public SparkAppJob sparkMaster(String sparkMaster){
		Assert.hasText(sparkMaster, "sparkMaster must not be null nor empty");
		this.sparkMaster = sparkMaster;
		return this;
	}
Sets The url of the spark master(spark://url:7077 or localhost[x]
@param sparkMaster the location of the spark master or localhost
@return current instance the job.
spring-xd-test-fixtures/src/main/java/org/springframework/xd/test/fixtures/SparkAppJob.java