Remove DisposableBean implements from SimpleJobService (#6035)

This can be removed because SCDF does not manage internal jobs,
but rather launches boot apps that use Spring Batch

resolves #6034

spring-cloud-dataflow-server-core/src/main/java/org/springframework/cloud/dataflow/server/batch/SimpleJobService.java

@@ -15,41 +15,29 @@
  */
 package org.springframework.cloud.dataflow.server.batch;
 
-import java.time.LocalDateTime;
-import java.util.ArrayList;
 import java.util.Collection;
-import java.util.Collections;
 import java.util.Date;
-import java.util.Iterator;
-import java.util.LinkedHashSet;
 import java.util.List;
 import java.util.Map;
 import java.util.Objects;
 import java.util.Set;
 
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
-
 import org.springframework.batch.core.BatchStatus;
 import org.springframework.batch.core.JobExecution;
 import org.springframework.batch.core.JobInstance;
 import org.springframework.batch.core.JobParameters;
-import org.springframework.batch.core.JobParametersInvalidException;
 import org.springframework.batch.core.StepExecution;
 import org.springframework.batch.core.launch.JobExecutionNotRunningException;
-import org.springframework.batch.core.launch.JobInstanceAlreadyExistsException;
 import org.springframework.batch.core.launch.JobOperator;
 import org.springframework.batch.core.launch.NoSuchJobException;
 import org.springframework.batch.core.launch.NoSuchJobExecutionException;
 import org.springframework.batch.core.launch.NoSuchJobInstanceException;
-import org.springframework.batch.core.repository.JobExecutionAlreadyRunningException;
 import org.springframework.batch.core.repository.JobRepository;
 import org.springframework.batch.core.repository.dao.ExecutionContextDao;
 import org.springframework.batch.core.step.NoSuchStepException;
-import org.springframework.beans.factory.DisposableBean;
-import org.springframework.scheduling.annotation.Scheduled;
 import org.springframework.util.Assert;
-import org.springframework.util.CollectionUtils;
 import org.springframework.util.StringUtils;
 
 /**
@@ -61,7 +49,7 @@
  * @author Glenn Renfro
  * @author Corneil du Plessis
  */
-public class SimpleJobService implements JobService, DisposableBean {
+public class SimpleJobService implements JobService {
 
 	private static final Logger logger = LoggerFactory.getLogger(SimpleJobService.class);
 
@@ -78,8 +66,6 @@ public class SimpleJobService implements JobService, DisposableBean {
 
 	private final ExecutionContextDao executionContextDao;
 
-	private Collection<JobExecution> activeExecutions = Collections.synchronizedList(new ArrayList<JobExecution>());
-
 	private JobOperator jobOperator;
 
 
@@ -339,62 +325,4 @@ private void checkJobExists(String jobName) throws NoSuchJobException {
 			throw new NoSuchJobException("No Job with that name either current or historic: [" + jobName + "]");
 		}
 	}
-
-	/**
-	 * Stop all the active jobs and wait for them (up to a time out) to finish processing.
-	 */
-	@Override
-	public void destroy() throws Exception {
-
-		Exception firstException = null;
-
-		for (JobExecution jobExecution : activeExecutions) {
-			try {
-				if (jobExecution.isRunning()) {
-					stop(jobExecution.getId());
-				}
-			} catch (JobExecutionNotRunningException e) {
-				logger.info("JobExecution is not running so it cannot be stopped");
-			} catch (Exception e) {
-				logger.error("Unexpected exception stopping JobExecution", e);
-				if (firstException == null) {
-					firstException = e;
-				}
-			}
-		}
-
-		int count = 0;
-		int maxCount = (shutdownTimeout + 1000) / 1000;
-		while (!activeExecutions.isEmpty() && ++count < maxCount) {
-			logger.error("Waiting for " + activeExecutions.size() + " active executions to complete");
-			removeInactiveExecutions();
-			Thread.sleep(1000L);
-		}
-
-		if (firstException != null) {
-			throw firstException;
-		}
-
-	}
-
-	/**
-	 * Check all the active executions and see if they are still actually running. Remove the
-	 * ones that have completed.
-	 */
-	@Scheduled(fixedDelay = 60000)
-	public void removeInactiveExecutions() {
-
-		for (Iterator<JobExecution> iterator = activeExecutions.iterator(); iterator.hasNext(); ) {
-			JobExecution jobExecution = iterator.next();
-			try {
-				jobExecution = getJobExecution(jobExecution.getId());
-			} catch (NoSuchJobExecutionException e) {
-				logger.error("Unexpected exception loading JobExecution", e);
-			}
-			if (!jobExecution.isRunning()) {
-				iterator.remove();
-			}
-		}
-
-	}
 }