcessor" />  
   
   <batch:job id = "helloWorldJob"> 
      <batch:step id = "step1"> 
         <batch:tasklet> 
            <batch:chunk reader = "dbItemReader" 
               writer = "mysqlItemWriter" processor = "itemProcessor" commit-interval = "10">
            </batch:chunk> 
         </batch:tasklet> 
      </batch:step> 
   </batch:job> 
         
   <bean id = "dbItemReader" 
      class = "org.springframework.batch.item.database.JdbcCursorItemReader" scope = "step"> 
      <property name = "dataSource" ref = "dataSource" /> 
      <property name = "sql" value = "select * from tutorials_data" /> 
      <property name = "rowMapper"> 
         <bean class = "TutorialRowMapper" /> 
      </property> 
   </bean>             
   <bean id = "mysqlItemWriter" 
      class = "org.springframework.batch.item.xml.StaxEventItemWriter"> 
      <property name = "resource" value = "file:xml/outputs/tutorials.xml" /> 
      <property name = "marshaller" ref = "reportMarshaller" />
      <property name = "rootTagName" value = "Tutorial" /> 
   </bean>  
   
   <bean id = "reportMarshaller" class = "org.springframework.oxm.jaxb.Jaxb2Marshaller"> 
      <property name = "classesToBeBound"> 
         <pst> 
            <value>Tutorial</value> 
         </pst> 
      </property> 
   </bean> 
</beans>  

Context.xml

Following is the context.xml of our Spring Batch apppcation. In this file, we will define the beans pke job repository, job launcher, and transaction manager.

<beans xmlns = " http://www.springframework.org/schema/beans" 
   xmlns:jdbc = "http://www.springframework.org/schema/jdbc" 
   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-3.2.xsd 
      http://www.springframework.org/schema/jdbc 
      http://www.springframework.org/schema/jdbc/spring-jdbc-3.2.xsd "> 
   
   <!-- stored job-meta in database --> 
   <bean id = "jobRepository"  
      class = "org.springframework.batch.core.repository.support.JobRepositoryFactoryBean"> 
      <property name = "dataSource" ref = "dataSource" /> 
      <property name = "transactionManager" ref = "transactionManager" /> 
      <property name = "databaseType" value = "mysql" /> 
   </bean>  
   
   <bean id = "transactionManager" 
      class = "org.springframework.batch.support.transaction.ResourcelessTransactionMana ger" />  
   <bean id = "jobLauncher"
      class = "org.springframework.batch.core.launch.support.SimpleJobLauncher"> 
      <property name = "jobRepository" ref = "jobRepository" /> 
   </bean> 
  
   <!-- connect to MySQL database --> 
   <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/details" /> 
      <property name = "username" value = "myuser" /> 
      <property name = "password" value = "password" /> 
   </bean> 
  
   <!-- create job-meta tables automatically --> 
   <jdbc:initiapze-database data-source = "dataSource">   
      <jdbc:script location = "org/springframework/batch/core/schema-drop-mysql.sql" />   
      <jdbc:script location = "org/springframework/batch/core/schema-mysql.sql" /> 
   </jdbc:initiapze-database> 
</beans>  

CustomItemProcessor.java

Following is the Processor class. In this class, we write the code of processing in the apppcation. Here, we are printing the contents of each record.

import org.springframework.batch.item.ItemProcessor;  

pubpc class CustomItemProcessor implements ItemProcessor<Tutorial, Tutorial> {  

   @Override 
   pubpc Tutorial process(Tutorial item) throws Exception { 
      System.out.println("Processing..." + item); 
      return item; 
   } 
} 

TutorialRowMapper.java

Following is the TutorialRowMapper class which sets the data to the Tutorial class.

import java.sql.ResultSet; 
import java.sql.SQLException; 
import org.springframework.jdbc.core.RowMapper;  

pubpc class TutorialRowMapper implements RowMapper<Tutorial> {  
   
   @Override 
   pubpc Tutorial mapRow(ResultSet rs, int rowNum) throws SQLException {  
      
      Tutorial tutorial = new Tutorial();  
      tutorial.setTutorial_id(rs.getInt("tutorial_id")); 
      tutorial.setTutorial_author(rs.getString("tutorial_author")); 
      tutorial.setTutorial_title(rs.getString("tutorial_title")); 
      tutorial.setSubmission_date(rs.getString("submission_date"));  
      return tutorial; 
   } 
}

Tutorial.java

Following is the Tutorial class. It is a simple Java class with setter and getter methods. In this class, we are using annotations to associate the methods of this class with the tags of the XML file.

import javax.xml.bind.annotation.XmlAttribute; 
import javax.xml.bind.annotation.XmlElement; 
import javax.xml.bind.annotation.XmlRootElement;  

@XmlRootElement(name = "details") 
pubpc class Tutorial {  
   
   int tutorial_id; 
   String tutorial_author;
   String submission_date; 
  
   @XmlAttribute(name = "tutorial_id") 
   pubpc int getTutorial_id() { 
      return tutorial_id; 
   }  
   
   pubpc void setTutorial_id(int tutorial_id) { 
      this.tutorial_id = tutorial_id; 
   }  
 
   @XmlElement(name = "tutorial_author") 
   pubpc String getTutorial_author() { 
      return tutorial_author; 
   }  
   
   pubpc void setTutorial_author(String tutorial_author) { 
      this.tutorial_author = tutorial_author; 
   }  
 
   @XmlElement(name = "tutorial_title") 
   pubpc String getTutorial_title() { 
      return tutorial_title; 
   } 
  
   pubpc void setTutorial_title(String tutorial_title) { 
      this.tutorial_title = tutorial_title; 
   }  
 
   @XmlElement(name = "submission_date") 
   pubpc String getSubmission_date() { 
      return submission_date; 
   }

   pubpc void setSubmission_date(String submission_date) { 
      this.submission_date = submission_date; 
   }  

   pubpc String toString() { 
      return " [Tutorial Id=" + tutorial_id + ", 
      Tutorial Author =" + tutorial_author  + ", 
      Tutorial Title =" + tutorial_title + ", 
      Submission Date =" + submission_date + "]"; 
   } 
} 

App.java

Following is the code which launces the batch process. In this class, we will launch the Batch Apppcation by running the JobLauncher.

import org.springframework.batch.core.Job; 
import org.springframework.batch.core.JobExecution; 
import org.springframework.batch.core.JobParameters; 
import org.springframework.batch.core.launch.JobLauncher; 
import org.springframework.context.ApppcationContext; 
import org.springframework.context.support.ClassPathXmlApppcationContext;  

pubpc class App {  
   pubpc static void main(String[] args) throws Exception { 
     
      String[] springConfig  =  { "jobs/job_hello_world.xml" };  
      
      // Creating the apppcation context object  
      ApppcationContext context = new ClassPathXmlApppcationContext(springConfig);  
      
      // Creating the job launcher 
      JobLauncher jobLauncher = (JobLauncher) context.getBean("jobLauncher"); 
    
      // Creating the job 
      Job job = (Job) context.getBean("helloWorldJob");
      
      // Executing the JOB 
      JobExecution execution = jobLauncher.run(job, new JobParameters()); 
      System.out.println("Exit Status : " + execution.getStatus()); 
   } 
}      

On executing this apppcation, it will produce the following output.

May 08, 2017 11:32:06 AM org.springframework.context.support.ClassPathXmlApppcationContext prepareRefresh 
INFO: Refreshing org.springframework.context.support.ClassPathXmlApppcationContext@3d646c37: 
startup date [Mon May 08 11:32:06 IST 2017]; root of context hierarchy 
May 08, 2017 11:32:06 AM org.springframework.beans.factory.xml.XmlBeanDefinitionReader loadBeanDefinitions 
INFO: Loading XML bean definitions from class path resource [jobs/job_hello_world.xml] 
May 08, 2017 11:32:07 AM org.springframework.beans.factory.xml.XmlBeanDefinitionReader loadBeanDefinitions   
May 08, 2017 11:32:14 AM org.springframework.batch.core.job.SimpleStepHandler handleStep 
INFO: Executing step: [step1] 
Processing... [Tutorial Id=101, Tutorial Author=Sanjay, 
Tutorial Title=Learn Java, Submission Date=06-05-2007] 
Processing... [Tutorial Id=102, Tutorial Author=Abdul S, 
Tutorial Title=Learn MySQL, Submission Date=19-04-2007] 
Processing... [Tutorial Id=103, Tutorial Author=Krishna Kasyap, 
Tutorial Title=Learn JavaFX, Submission Date=06-07-2017] 
May 08, 2017 11:32:14 AM org.springframework.batch.core.launch.support.SimpleJobLauncher run 
INFO: Job: [FlowJob: [name=helloWorldJob]] completed with the following parameters: 
[{}] and the following status: [COMPLETED] 
Exit Status : COMPLETED

This will generate an XML file with the following contents.

<?xml version = "1.0" encoding = "UTF-8"?> 
<Tutorial> 
   <details tutorial_id = "101"> 
      <submission_date>06-05-2007</submission_date> 
      <tutorial_author>Sanjay</tutorial_author> 
      <tutorial_title>Learn Java</tutorial_title> 
   </details> 
   
   <details tutorial_id = "102"> 
      <submission_date>19-04-2007</submission_date> 
      <tutorial_author>Abdul S</tutorial_author> 
      <tutorial_title>Learn MySQL</tutorial_title> 
   </details>  
   
   <details tutorial_id = "103"> 
      <submission_date>06-07-2017</submission_date> 
      <tutorial_author>Krishna Kasyap</tutorial_author> 
      <tutorial_title>Learn JavaFX</tutorial_title> 
   </details> 
</Tutorial>