Map Operator Sample

Contents

Running Map.sbapp in StreamBase Studio
Running Map.sbapp in Terminal Windows
Importing This Sample into StreamBase Studio
Sample Location

This sample uses a Map operator to accept tuples containing fields called Stockname, Symbol, Description, Volume, and Price. For each input tuple, a tuple containing only the fields called Symbol, Stockname, and Stockcost are output. This demonstrates one use of the Map operator to reorder and drop output fields, as well as calculate new output fields.

Running Map.sbapp in StreamBase Studio

  1. In the Package Explorer, double-click to open the Map.sbapp application. Make sure the application is the currently active tab in the EventFlow Editor.

  2. Click the Run button. This opens the SB Test/Debug perspective and starts the application.

  3. In the Application Output view, select the StockOut output stream. No output is displayed at this point, but the dequeuer is prepared to receive output. This view eventually shows the output of the application.

  4. In the Manual Input view, select the StockIn input stream

  5. Enter the following field values:

    Field Enter this value
    Symbol GE
    Name General Electric
    Description Makes everything from light bulbs to airplane engines.
    Volume 40487000
    Price 30.29

  6. Click Send Data, and a tuple arrives in the Application Output view. Select the new tuple and observe this data below the output stream table: 

    StockName=General Electric, StockSymbol=GE, StockCost=1.22635123E9

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

Running Map.sbapp in Terminal Windows

This section describes how to run the sample in UNIX terminal windows or Windows command prompt windows. On Windows, be sure to use the StreamBase Command Prompt from the Start menu as described in the Test/Debug Guide, not the default command prompt.

  1. Open three terminal windows on UNIX, or three StreamBase Command Prompts on Windows. In each window, navigate to the directory where the sample is installed, or to your workspace copy of the sample, as described above.

  2. In window 1, type: sbd Map.sbapp

    The window shows 

    notice[StreamBaseServer] listening on port 10000

  3. In window 2, type: sbc deq StockOut

    No output is displayed at this point, but the dequeuer is prepared to receive output. This window will eventually show the output of the application.

  4. In window 3, type: sbc enq StockIn

    The sbc command in window 3 now waits for keyboard input. Type:

    GE, General Electric, Light bulbs to airplan engines, 40487000, 30.29

    Observe this line in window 2:

    General Electric, GE, 1226351230

  5. In window 2, type: Ctrl+Z (Windows) or Ctrl+D (UNIX) to exit the sbc session.

  6. In window 3, type the following command to terminate the server and dequeuer:

    sbadmin shutdown

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Importing This Sample into StreamBase Studio

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

  • From the top menu, click File → Load StreamBase Sample.

  • Select operator from the Data Constructs and Operators category.

  • Click OK.

StreamBase Studio creates a single project for the operator samples.

Sample Location

By default, the sample files are installed in:

  • On Windows: C:\Program Files\StreamBase Systems\StreamBase.n.m\sample\operator

  • On UNIX: /opt/streambase/sample/operator

When you load the sample into StreamBase Studio, Studio copies the sample project's files to your Studio workspace. StreamBase Systems recommends that you use the workspace copy of the sample, especially on UNIX, where you may not have write access to /opt/streambase. In the default installation, the path to this sample in your Studio workspace is: 

UNIX:       
  ~/streambase-studio-n.m-workspace/sample_operator
Windows XP:
  C:\Documents and Settings\username\My Documents\StreamBase Studio n.m Workspace\
      sample_operator
Windows 7 and Windows Vista:
  C:\Users\username\Documents\StreamBase Studio n.m Workspace\
      sample_operator