Deprecate JobOperator#start(String, String)

This method accepts job parameters as a string,
which can cause parsing issues.

Resolves #4304

Author: fmbenhassine

spring-batch-core/src/main/java/org/springframework/batch/core/launch/JobOperator.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2006-2022 the original author or authors.
+ * Copyright 2006-2023 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.
@@ -17,6 +17,7 @@
 
 import java.util.List;
 import java.util.Map;
+import java.util.Properties;
 import java.util.Set;
 
 import org.springframework.batch.core.Job;
@@ -111,10 +112,29 @@ default JobInstance getJobInstance(String jobName, JobParameters jobParameters)
 	 * parameters already exists
 	 * @throws JobParametersInvalidException thrown if any of the job parameters are
 	 * invalid.
+	 * @deprecated use {@link #start(String, Properties)} instead. Will be removed in
+	 * v5.2.
 	 */
+	@Deprecated(since = "5.0.1", forRemoval = true)
 	Long start(String jobName, String parameters)
 			throws NoSuchJobException, JobInstanceAlreadyExistsException, JobParametersInvalidException;
 
+	/**
+	 * Start a new instance of a job with the parameters specified.
+	 * @param jobName the name of the {@link Job} to launch
+	 * @param parameters the parameters to launch it with
+	 * @return the id of the {@link JobExecution} that is launched
+	 * @throws NoSuchJobException if there is no {@link Job} with the specified name
+	 * @throws JobInstanceAlreadyExistsException if a job instance with this name and
+	 * parameters already exists
+	 * @throws JobParametersInvalidException thrown if any of the job parameters are
+	 * invalid.
+	 */
+	default Long start(String jobName, Properties parameters)
+			throws NoSuchJobException, JobInstanceAlreadyExistsException, JobParametersInvalidException {
+		throw new UnsupportedOperationException();
+	}
+
 	/**
 	 * Restart a failed or stopped {@link JobExecution}. Fails with an exception if the id
 	 * provided does not exist or corresponds to a {@link JobInstance} that in normal
@@ -199,7 +219,7 @@ Long startNextInstance(String jobName) throws NoSuchJobException, JobParametersN
 
 	/**
 	 * List the available job names that can be launched with
-	 * {@link #start(String, String)}.
+	 * {@link #start(String, Properties)}.
 	 * @return a set of job names
 	 */
 	Set<String> getJobNames();

spring-batch-core/src/main/java/org/springframework/batch/core/launch/support/SimpleJobOperator.java

@@ -309,14 +309,27 @@ public Long restart(long executionId) throws JobInstanceAlreadyCompleteException
 	 * java.lang.String)
 	 */
 	@Override
+	@Deprecated(since = "5.0.1", forRemoval = true)
 	public Long start(String jobName, String parameters)
 			throws NoSuchJobException, JobInstanceAlreadyExistsException, JobParametersInvalidException {
+		Properties properties = PropertiesConverter.stringToProperties(parameters);
+		return start(jobName, properties);
+	}
+
+	/*
+	 * (non-Javadoc)
+	 *
+	 * @see org.springframework.batch.core.launch.JobOperator#start(java.lang.String,
+	 * java.util.Properties)
+	 */
+	@Override
+	public Long start(String jobName, Properties parameters)
+			throws NoSuchJobException, JobInstanceAlreadyExistsException, JobParametersInvalidException {
 		if (logger.isInfoEnabled()) {
 			logger.info("Checking status of job with name=" + jobName);
 		}
 
-		Properties properties = PropertiesConverter.stringToProperties(parameters);
-		JobParameters jobParameters = jobParametersConverter.getJobParameters(properties);
+		JobParameters jobParameters = jobParametersConverter.getJobParameters(parameters);
 
 		if (jobRepository.isJobInstanceExists(jobName, jobParameters)) {
 			throw new JobInstanceAlreadyExistsException(