#11 spring batch: JobExecutionDecider

spring-batch/basic/src/main/java/io/springbatch/basic/flow/CustomDecider.java

@@ -0,0 +1,22 @@
+package io.springbatch.basic.flow;
+
+import org.springframework.batch.core.JobExecution;
+import org.springframework.batch.core.StepExecution;
+import org.springframework.batch.core.job.flow.FlowExecutionStatus;
+import org.springframework.batch.core.job.flow.JobExecutionDecider;
+
+import java.util.Random;
+
+public class CustomDecider implements JobExecutionDecider {
+
+
+    @Override
+    public FlowExecutionStatus decide(JobExecution jobExecution, StepExecution stepExecution) {
+
+        Random random = new Random();
+        int count = random.nextInt(100);
+
+        return count % 2 == 0 ?
+                new FlowExecutionStatus("EVEN") : new FlowExecutionStatus("ODD");
+    }
+}

spring-batch/basic/src/main/java/io/springbatch/basic/flow/CustomExitStatusConfiguration.java

@@ -11,7 +11,7 @@ import org.springframework.batch.repeat.RepeatStatus;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
 
-@Configuration
+//@Configuration
 @RequiredArgsConstructor
 public class CustomExitStatusConfiguration {
 

spring-batch/basic/src/main/java/io/springbatch/basic/flow/JobExecutionDeciderConfiguration.java

@@ -0,0 +1,76 @@
+package io.springbatch.basic.flow;
+
+import lombok.RequiredArgsConstructor;
+import org.springframework.batch.core.Job;
+import org.springframework.batch.core.Step;
+import org.springframework.batch.core.configuration.annotation.JobBuilderFactory;
+import org.springframework.batch.core.configuration.annotation.StepBuilderFactory;
+import org.springframework.batch.core.job.flow.JobExecutionDecider;
+import org.springframework.batch.core.launch.support.RunIdIncrementer;
+import org.springframework.batch.repeat.RepeatStatus;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+
+@Configuration
+@RequiredArgsConstructor
+public class JobExecutionDeciderConfiguration {
+
+    private final JobBuilderFactory jobBuilderFactory;
+    private final StepBuilderFactory stepBuilderFactory;
+
+    /*
+        JobExecutionDecider
+
+        - ExitStatus 를 조작하거나 StepExecutionListener 를 등록할 필요없이 Transition 처리를 위한 전용 클래스
+        - Step 과 Transition 역할을 명확히 분리해서 설정 가능
+        - Step 의  ExitStatus 가 아닌 JobExecutionDecider 의 FlowExecutionStatus 상태값을 새롭게 설정해서 반환
+
+     */
+    @Bean
+    public Job batchJob() {
+        return jobBuilderFactory.get("batchJob")
+                .incrementer(new RunIdIncrementer())
+                .start(step())
+                .next(decider())
+                .from(decider()).on("ODD").to(oddStep())
+                .from(decider()).on("EVEN").to(evenStep())
+                .end()
+                .build();
+    }
+
+    @Bean
+    public JobExecutionDecider decider() {
+        return new CustomDecider();
+    }
+
+    @Bean
+    public Step step() {
+        return stepBuilderFactory.get("step")
+                .tasklet((contribution, chunkContext) -> {
+                    System.out.println(">> This is the start tasklet");
+                    return RepeatStatus.FINISHED;
+                })
+                .build();
+    }
+
+    @Bean
+    public Step evenStep() {
+        return stepBuilderFactory.get("evenStep")
+                .tasklet((contribution, chunkContext) -> {
+                    System.out.println(">> EvenStep was executed");
+                    return RepeatStatus.FINISHED;
+                })
+                .build();
+    }
+
+    @Bean
+    public Step oddStep() {
+        return stepBuilderFactory.get("oddStep")
+                .tasklet((contribution, chunkContext) -> {
+                    System.out.println(">> OddStep was executed");
+                    return RepeatStatus.FINISHED;
+                })
+                .build();
+    }
+
+}