Add batch-5-to-6 module: Spring Batch 5.2 to 6.0 migration on Boot 3.5 to 4.1

Co-Authored-By: Claude Sonnet 5 <[email protected]>
Claude-Session: https://claude.ai/code/session_01Gth99spB1CzQmBFofXmU4Z

batch-5-to-6/legacy/pom.xml

@@ -0,0 +1,21 @@
+<?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 https://maven.apache.org/xsd/maven-4.0.0.xsd">
+  <modelVersion>4.0.0</modelVersion>
+  <parent>
+    <groupId>org.springframework.boot</groupId>
+    <artifactId>spring-boot-starter-parent</artifactId>
+    <version>3.5.16</version>
+    <relativePath/>
+  </parent>
+  <groupId>com.ankurm</groupId>
+  <artifactId>batch-legacy</artifactId>
+  <version>1.0.0</version>
+  <properties><java.version>21</java.version></properties>
+  <dependencies>
+    <dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-batch</artifactId></dependency>
+    <dependency><groupId>com.h2database</groupId><artifactId>h2</artifactId><scope>runtime</scope></dependency>
+    <dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-test</artifactId><scope>test</scope></dependency>
+    <dependency><groupId>org.springframework.batch</groupId><artifactId>spring-batch-test</artifactId><scope>test</scope></dependency>
+  </dependencies>
+  <build><plugins><plugin><groupId>org.springframework.boot</groupId><artifactId>spring-boot-maven-plugin</artifactId></plugin></plugins></build>
+</project>

batch-5-to-6/legacy/src/main/java/com/ankurm/batch/App.java

@@ -0,0 +1,14 @@
+package com.ankurm.batch;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+import org.springframework.context.ConfigurableApplicationContext;
+
+@SpringBootApplication
+public class App {
+    public static void main(String[] args) {
+        ConfigurableApplicationContext ctx = SpringApplication.run(App.class, args);
+        ctx.getBean(JobRunner.class).run();
+        ctx.close();
+    }
+}

batch-5-to-6/legacy/src/main/java/com/ankurm/batch/BatchConfig.java

@@ -0,0 +1,55 @@
+package com.ankurm.batch;
+
+import java.util.List;
+import org.springframework.batch.core.ChunkListener;
+import org.springframework.batch.core.Job;
+import org.springframework.batch.core.Step;
+import org.springframework.batch.core.job.builder.JobBuilder;
+import org.springframework.batch.core.repository.JobRepository;
+import org.springframework.batch.core.scope.context.ChunkContext;
+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.support.ListItemReader;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.transaction.PlatformTransactionManager;
+
+@Configuration
+public class BatchConfig {
+
+    @Bean
+    ItemReader<Integer> reader() {
+        return new ListItemReader<>(List.of(1, 2, 3, 4, 5, 6, 7));
+    }
+
+    @Bean
+    ItemWriter<String> writer() {
+        return chunk -> System.out.println("WRITE " + chunk.getItems());
+    }
+
+    @Bean
+    ChunkListener chunkListener() {
+        return new ChunkListener() {
+            @Override public void afterChunk(ChunkContext context) {
+                System.out.println("CHUNK DONE, read so far=" + context.getStepContext().getStepExecution().getReadCount());
+            }
+        };
+    }
+
+    @Bean
+    Step squareStep(JobRepository repo, PlatformTransactionManager tx, ChunkListener listener) {
+        return new StepBuilder("squareStep", repo)
+                .<Integer, String>chunk(3, tx)
+                .reader(reader())
+                .processor(i -> "sq" + (i * i))
+                .writer(writer())
+                .listener(listener)
+                .build();
+    }
+
+    @Bean
+    Job squareJob(JobRepository repo, Step squareStep) {
+        return new JobBuilder("squareJob", repo).start(squareStep).build();
+    }
+}

batch-5-to-6/legacy/src/main/java/com/ankurm/batch/JobRunner.java

@@ -0,0 +1,33 @@
+package com.ankurm.batch;
+
+import org.springframework.batch.core.BatchStatus;
+import org.springframework.batch.core.Job;
+import org.springframework.batch.core.JobExecution;
+import org.springframework.batch.core.JobParameters;
+import org.springframework.batch.core.JobParametersBuilder;
+import org.springframework.batch.core.explore.JobExplorer;
+import org.springframework.batch.core.launch.JobLauncher;
+import org.springframework.stereotype.Component;
+
+@Component
+public class JobRunner {
+    private final JobLauncher launcher;
+    private final JobExplorer explorer;
+    private final Job job;
+
+    public JobRunner(JobLauncher launcher, JobExplorer explorer, Job squareJob) {
+        this.launcher = launcher; this.explorer = explorer; this.job = squareJob;
+    }
+
+    public void run() {
+        try {
+            JobParameters params = new JobParametersBuilder().addLong("run.id", 1L).toJobParameters();
+            JobExecution exec = launcher.run(job, params);
+            System.out.println("STATUS " + exec.getStatus() + " exit=" + exec.getExitStatus().getExitCode());
+            System.out.println("INSTANCES " + explorer.getJobInstanceCount("squareJob"));
+            System.out.println("DONE " + (exec.getStatus() == BatchStatus.COMPLETED));
+        } catch (Exception e) {
+            throw new IllegalStateException(e);
+        }
+    }
+}

batch-5-to-6/legacy/src/main/resources/application.properties

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+spring.batch.job.enabled=false
+spring.datasource.url=jdbc:h2:mem:legacy;DB_CLOSE_DELAY=-1
+spring.batch.jdbc.initialize-schema=always

batch-5-to-6/legacy/src/test/java/com/ankurm/batch/JobTest.java

@@ -0,0 +1,23 @@
+package com.ankurm.batch;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+import org.junit.jupiter.api.Test;
+import org.springframework.batch.core.BatchStatus;
+import org.springframework.batch.core.JobExecution;
+import org.springframework.batch.test.JobLauncherTestUtils;
+import org.springframework.batch.test.context.SpringBatchTest;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.context.SpringBootTest;
+
+@SpringBootTest
+@SpringBatchTest
+class JobTest {
+    @Autowired JobLauncherTestUtils utils;
+
+    @Test
+    void jobCompletes() throws Exception {
+        JobExecution exec = utils.launchJob();
+        assertThat(exec.getStatus()).isEqualTo(BatchStatus.COMPLETED);
+    }
+}