In this tutorial, we will see Spring Batch StaxEventItemReader Example. We will see how to read XML data in the spring batch using StaxEventItemReader class and store it in the MySql database. Let’s see what we are going to do in this example.
Consider we have an XML file.
<?xml version="1.0" encoding="UTF-8"?>
<students>
<student>
<id>1</id>
<name>John</name>
<rollNumber>0126CS090</rollNumber>
</student>
<student>
<id>2</id>
<name>Arya</name>
<rollNumber>0126CS090</rollNumber>
</student>
<student>
<id>3</id>
<name>Will</name>
<rollNumber>0126CS090</rollNumber>
</student>
<student>
<id>4</id>
<name>Smith</name>
<rollNumber>0126CS090</rollNumber>
</student>
<student>
<id>5</id>
<name>Rock</name>
<rollNumber>0126CS090</rollNumber>
</student>
</students>We will read the above XML file using StaxEventItemReader class and write it back to the database.
StaxEventItemReader configuration
public StaxEventItemReader xmlItemReader() {
return new StaxEventItemReaderBuilder<Student>()
.name("itemReader")
.resource(new ClassPathResource("data.xml"))
.addFragmentRootElements("student")
.unmarshaller(studentMarshaller())
.build();
}
public XStreamMarshaller studentMarshaller() {
Map<String, Class> aliases = new HashMap<>();
aliases.put("student", Student.class);
aliases.put("id", Long.class);
aliases.put("rollNumber", String.class);
aliases.put("name", String.class);
XStreamMarshaller marshaller = new XStreamMarshaller();
marshaller.setAliases(aliases);
return marshaller;
}Let’s see Spring Batch StaxEventItemReader Example using Spring Boot and MySql.
Before going ahead create a student table.
CREATE TABLE student
(
id int NOT NULL PRIMARY KEY AUTO_INCREMENT,
name VARCHAR(260),
roll_number VARCHAR(260)
);Maven dependency
<?xml version="1.0" encoding="UTF-8"?>
<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/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.javatute.com</groupId>
<artifactId>springbatchxmlitemreader</artifactId>
<version>1.0-SNAPSHOT</version>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.3.1.RELEASE</version>
</parent>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.batch</groupId>
<artifactId>spring-batch-core</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-batch</artifactId>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
</dependency>
<!-- https://mvnrepository.com/artifact/org.springframework/spring-oxm -->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-oxm</artifactId>
</dependency>
<dependency>
<groupId>com.thoughtworks.xstream</groupId>
<artifactId>xstream</artifactId>
<version>1.4.11.1</version>
</dependency>
</dependencies>
<properties>
<maven.compiler.source>8</maven.compiler.source>
<maven.compiler.target>8</maven.compiler.target>
</properties>
</project>package structure
Define Student.java
package com.springbatchexample.entity;
public class Student {
private Long id;
private String name;
private String rollNumber;
public Student() {
}
public Student(Long id, String name, String rollNumber) {
this.id = id;
this.name = name;
this.rollNumber = rollNumber;
}
public Long getId() {
return id;
}
public void setId(Long id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getRollNumber() {
return rollNumber;
}
public void setRollNumber(String rollNumber) {
this.rollNumber = rollNumber;
}
}Define StudentItemProcessor.java
package com.springbatchexample.config;
import com.springbatchexample.entity.Student;
import org.springframework.batch.item.ItemProcessor;
public class StudentItemProcessor implements ItemProcessor<Student, Student> {
@Override
public Student process(Student student) throws Exception {
return student;
}
}
The StudentItemProcessor can be used to perform any transformations or validation that we need on an item(i.e student) before Spring Batch sends it to the ItemWriter. we are not performing transformations or validation for item.
Define SpringBatchConfig file
package com.springbatchexample.config;
import com.springbatchexample.entity.Student;
import org.springframework.batch.core.Job;
import org.springframework.batch.core.Step;
import org.springframework.batch.core.configuration.annotation.EnableBatchProcessing;
import org.springframework.batch.core.configuration.annotation.JobBuilderFactory;
import org.springframework.batch.core.configuration.annotation.StepBuilderFactory;
import org.springframework.batch.core.job.builder.FlowJobBuilder;
import org.springframework.batch.core.job.builder.JobBuilder;
import org.springframework.batch.core.launch.support.RunIdIncrementer;
import org.springframework.batch.core.step.builder.SimpleStepBuilder;
import org.springframework.batch.core.step.builder.StepBuilder;
import org.springframework.batch.item.database.BeanPropertyItemSqlParameterSourceProvider;
import org.springframework.batch.item.database.JdbcBatchItemWriter;
import org.springframework.batch.item.xml.StaxEventItemReader;
import org.springframework.batch.item.xml.builder.StaxEventItemReaderBuilder;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.core.io.ClassPathResource;
import org.springframework.oxm.xstream.XStreamMarshaller;
import javax.sql.DataSource;
import java.util.HashMap;
import java.util.Map;
@EnableBatchProcessing
@Configuration
public class SpringBatchConfig {
@Autowired
private DataSource dataSource;
@Autowired
private JobBuilderFactory jobBuilderFactory;
@Autowired
private StepBuilderFactory stepBuilderFactory;
public StaxEventItemReader xmlItemReader() {
return new StaxEventItemReaderBuilder<Student>()
.name("itemReader")
.resource(new ClassPathResource("data.xml"))
.addFragmentRootElements("student")
.unmarshaller(studentMarshaller())
.build();
}
public XStreamMarshaller studentMarshaller() {
Map<String, Class> aliases = new HashMap<>();
aliases.put("student", Student.class);
aliases.put("id", Long.class);
aliases.put("rollNumber", String.class);
aliases.put("name", String.class);
XStreamMarshaller marshaller = new XStreamMarshaller();
marshaller.setAliases(aliases);
return marshaller;
}
@Bean
public StudentItemProcessor processor() {
return new StudentItemProcessor();
}
@Bean
public JdbcBatchItemWriter<Student> writer() {
JdbcBatchItemWriter<Student> writer = new JdbcBatchItemWriter<>();
writer.setItemSqlParameterSourceProvider(new BeanPropertyItemSqlParameterSourceProvider<>());
writer.setSql("insert into student(id,roll_number,name) values (:id,:rollNumber,:name)");
writer.setDataSource(dataSource);
return writer;
}
@Bean
public Job writeStudentDataIntoSqlDb() {
JobBuilder jobBuilder = jobBuilderFactory.get("STUDENT_JOB");
jobBuilder.incrementer(new RunIdIncrementer());
FlowJobBuilder flowJobBuilder = jobBuilder.flow(getFirstStep()).end();
Job job = flowJobBuilder.build();
return job;
}
@Bean
public Step getFirstStep() {
StepBuilder stepBuilder = stepBuilderFactory.get("getFirstStep");
SimpleStepBuilder<Student, Student> simpleStepBuilder = stepBuilder.chunk(1);
return simpleStepBuilder.reader(xmlItemReader()).processor(processor()).writer(writer()).build();
}
}
The XStreamMarshallerclass is available in org.springframework.oxm.xstream.XStreamMarshaller package. This class doesn’t require extra configuration. It can unmarshal any class that is in the classpath. We need to set the encoding used for writing to OutputStreams. It defaults to UTF-8.
application.properties
spring.datasource.url=jdbc:mysql://localhost:3306/springbootcrudexample
spring.datasource.username=root
spring.datasource.password=root
spring.jpa.hibernate.ddl-auto=create
spring.jpa.show-sql=true
spring.jpa.properties.hibernate.format_sql=true
server.port = 9091
spring.batch.initialize-schema=always Define SpringMain class
package com.springbatchexample.main;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.boot.autoconfigure.domain.EntityScan;
import org.springframework.context.annotation.ComponentScan;
@SpringBootApplication
@ComponentScan(basePackages = "com.springbatchexample.*")
public class SpringMain {
public static void main(String[] args) {
SpringApplication.run(SpringMain.class, args);
}
}
After running the above example we should be able to see the below records in the database.
That’s all about Spring Batch StaxEventItemReader Example.
Download code from GitHub.
See docs
Other Spring Batch tutorial.
- Spring Batch FlatFileItemReader Example
- StoredProcedureItemReader example
- JdbcCursorItemReader Spring Batch Example
- JsonItemReader Spring Batch Example
Spring Data JPA Example.
- Spring Data JPA greater than Example
- Spring Data JPA less than Example
- Spring Data JPA IsNull Example Using Spring Boot
- Spring Data findById() Vs getOne()
- Spring Data JPA CrudRepository findById()
- Spring Data JPA JpaRepository getOne()
- Spring Data CrudRepository saveAll() and findAll().
- Spring Data CrudRepository existsById()
- Spring Data JPA delete() vs deleteInBatch()
- Spring Data JPA deleteAll() Vs deleteAllInBatch()
- Spring Data JPA JpaRepository deleteAllInBatch()
- Spring Data JPA deleteInBatch() Example
- Spring Data JPA JpaRepository saveAndFlush() Example
- Spring Data JPA CrudRepository count() Example
- Spring Data JPA CrudRepository delete() and deleteAll()
- Spring Data JPA CrudRepository deleteById() Example
- CrudRepository findAllById() Example Using Spring Boot
- Spring Data CrudRepository save() Method.
- Sorting in Spring Data JPA using Spring Boot.
- Spring Data JPA example using spring boot.
- Spring Data JPA and its benefit.
Hibernate example using spring boot.
- @Version Annotation Example In Hibernate.
- Hibernate Validator Constraints Example Using Spring Boot.
- @Temporal Annotation Example In Hibernate/Jpa Using Spring Boot.
- Hibernate Table Per Concrete Class Spring Boot.
- Hibernate Table Per Subclass Inheritance Spring Boot.
- Hibernate Single Table Inheritance using Spring Boot.
- One To One Mapping Annotation Example in Hibernate/JPA using Spring Boot and Oracle.
- One To One Bidirectional Mapping Example In Hibernate/JPA Using Spring Boot and Oracle.
- One To Many Mapping Annotation Example In Hibernate/JPA Using Spring Boot And Oracle.
- Many To One Unidirectional Mapping In Hibernate/JPA Annotation Example Using Spring Boot and Oracle.
- One To Many Bidirectional Mapping In Hibernate/JPA Annotation Example Using Spring Boot and Oracle.
- Many To Many Mapping Annotation Example In Hibernate/JPA Using Spring Boot
