FORMAT (under LOG for JGAS)

FORMAT is the JGAS configuration element that specifies the format and details included in a log message.

Syntax

<FORMAT Type="{TEXT|MULTILINE}">field-id-list[...]</FORMAT>
  1. The Type attribute can have one of two values:

    • TEXT, a log message is formatted without line breaks in a single line (new line characters are escaped).

      The default format for log file is TEXT, as set by the log.file.format resource.

    • MULTILINE format type handles formatting for multi-line output. It stops the logger from escaping new line characters, and provides for indentation, for example, when the DVM AUI tree is logged.

      The default for CONSOLE is MULTILINE as specified by the log.console.format resource.

  2. field-id-list, specifies one or more field identifiers that define the detail in the logged output. The fields are separated by spaces. The order of the fields determines the order of the log output. Valid field identifier types are shown in Table 1.
    Table 1. Log message field identifiers
    Type Description
    date Date of logging the event.
    time Time of logging the event.
    relative-time Time elapsed since the dispatcher started.
    thread-id Identifier of the thread logging the message.
    location Location of the logged message in the source code; the file name and line number where the event occurred.
    contexts Internal data representing the successive context the process went through to reach the logged event, for example, which VM, which HTTP request, etc. This data is formatted as type=value pairs separated by semicolons.
    event-type Type of event logged.
    event-params Event details or message to be logged. XML fragment representing the structured information attached to the event. This XML fragment will be on a single line, when the attribute Type is set to TEXT.
    Tip: If used, this field should be placed at the end as it can contain data with spaces.

Usage

You use this element to specify the format and details included in a log message.

Example

<FORMAT Type="TEXT">time event-type event-params</FORMAT>
<FORMAT Type="MULTILINE">date relative-time thread-id contexts
 event-type event-params</FORMAT>

Reading the logged output

When reading the content of logged output:
  • A log message ends with a line feed (LF) and carriage return (CR) character.
  • event-type values are enclosed in double quotes (").
  • event-params values may contain characters and spaces. Well-known non-printable characters are replaced by standard C escape sequences; other non-printable characters use a hexadecimal encoding.
  • All other field values do not contain spaces.
  • A missing value is replaced by a hyphen (-).
  • Single event-params values, such as raw text, have the following structure: Data Size=size Content=value, where size is the size of the value.
  • The event-params field output may contain:
    • a single line or escaped log message when the attribute Type is set to TEXT.
    • a multi-line log message when the attribute Type is set to MULTILINE.

Parent elements

This element is a child of the following elements: