Analyze JVM Logs

SystemOut.log and SystemErr.log files are text files so you can view them using simple text editor.
The Application server writes formatted messages to the SystemOut.log file and this is how a sample log message looks like

[7/2/09 9:12:22:645 PDT] 00000017 ApplicationMg A WSVR0221I: Application started: SchedulerCalendars

Each entry can be deciphered as follows

  • Time Stamp: The first part of the log message in sample code is [7/2/09 9:12:22:645 PDT]. It is the time stamp when the message was written. The time stamp is formatted using the locale of the process and it is 24 hour time stamp with milli-second precision

  • Thread ID: The next part in the log message is 00000017, which represents the thread id. The thread ID is an eight-character hexadecimal value that is generated from the hash code of the thread that issued the message

  • Short name: The short name is the abbreviated name of the component that issued the message. This name is typically the class name of a WAS component and would be some other identifier for the application. In our sample the ApplicationMg is component name

  • Event Type: The event type is a one character field that indicates the type of the message. The possible values are

    • F- Fatal message

    • E- Error message

    • W- Warning message

    • A- Audit message

    • I- Informational message

    • C- Configuration message

    • D- detail message

    • O- Messages that are written directly to System.out by an application or server component

    • R- Messages that are written directly to System.err by the user application or internal component.

    • Z- Place holder to indicate type was not recognized


    In my sample message A indicates this is audit message

  • Message identifier: The message identifier is a string that is nine characters in length and is in the form CCCC1234X. THe first four characters indicate the WAS component that issues the message. The next four characters indicate the specific message that component is issuing. The last character indicates the severity of the message. Its value is either I- informational, W- Warning or E error. You can find description of all identifiers in the WAS Information center. If your looking at the message in the Rational Application developer console, then each of these message identifier would be displayed as link. Clicking on the link would give details for the message identifier like this.


    If not you can get similar details about the message identifier by using Log Analyzer.



  • Message: The message is the data that is logged to the SystemOut.log by the component

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