Refactored spring batch example

Author: nilandev

spring-batch-demo/src/main/java/com/stacktips/app/SpringBatchDemoApplication.java

@@ -6,8 +6,8 @@
 @SpringBootApplication
 public class SpringBatchDemoApplication {
 
-    public static void main(String[] args) {
-        SpringApplication.run(SpringBatchDemoApplication.class, args);
-    }
+	public static void main(String[] args) {
+		SpringApplication.run(SpringBatchDemoApplication.class, args);
+	}
 
 }

spring-batch-demo/src/main/java/com/stacktips/app/config/ApplicationEvent.java

@@ -0,0 +1,26 @@
+package com.stacktips.app.config;
+
+import lombok.RequiredArgsConstructor;
+import org.springframework.batch.core.Job;
+import org.springframework.batch.core.JobExecutionException;
+import org.springframework.batch.core.JobParametersBuilder;
+import org.springframework.batch.core.launch.JobLauncher;
+import org.springframework.boot.context.event.ApplicationReadyEvent;
+import org.springframework.context.event.EventListener;
+import org.springframework.stereotype.Component;
+
+@Component
+@RequiredArgsConstructor
+public class ApplicationEvent {
+
+    private final JobLauncher jobLauncher;
+    private final Job csvImporterJob;
+
+    @EventListener(ApplicationReadyEvent.class)
+    public void applicationEvent() throws JobExecutionException {
+        jobLauncher.run(csvImporterJob, new JobParametersBuilder()
+                .addString("ignoreCountry", "India")
+                .toJobParameters());
+
+    }
+}

spring-batch-demo/src/main/java/com/stacktips/app/config/BatchConfig.java

@@ -0,0 +1,97 @@
+package com.stacktips.app.config;
+
+import com.stacktips.app.model.Customer;
+import com.stacktips.app.utils.DateUtils;
+import jakarta.persistence.EntityManagerFactory;
+import org.springframework.batch.core.*;
+import org.springframework.batch.core.configuration.annotation.EnableBatchProcessing;
+import org.springframework.batch.core.job.builder.JobBuilder;
+import org.springframework.batch.core.launch.support.RunIdIncrementer;
+import org.springframework.batch.core.repository.JobRepository;
+import org.springframework.batch.core.step.builder.StepBuilder;
+import org.springframework.batch.item.ItemReader;
+import org.springframework.batch.item.ItemWriter;
+import org.springframework.batch.item.database.JpaItemWriter;
+import org.springframework.batch.item.database.builder.JpaItemWriterBuilder;
+import org.springframework.batch.item.file.FlatFileItemReader;
+import org.springframework.batch.item.file.builder.FlatFileItemReaderBuilder;
+import org.springframework.batch.item.file.mapping.BeanWrapperFieldSetMapper;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.core.io.ClassPathResource;
+import org.springframework.transaction.PlatformTransactionManager;
+
+@Configuration
+@EnableBatchProcessing
+public class BatchConfig {
+
+    @Bean
+    public FlatFileItemReader<Customer> reader() {
+        return new FlatFileItemReaderBuilder<Customer>()
+                .linesToSkip(1)
+                .name("csvItemReader")
+                .resource(new ClassPathResource("customers.csv"))
+                .delimited()
+                .delimiter(",")
+                .names("index", "customerId", "firstName", "lastName", "company",
+                        "city", "country", "phone1",
+                        "phone2", "email", "subscriptionDate", "website")
+                .fieldSetMapper(fieldSet -> {
+                    return Customer.builder()
+                            .customerId(fieldSet.readString("customerId"))
+                            .firstName(fieldSet.readString("firstName"))
+                            .lastName(fieldSet.readString("lastName"))
+                            .company(fieldSet.readString("company"))
+                            .city(fieldSet.readString("city"))
+                            .country(fieldSet.readString("country"))
+                            .phone1(fieldSet.readString("phone1"))
+                            .phone2(fieldSet.readString("phone2"))
+                            .email(fieldSet.readString("email"))
+                            .website(fieldSet.readString("website"))
+                            .subscriptionDate(DateUtils.parseDate(fieldSet.readString("subscriptionDate")))
+                            .build();
+                })
+                .build();
+
+    }
+
+
+    @Bean
+    public JpaItemWriter<Customer> writer(EntityManagerFactory entityManagerFactory) {
+        return new JpaItemWriterBuilder<Customer>()
+                .entityManagerFactory(entityManagerFactory)
+                .build();
+    }
+
+    @Bean
+    public Step csvImporterStep(ItemReader<Customer> reader, ItemWriter<Customer> writer,
+                                JobRepository jobRepository, PlatformTransactionManager transactionManager,
+                                CustomJobProcessor processor) {
+        return new StepBuilder("csvImporterStep", jobRepository)
+                .<Customer, Customer>chunk(50, transactionManager)
+                .reader(reader)
+                .processor(processor)
+                .writer(writer)
+                .allowStartIfComplete(true)
+                .build();
+    }
+
+    @Bean
+    public Job csvImporterJob(Step csvImporterStep, JobRepository jobRepository, ImportJobListener listener) {
+        return new JobBuilder("csvImporterJob", jobRepository)
+                .incrementer(new RunIdIncrementer())
+                .validator(new JobParametersValidator() {
+                    @Override
+                    public void validate(JobParameters parameters) throws JobParametersInvalidException {
+                        if ("Costa Rica".equals(parameters.getString("ignoreCountry"))) {
+                            throw new JobParametersInvalidException("Invalid configuration");
+                        }
+                    }
+                })
+                .listener(listener)
+                .flow(csvImporterStep)
+                .end()
+                .build();
+    }
+
+}

spring-batch-demo/src/main/java/com/stacktips/app/config/CustomJobProcessor.java

@@ -0,0 +1,28 @@
+package com.stacktips.app.config;
+
+import com.stacktips.app.model.Customer;
+import lombok.extern.slf4j.Slf4j;
+import org.springframework.batch.core.configuration.annotation.JobScope;
+import org.springframework.batch.item.ItemProcessor;
+import org.springframework.beans.factory.annotation.Value;
+import org.springframework.stereotype.Component;
+
+@Slf4j
+@JobScope
+@Component
+public class CustomJobProcessor implements ItemProcessor<Customer, Customer> {
+
+    private final String ignoreCountry;
+
+    public CustomJobProcessor(@Value("#{jobParameters['ignoreCountry']}") String ignoreCountry) {
+        this.ignoreCountry = ignoreCountry;
+    }
+
+    @Override
+    public Customer process(Customer item) throws Exception {
+        if (item.getCountry().equals(ignoreCountry)) {
+            log.info("Customer ignored: {}", item.toString());
+        }
+        return item;
+    }
+}

spring-batch-demo/src/main/java/com/stacktips/app/config/ImportJobListener.java

@@ -0,0 +1,26 @@
+package com.stacktips.app.config;
+
+import lombok.extern.slf4j.Slf4j;
+import org.springframework.batch.core.BatchStatus;
+import org.springframework.batch.core.JobExecution;
+import org.springframework.batch.core.JobExecutionListener;
+import org.springframework.stereotype.Component;
+
+@Slf4j
+@Component
+public class ImportJobListener implements JobExecutionListener {
+
+    @Override
+    public void beforeJob(JobExecution jobExecution) {
+        log.info("Job {} started", jobExecution.getJobInstance().getJobName());
+    }
+
+    @Override
+    public void afterJob(JobExecution jobExecution) {
+        if (jobExecution.getStatus() == BatchStatus.COMPLETED) {
+            log.info("Job {} completed", jobExecution.getJobInstance().getJobName());
+        } else if (jobExecution.getStatus() == BatchStatus.FAILED) {
+            log.info("Job {} failed", jobExecution.getJobInstance().getJobName());
+        }
+    }
+}

spring-batch-demo/src/main/java/com/stacktips/app/config/SpringBatchConfig.java

@@ -1,4 +1,4 @@
-package com.stacktips.app.models;
+package com.stacktips.app.model;
 
 import jakarta.persistence.Entity;
 import jakarta.persistence.Id;
@@ -19,15 +19,15 @@
 public class Customer {
 
     @Id
-    private String customerId;
-    private String firstName;
-    private String lastName;
-    private String company;
-    private String city;
-    private String country;
-    private String phone1;
-    private String phone2;
-    private String email;
-    private LocalDate subscriptionDate;
-    private String website;
-}
+    String customerId;
+    String firstName;
+    String lastName;
+    String company;
+    String city;
+    String country;
+    String phone1;
+    String phone2;
+    String email;
+    LocalDate subscriptionDate;
+    String website;
+}

spring-batch-demo/src/main/java/com/stacktips/app/models/Customer.java renamed to spring-batch-demo/src/main/java/com/stacktips/app/model/Customer.java

@@ -1,10 +1,7 @@
 package com.stacktips.app.repository;
 
-import com.stacktips.app.models.Customer;
+import com.stacktips.app.model.Customer;
 import org.springframework.data.jpa.repository.JpaRepository;
-import org.springframework.stereotype.Repository;
-
-@Repository
-public interface CustomerRepository extends JpaRepository<Customer, Integer> {
 
+public interface CustomerRepository extends JpaRepository<Customer, String> {
 }

spring-batch-demo/src/main/java/com/stacktips/app/repository/CustomerRepository.java

@@ -8,8 +8,9 @@
 @UtilityClass
 public class DateUtils {
 
-    public static LocalDate convertDate(String subscriptionDate) {
-        DateTimeFormatter dateFormat = DateTimeFormatter.ofPattern("yyyy-MM-dd");
-        return LocalDate.parse(subscriptionDate, dateFormat);
+    public static LocalDate parseDate(String dateStr){
+        DateTimeFormatter formatter = DateTimeFormatter.ofPattern("yyyy-MM-dd");
+        return LocalDate.parse(dateStr, formatter);
     }
+
 }