PIOT-GDA-02-003: Connect SystemPerformanceManager to GatewayDeviceApp

[labbenchstudios]

Description

• Connect SystemPerformanceManager to GatewayDeviceApp so it can be started and stopped with the application. This work should be implemented within the GatewayDeviceApp class.

Review the README

• Please see README.md for further information on, and use of, this content.
• License for embedded documentation and source codes: PIOT-DOC-LIC

Estimated effort may vary greatly

• The estimated level of effort for this exercise shown in the 'Estimate' section below is a very rough approximation. The actual level of effort may vary greatly depending on your development and test environment, experience with the requisite technologies, and many other factors.

Actions

NOTE: The implementation examples depicted here are only one way to implement the requirements listed. Your own implementation may vary of course.

• Be sure to import the SystemPerformanceManager class. For example:

  import programmingtheiot.gda.system.SystemPerformanceManager;

• Create a class-scoped variable named sysPerfManager.
• Create an instance of SystemPerformanceManager within the GatewayDeviceApp constructor called this.sysPerfManager.

  
  private SystemPerformanceManager sysPerfMgr = null;

public GatewayDeviceApp(String[] args) { super();

_Logger.info("Initializing GDA...");

this.sysPerfMgr = new SystemPerformanceManager();

}

- Edit the `startApp()` method: Add a call to `sysPerfManager.startManager()`.
- Edit the `stopApp()` method: Add a call to `sysPerfManager.stopManager()`.
```java
public void startApp()
{
    _Logger.info("Starting GDA...");

    try {
        if (this.sysPerfMgr.startManager()) {
            _Logger.info("GDA started successfully.");
        } else {
            _Logger.warning("Failed to start system performance manager!");

            stopApp(-1);
        }
    } catch (Exception e) {
        _Logger.log(Level.SEVERE, "Failed to start GDA. Exiting.", e);

        stopApp(-1);
    }
}

public void stopApp(int code)
{
    _Logger.info("Stopping GDA...");

    try {
        if (this.sysPerfMgr.stopManager()) {
            _Logger.log(Level.INFO, "GDA stopped successfully with exit code {0}.", code);
        } else {
            _Logger.warning("Failed to stop system performance manager!");
        }
    } catch (Exception e) {
        _Logger.log(Level.SEVERE, "Failed to cleanly stop GDA. Exiting.", e);
    }

    System.exit(code);
}

NOTE: Additional functionality will be added in a later chapter.

Estimate

• Small

Tests

• Integration tests (in ./src/test/java/programmingtheiot/part01/integration)
  • Run GatewayDeviceAppTest. The log output should look similar to the following:

    Jul 19, 2020 1:01:38 PM programmingtheiot.gda.app.GatewayDeviceApp <init>
    INFO: Initializing GDA...
    Jul 19, 2020 1:01:38 PM programmingtheiot.gda.app.GatewayDeviceApp parseArgs
    INFO: No command line args to parse.
    Jul 19, 2020 1:01:38 PM programmingtheiot.gda.app.GatewayDeviceApp initConfig
    INFO: Attempting to load configuration: Default.
    Jul 19, 2020 1:01:38 PM programmingtheiot.gda.app.GatewayDeviceApp startApp
    INFO: Starting GDA...
    Jul 19, 2020 1:01:38 PM programmingtheiot.gda.system.SystemPerformanceManager startManager
    INFO: SytemPerformanceManager is starting...
    Jul 19, 2020 1:01:38 PM programmingtheiot.gda.app.GatewayDeviceApp startApp
    INFO: GDA started successfully.
    Jul 19, 2020 1:01:38 PM programmingtheiot.gda.app.GatewayDeviceApp stopApp
    INFO: Stopping GDA...
    Jul 19, 2020 1:01:38 PM programmingtheiot.gda.system.SystemPerformanceManager stopManager
    INFO: SytemPerformanceManager is stopped.
    Jul 19, 2020 1:01:38 PM programmingtheiot.gda.app.GatewayDeviceApp stopApp
    INFO: GDA stopped successfully with exit code 0.

[dbeavers]

Added: import programmingtheiot.gda.system.SystemPerformanceManager;

[labbenchstudios]

Added clarification.

[htayyar]

Parsing of argument is missing. Should be as follows

public GatewayDeviceApp(String[] args) { super();

    _Logger.info("Initializing GDA...");

    parseArgs(args);

    this.sysPerfMgr = new SystemPerformanceManager();
}

[labbenchstudios]

Correct. Currently, command line arg parsing is an optional activity and not implemented as part of the Lab Module exercises. For those who'd like to incorporate this, please feel free to do so in your repo!