Class ExistsRule

java.lang.Object
org.apache.log4j.rule.AbstractRule
org.apache.log4j.rule.ExistsRule
All Implemented Interfaces:
Serializable, Rule

public class ExistsRule extends AbstractRule
A Rule class implementing a not null (and not empty string) check.
See Also:
  • Field Details

  • Constructor Details

    • ExistsRule

      private ExistsRule(String fld)
      Create new instance.
      Parameters:
      fld - field name.
  • Method Details

    • getRule

      public static Rule getRule(String field)
      Get an instance of ExistsRule.
      Parameters:
      field - field.
      Returns:
      instance of ExistsRule.
    • getRule

      public static Rule getRule(Stack stack)
      Create an instance of ExistsRule using the top name on the stack.
      Parameters:
      stack - stack
      Returns:
      instance of ExistsRule.
    • evaluate

      public boolean evaluate(org.apache.log4j.spi.LoggingEvent event, Map matches)
      Returns true if this implementation of the rule accepts the LoggingEvent, or false if not.

      What True/False means can be client-specific.

      Parameters:
      event - LoggingEvent this instance will evaluate
      matches - a Map of event field keys to Sets of matching strings (may be null) which will be updated during execution of this method to include field and string matches based on the rule evaluation results
      Returns:
      true if this Rule instance accepts the event, otherwise false.