Add hello world sample

Issue #4329

spring-batch-samples/src/main/java/org/springframework/batch/samples/helloworld/HelloWorldJobConfiguration.java

@@ -0,0 +1,49 @@
+/*
+ * Copyright 2023 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.springframework.batch.samples.helloworld;
+
+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.job.builder.JobBuilder;
+import org.springframework.batch.core.repository.JobRepository;
+import org.springframework.batch.core.step.builder.StepBuilder;
+import org.springframework.batch.repeat.RepeatStatus;
+import org.springframework.batch.samples.common.DataSourceConfiguration;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.context.annotation.Import;
+import org.springframework.jdbc.support.JdbcTransactionManager;
+
+@Configuration
+@EnableBatchProcessing
+@Import(DataSourceConfiguration.class)
+public class HelloWorldJobConfiguration {
+
+	@Bean
+	public Step step(JobRepository jobRepository, JdbcTransactionManager transactionManager) {
+		return new StepBuilder("step", jobRepository).tasklet((contribution, chunkContext) -> {
+			System.out.println("Hello world!");
+			return RepeatStatus.FINISHED;
+		}, transactionManager).build();
+	}
+
+	@Bean
+	public Job job(JobRepository jobRepository, Step step) {
+		return new JobBuilder("job", jobRepository).start(step).build();
+	}
+
+}

spring-batch-samples/src/main/java/org/springframework/batch/samples/helloworld/README.md

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+### Hello world sample
+
+## About
+
+This sample is a single-step job that prints "Hello world!" to the standard
+output. It shows the basic setup to configure and use Spring Batch.
+
+## Run the sample
+
+You can run the sample from the command line as following:
+
+```
+$>cd spring-batch-samples
+$>../mvnw -Dtest=HelloWorldJobFunctionalTests#testLaunchJob test
+```

spring-batch-samples/src/test/java/org/springframework/batch/samples/helloworld/HelloWorldJobFunctionalTests.java

@@ -0,0 +1,47 @@
+/*
+ * Copyright 2023 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.batch.samples.helloworld;
+
+import org.junit.jupiter.api.Test;
+
+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.launch.JobLauncher;
+import org.springframework.context.ApplicationContext;
+import org.springframework.context.annotation.AnnotationConfigApplicationContext;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+class HelloWorldJobFunctionalTests {
+
+	@Test
+	public void testLaunchJob() throws Exception {
+		// given
+		ApplicationContext context = new AnnotationConfigApplicationContext(HelloWorldJobConfiguration.class);
+		JobLauncher jobLauncher = context.getBean(JobLauncher.class);
+		Job job = context.getBean(Job.class);
+
+		// when
+		JobExecution jobExecution = jobLauncher.run(job, new JobParameters());
+
+		// then
+		assertEquals(BatchStatus.COMPLETED, jobExecution.getStatus());
+	}
+
+}