Adding PerformanceMonitor Methods to your Code

Adding PerformanceMonitor Methods to your Code

To enable the Performance Monitor to monitor a section of your Java code:

1. Import the atg.service.perfmonitor.* package.

2. Declare an opName parameter to label the section of the code. This parameter is displayed in the Performance Monitor page under the Operation heading.

3. (Optional) Declare a parameter name if you want to gather data on individual executions of an operation.

4. Call the startOperation method at the beginning of the operation whose performance you want to be able to measure.

5. Call the endOperation method at the end of the operation whose performance you want to be able to measure.

6. Optionally, call the cancelOperation method if an exception occurs. This causes the results of the    current execution to be ignored.

For details about the Performance Monitor’s startOperation, endOperation, and cancelOperation methods, see Methods for Storing Performance Data.

For example:

String opName = "render jsp";

String parameter = "foo.jsp";

boolean exception = false;

PerformanceMonitor.startOperation(opName, parameter);

try {

  ... code to actually render foo.jsp

} catch (Exception e) {

  PerformanceMonitor.cancelOperation(opName, parameter);

  exception = true;

} finally {

  if (! exception)

    PerformanceMonitor.endOperation(opName, parameter);

}

These methods can be nested with different or the same opNames.

For example:

private final String RENDER_JSP = "Render JSP page";

private final String EXECUTE_SQL = "Execute SQL Query";

private String mPageName = "page.jsp";

private String mSQLQuery = "select * from table";

PerformanceMonitor.startOperation(RENDER_JSP, mPageName);

... source code to start render

  PerformanceMonitor.startOperation(EXECUTE_SQL, mSQLQuery);

  ... source code to read from table 1 in database

    PerformanceMonitor.startOperation(EXECUTE_SQL);

    ... source code to read from database

    PerformanceMonitor.endOperation(EXECUTE_SQL);

  ... more source code to read from table 1 in database

  PerformanceMonitor.endOperation(EXECUTE_SQL, mSQLQuery);

... more source code to finish render

PerformanceMonitor.endOperation(RENDER_JSP, mPageName);

Note that the calls to startOperation are nested within other calls to startOperation. You must place the endOperation and cancelOperation calls in the code in opposite order that the startOperation calls were placed. If this requirement is not followed, then the endOperation or cancelOperation call throws a PerfStackMismatchException. This exception tells you that the calls to endOperation are not being matched up. Either they were not called in the correct order or the arguments were not exactly the same as those that were passed into the methods.

To ensure that endOperation is always called, wrap the Performance Monitor methods in a try ... finally block, as in this example:

boolean exception = false;

try {

  PerformanceMonitor.startOperation(OP_NAME);

  performOperation (pParameter);

} catch (Exception e) {

  PerformanceMonitor.cancelOperation(OP_NAME);

  exception = true;

} finally {

  try {

    if (!exception)

      PerformanceMonitor.endOperation(OP_NAME);

  } catch (PerfStackMismatchException e) {

    System.out.println(e);

  }

}