Network Deployment (Distributed operating systems), v8.0 > Reference > Log and trace file descriptions
JVM log interpretation
View the JVM log files to determine problems within application environments.
The JVM logs contain print data written by applications. The application can write this data directly in the form of .print(), System.err.print(), or other method calls. The application can also write data indirectly by calling a JVM function, such as an Exception.printStackTrace(). In addition, the JVM log contains system messages written by the WAS.
We can format application data to look like WAS system messages by using the Installed Application Output field of the JVM Logs properties panel, or as plain text with no additional formatting. WAS system messages are always formatted. Depending on how the JVM log is configured, formatted messages can be written to the JVM logs in either basic or advanced format.
Message formats
Formatted messages are written to the JVM logs in one of two formats:
Basic Format
The format used in earlier versions of WAS.
Advanced Format
Extends the basic format by adding information about an event, when possible.
Basic and advanced format fields
Basic and Advanced Formats use many of the same fields and formatting techniques. The various fields that may be found in these formats follow:
TimeStamp
The timestamp is formatted using the locale of the process where it is formatted. It includes a fully qualified date (for example YYMMDD), 24 hour time with millisecond precision and a time zone.
ThreadId
An 8 character hexadecimal value generated from the hash code of the thread that issued the message.
ThreadName
The name of the Java thread that issued the message or trace event.
ShortName
The abbreviated name of the logging component that issued the message or trace event. This is typically the class name for WAS internal components, but can be some other identifier for user applications.
LongName
The full name of the logging component that issued the message or trace event. This is typically the fully qualified class name for WAS internal components, but can be some other identifier for user applications.
EventType
A one character field that indicates the type of the message or trace event. Message types are in upper case. Possible values include:
F
A Fatal message.
E
An Error message.
W
A Warning message.
A
An Audit message.
I
An Informational message.
C
An Configuration message.
D
A Detail message.
O
A message that was written directly to by the user application or internal components.
R
A message that was written directly to System.err by the user application or internal components.
Z
A placeholder to indicate the type was not recognized.
ClassName
The class that issued the message or trace event.
MethodName
The method that issued the message or trace event.
Organization
The organization that owns the application that issued the message or trace event.
Product
The product that issued the message or trace event.
Component
The component within the product that issued the message or trace event.
Basic format
Message events displayed in basic format use the following format. The notation <name> indicates mandatory fields that will always appear in the basic format message. The notation [name] indicates optional or conditional fields that will be included if they can be determined.
<timestamp> <threadId> <shortName> <eventType>[className][methodName] <message>
Advanced format
Message events displayed in advanced format use the following format. The notation <name> is used to indicate mandatory fields that will always appear in the advanced format for message entries. The notation [name] is used to indicate optional or conditional fields that will be included if they can be determined.
<timestamp> <threadId> <eventType> <UOW> <source=longName>[className] [methodName] <Organization> <Product> <Component> [thread=threadName] <message>
Configure the JVM logs
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