JSON to Tuple and Tuple to JSON Operator Sample

About This Sample

The sample application illustrate the use of the JSON to Tuple and Tuple to JSON operators. In this sample, the operator takes an input tuple and produces a JSON string, it then takes that string and produces a tuple. The sample is set up with a schema to try out various data types converting from tuples to JSON strings and back.

See the description of the operators' Properties views in Using the JSON to Tuple Operator and Using the Tuple to JSON Operator.

Importing This Sample into StreamBase Studio

In StreamBase Studio, import this sample with the following steps:

  • From the top-level menu, click FileLoad StreamBase Sample.

  • Type json to narrow the list of options.

  • Select JSONTuple from the Data Constructs and Operators category.

  • Click OK.

StreamBase Studio creates a project for the sample.

Running the Sample in StreamBase Studio

  1. In the Project Explorer, open the sample you just loaded.

  2. Open the src/main/eventflow folder.

  3. Open the package folder (most samples contain a single package folder. Open the top-level package folder if your sample contains more than one folder).

  4. Open the named application file and click the Run button. This opens the SB Test/Debug perspective and starts the application.

    If you see red marks, wait a moment for the project in Studio to load its features.

    If red marks do not resolve themselves in a moment, select the project and right-click MavenUpdate Project from the context menu.

  5. In the Manual Input view, select the TestInput stream and enter some values then click Send Data.

  6. In the Application Output view, observe a tuple dequeued on the JSONOutput and TupleOutput streams.

  7. Experiment by entering other values in the fields of the TestInput stream, clicking Send Data, and observing the resulting output tuples.

  8. When done, press F9 or click the Stop Running Application button.

Sample Location

When you load the sample into StreamBase Studio, Studio copies the sample project's files to your Studio workspace, which is normally part of your home directory, with full access rights.

Important

Load this sample in StreamBase Studio, and thereafter use the Studio workspace copy of the sample to run and test it, even when running from the command prompt.

Using the workspace copy of the sample avoids permission problems. The default workspace location for this sample is:

studio-workspace/sample_JSONTuple

See Default Installation Directories for the default location of studio-workspace on your system.