In a DataStream job, you can obtain custom parameters from the main function as needed.

Method to obtain and set custom parameters

To obtain a custom parameter from the main function, define the custom parameter in the format of paramName=paramValue in a DataStream job.
  • paramName: the name of the custom parameter.
  • paramValue: the value of the custom parameter.
Note You can define multiple custom parameters in a DataStream job.

Example of obtaining and setting custom parameters

Note After you set on the development page, you can use the following code to assign the jobnametest string to the jobName variable.
import java.nio.charset.StandardCharsets;
import java.nio.file.Files;
import java.nio.file.Paths;
import java.util.Properties;

public class getParameterExample {
    public static void main(String[] args)throws Exception {
        final String jobName;
        final ParameterTool params = ParameterTool.fromArgs(args);

        /*You must enter configFile to read parameters in configFile. */
        String configFilePath = params.get("configFile");

        /*Create a Properties object to save parameter values that you set in the system. */
        Properties properties = new Properties();

        /*Load parameter values that you set in the system to the Properties object. */
        properties.load(new StringReader(new String(Files.readAllBytes(Paths.get(configFilePath)), StandardCharsets.UTF_8)));

        /*Obtain the jobName parameter. */
        jobName = (String) properties.get("");
Note The preceding example only demonstrates how to obtain and use custom parameters in the main function. To use custom parameters in a Flink operator, you must add the following code to the preceding code to convert custom parameters to global job parameters. Then, you can obtain the corresponding parameters in a Flink operator by using the getproperty method of the Configuration class.