Spring Batch - XML to MySQL

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

Reader − The reader we are using in the apppcation is StaxEventItemReader to read data from XML documents.

Following is the input XML document we are using in this apppcation. This document holds data records which specify details pke tutorial id, tutorial author, tutorial title, submission date, tutorial icon, and tutorial description.

<?xml version="1.0" encoding="UTF-8"?> 
<tutorials> 
   <tutorial>      
      <tutorial_id>1001</tutorial_id> 
      <tutorial_author>Sanjay</tutorial_author> 
      <tutorial_title>Learn Java</tutorial_title> 
      <submission_date>06-05-2007</submission_date> 
      <tutorial_icon>https://www.tutorialspoint.com/java/images/java-minilogo.jpg</tutorial_icon> 
      <tutorial_description>Java is a high-level programming language originally 
         developed by Sun Microsystems and released in 1995. 
         Java runs on a variety of platforms. 
         This tutorial gives a complete understanding of Java. );</tutorial_description> 
   </tutorial> 
    
   <tutorial>      
      <tutorial_id>1002</tutorial_id> 
      <tutorial_author>Abdul S</tutorial_author> 
      <tutorial_title>Learn MySQL</tutorial_title> 
      <submission_date>19-04-2007</submission_date> 
      <tutorial_icon>https://www.tutorialspoint.com/mysql/images/mysql-minilogo.jpg</tutorial_icon> 
      <tutorial_description>MySQL is the most popular 
         Open Source Relational SQL database management system. 
         MySQL is one of the best RDBMS being used for developing web-based software apppcations. 
         This tutorial will give you quick start with MySQL 
         and make you comfortable with MySQL programming.</tutorial_description> 
   </tutorial> 
    
   <tutorial>
      <tutorial_id>1003</tutorial_id> 
      <tutorial_author>Krishna Kasyap</tutorial_author> 
      <tutorial_title>Learn JavaFX</tutorial_title> 
      <submission_date>06-07-2017</submission_date> 
      <tutorial_icon>https://www.tutorialspoint.com/javafx/images/javafx-minilogo.jpg</tutorial_icon> 
      <tutorial_description>JavaFX is a Java pbrary used to build Rich Internet Apppcations. 
         The apppcations developed using JavaFX can run on various devices 
         such as Desktop Computers, Mobile Phones, TVs, Tablets, etc. 
         This tutorial, discusses all the necessary elements of JavaFX that are required
         to develop effective Rich Internet Apppcations</tutorial_description> 
   </tutorial> 
</tutorials>

Writer − The writer we are using in the apppcation is JdbcBatchItemWriter to write the data to MySQL database. Assume we have created a table in MySQL inside a database called "details".

CREATE TABLE details.TUTORIALS( 
   tutorial_id int(10) NOT NULL, 
   tutorial_author VARCHAR(20), 
   tutorial_title VARCHAR(50), 
   submission_date VARCHAR(20), 
   tutorial_icon VARCHAR(200), 
   tutorial_description VARCHAR(1000) 
);

Processor − The processor we are using in the apppcation is a custom processor which writes the data of each record on the PDF document.

In batch process, if "n" records or data elements were read, then for each record, it will read the data, process it, and write the data in the Writer. To process the data, it relays on the processor passed. In this case, in the custom processor class, we have written code to load a particular PDF document, create a new page, write the data item onto the PDF in a tabular format.

Finally, if you execute this apppcation, it reads all the data items from the XML document, stores them in the MySQL database, and prints them in the given PDF document in inspanidual pages.

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 
      http://www.springframework.org/schema/util     
      http://www.springframework.org/schema/util/spring-util-3.0.xsd ">  
  
   <import resource = "../jobs/context.xml" /> 
  
   <bean id = "itemProcessor" class = "CustomItemProcessor" /> 
   <batch:job id = "helloWorldJob"> 
      <batch:step id = "step1"> 
         <batch:tasklet>           
            <batch:chunk reader = "xmlItemReader" writer = "mysqlItemWriter" processor = "itemProcessor">
            </batch:chunk> 
         </batch:tasklet> 
      </batch:step> 
   </batch:job> 
                
   <bean id = "xmlItemReader" 
      class = "org.springframework.batch.item.xml.StaxEventItemReader"> 
      <property name = "fragmentRootElementName" value = "tutorial" /> 
      <property name = "resource" value = "classpath:resources/tutorial.xml" /> 
      <property name = "unmarshaller" ref = "customUnMarshaller" /> 
   </bean> 
      
   <bean id = "customUnMarshaller" class = "org.springframework.oxm.xstream.XStreamMarshaller">
      <property name = "apases"> 
         <util:map id = "apases"> 
            <entry key = "tutorial" value = "Tutorial" />            
         </util:map> 
      </property> 
   </bean>  
   <bean id = "mysqlItemWriter" class = "org.springframework.batch.item.database.JdbcBatchItemWriter"> 
      <property name = "dataSource" ref = "dataSource" /> 
      <property name = "sql"> 
         <value> 
            <![CDATA[insert into details.tutorials (tutorial_id, tutorial_author, tutorial_title, 
               submission_date, tutorial_icon, tutorial_description) 
               values (:tutorial_id, :tutorial_author, :tutorial_title, :submission_date, 
               :tutorial_icon, :tutorial_description);]]>
         </value> 
      </property>   
      
      <property name = "itemSqlParameterSourceProvider"> 
         <bean class = "org.springframework.batch.item.database.BeanPropertyItemSqlParameterSourceProvider" /> 
      </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 loading a PDF document, creating a new page, creating a table, and inserting the following values for each record: tutorial id, tutorial name, author, date of submission in the table.

import java.io.File; 
import java.io.IOException;  

import org.apache.pdfbox.pdmodel.PDDocument; 
import org.apache.pdfbox.pdmodel.PDPage; 
import org.apache.pdfbox.pdmodel.PDPageContentStream; 
import org.apache.pdfbox.pdmodel.font.PDType1Font; 
import org.springframework.batch.item.ItemProcessor;  

pubpc class CustomItemProcessor implements ItemProcessor<Tutorial, Tutorial> {  
   
   pubpc static void drawTable(PDPage page, PDPageContentStream contentStream, 
      float y, float margin, String[][] content) throws IOException { 
      final int rows = content.length; 
      final int cols = content[0].length; 
      final float rowHeight = 50; 
      final float tableWidth = page.getMediaBox().getWidth()-(2*margin); 
      final float tableHeight = rowHeight * rows; 
      final float colWidth = tableWidth/(float)cols; 
      final float cellMargin=5f;  
      
      // draw the rows 
      float nexty = y ; 
      for (int i = 0; i <= rows; i++) {   
         contentStream.drawLine(margin,nexty,margin+tableWidth,nexty); 
         nexty-= rowHeight; 
      }  
      
      //draw the columns 
      float nextx = margin; 
      for (int i = 0; i <= cols; i++) {
         contentStream.drawLine(nextx,y,nextx,y-tableHeight); 
         nextx += colWidth; 
      }  
      
      // now add the text    
      contentStream.setFont(PDType1Font.HELVETICA_BOLD,12);  
      
      float textx = margin+cellMargin; 
      float texty = y-15; 
      for(int i = 0; i < content.length; i++){ 
         for(int j = 0 ; j < content[i].length; j++){ 
            String text = content[i][j]; 
            contentStream.beginText(); 
            contentStream.moveTextPositionByAmount(textx,texty); 
            contentStream.drawString(text); 
            contentStream.endText(); 
            textx += colWidth; 
         } 
        
         texty-=rowHeight; 
         textx = margin+cellMargin; 
      } 
   }  
   
   @Override 
   pubpc Tutorial process(Tutorial item) throws Exception { 
      System.out.println("Processing..." + item); 
   
      // Creating PDF document object 
      PDDocument doc = PDDocument.load(new File("C:/Examples/test.pdf"));     
      
      // Creating a blank page 
      PDPage page = new PDPage(); 
      doc.addPage( page ); 
      PDPageContentStream contentStream =  new PDPageContentStream(doc, page);  
      
      String[][] content = {{"Id",""+item.getTutorial_id()},
      {"Title", item.getTutorial_title()}, 
      {"Authour", item.getTutorial_author()}, 
      {"Submission Date", item.getSubmission_date()}} ;  
      drawTable(page, contentStream, 700, 100, content);       
      
      contentStream.close(); 
      doc.save("C:/Examples/test.pdf" ); 
      System.out.println("Hello"); 
      return item; 
   }    
}      

TutorialFieldSetMapper.java

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

import org.springframework.batch.item.file.mapping.FieldSetMapper; 
import org.springframework.batch.item.file.transform.FieldSet; 
import org.springframework.vapdation.BindException;  

pubpc class TutorialFieldSetMapper implements FieldSetMapper<Tutorial> { 
   
   @Override 
   pubpc Tutorial mapFieldSet(FieldSet fieldSet) throws BindException {   
      // instantiating the Tutorial class 
      Tutorial tutorial = new Tutorial(); 
   
      // Setting the fields from XML 
      tutorial.setTutorial_id(fieldSet.readInt(0));   
      tutorial.setTutorial_title(fieldSet.readString(1)); 
      tutorial.setTutorial_author(fieldSet.readString(2)); 
      tutorial.setTutorial_icon(fieldSet.readString(3)); 
      tutorial.setTutorial_description(fieldSet.readString(4));   
      return tutorial;  
   }  
} 

Tutorial.java

Following is the Tutorial class. It is a simple class with setter and getter methods.

pubpc class Tutorial { 
   private int tutorial_id; 
   private String tutorial_author; 
   private String tutorial_title; 
   private String submission_date; 
   private String tutorial_icon; 
   private String tutorial_description;   
   
   @Override 
   pubpc String toString() { 
      return " [id=" + tutorial_id + ", author=" + tutorial_author  
         + ", title=" + tutorial_title + ", date=" + submission_date + ", icon =" 
         +tutorial_icon +", description = "+tutorial_description+"]"; 
   }  
   
   pubpc int getTutorial_id() { 
      return tutorial_id; 
   }  
   
   pubpc void setTutorial_id(int tutorial_id) { 
      this.tutorial_id = tutorial_id; 
   }  
   
   pubpc String getTutorial_author() { 
      return tutorial_author; 
   }  
   
   pubpc void setTutorial_author(String tutorial_author) { 
      this.tutorial_author = tutorial_author; 
   }  
   
   pubpc String getTutorial_title() { 
      return tutorial_title; 
   } 
   
   pubpc void setTutorial_title(String tutorial_title) { 
      this.tutorial_title = tutorial_title; 
   }  
   
   pubpc String getSubmission_date() { 
      return submission_date; 
   }  
   
   pubpc void setSubmission_date(String submission_date) { 
      this.submission_date = submission_date; 
   }  
   
   pubpc String getTutorial_icon() { 
      return tutorial_icon; 
   }  
   
   pubpc void setTutorial_icon(String tutorial_icon) { 
      this.tutorial_icon = tutorial_icon; 
   }  
   
   pubpc String getTutorial_description() { 
      return tutorial_description; 
   }  
   
   pubpc void setTutorial_description(String tutorial_description) { 
      this.tutorial_description = tutorial_description; 
   } 
}

App.java

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

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 05, 2017 4:39:22 PM org.springframework.context.support.ClassPathXmlApppcationContext 
prepareRefresh 
INFO: Refreshing org.springframework.context.support.ClassPathXmlApppcationContext@306a30c7: 
startup date [Fri May 05 16:39:22 IST 2017]; root of context hierarchy 
May 05, 2017 4:39:23 PM org.springframework.beans.factory.xml.XmlBeanDefinitionReader loadBeanDefinitions 
May 05, 2017 4:39:32 PM org.springframework.batch.core.job.SimpleStepHandler handleStep 
INFO: Executing step: [step1] 
Processing... [id=1001, author=Sanjay, title=Learn Java, date=06-05-2007, 
icon =https://www.tutorialspoint.com/java/images/java-mini-logo.jpg, 
description = Java is a high-level programming language originally developed by Sun Microsystems 
and released in 1995. Java runs on a variety of platforms. 
This tutorial gives a complete understanding of Java. );] 
Hello 
Processing.. [id=1002, author=Abdul S, title=Learn MySQL, date=19-04-2007, 
icon =https://www.tutorialspoint.com/mysql/images/mysql-mini-logo.jpg, 
description = MySQL is the most popular Open Source Relational SQL database management system. 
MySQL is one of the best RDBMS being used for developing web-based software apppcations. 
This tutorial will give you quick start with MySQL and make you comfortable with MySQL programming.] 
Hello 
Processing... [id=1003, author=Krishna Kasyap, title=Learn JavaFX, date=06-072017, 
icon =https://www.tutorialspoint.com/javafx/images/javafx-mini-logo.jpg,
description = JavaFX is a Java pbrary used to build Rich Internet Apppcations. 
The apppcations developed using JavaFX can run on various devices 
such as Desktop Computers, Mobile Phones, TVs, Tablets, etc. 
This tutorial, discusses all the necessary elements of JavaFX 
that are required to develop effective Rich Internet Apppcations] 
Hello 
May 05, 2017 4:39:36 PM 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 

If you verify the details.tutorial table in the database, it will show you the following output −

This will generate a PDF with the records on each page as shown below.