co.mindus.ip2location

Interface IEventLogger

Functional Interface:

This is a functional interface and can therefore be used as the assignment target for a lambda expression or method reference.

@FunctionalInterface
public interface IEventLogger

Event logger interface for IP2Location components integrated with the Application Server and its logging framework.

This functional interface provides a bridge between IP2Location's internal logging and your application's logging framework. Implementations receive structured log events with severity level, message, and optional exception.

Event Types

Constant	Value	Usage
INFO	0	Normal operations: startup, successful downloads
WARNING	1	Recoverable issues: retry attempts, missing files
ERROR	2	Serious failures: I/O errors, initialization failures

Thread Safety

Implementations must be thread-safe as log events may be generated from multiple threads simultaneously (update scheduler, lookup threads, etc.).

Author:

Christopher Mindus

See Also:

IP2LocationService.Builder.logger(IEventLogger), IP2LocationManager.setLogger(IEventLogger)

Field Summary

Fields

Modifier and Type	Field and Description
static int	ERROR Log level for error messages.
static int	INFO Log level for informational messages.
static int	WARNING Log level for warning messages.

Method Summary

Modifier and Type	Method and Description
static IEventLogger	consoleLogger() Returns a logger that writes to the console (System.out/System.err).
default void	logEvent(Class<?> callerClass, int type, String message) Logs an event without an exception.
void	logEvent(Class<?> callerClass, int type, String message, Throwable ex) Logs an event with an optional exception.
static IEventLogger	nullLogger() Returns a logger that discards all messages.

Field Detail

INFO

static final int INFO

Log level for informational messages.

Used for normal operational messages such as:

• Service startup and shutdown
• Successful database downloads
• Database reloads
• Configuration changes

See Also:

Constant Field Values

WARNING

static final int WARNING

Log level for warning messages.

Used for potentially problematic situations that don't prevent operation:

• Download retry attempts
• Missing database files (will be downloaded)
• Stale database detection
• Proxy configuration issues

See Also:

Constant Field Values

ERROR

static final int ERROR

Log level for error messages.

Used for serious failures that may affect functionality:

• Database load failures
• Persistent download failures
• I/O errors during lookup
• Initialization failures

See Also:

Constant Field Values

Method Detail

logEvent

default void logEvent(Class<?> callerClass,
                      int type,
                      String message)

Logs an event without an exception.

This is a convenience method that delegates to logEvent(Class, int, String, Throwable) with a null exception.*

Parameters:

callerClass - The class that generated the log event

type - The event type: INFO, WARNING, or ERROR

message - The log message (never null)

logEvent

void logEvent(Class<?> callerClass,
              int type,
              String message,
              Throwable ex)

Logs an event with an optional exception.

This is the primary logging method that implementations must provide. It receives all information needed to produce a complete log entry.

Parameters:

callerClass - The class that generated the log event (never null). Useful for creating class-specific loggers.

type - The event type: INFO, WARNING, or ERROR. Other values should be treated as INFO.

message - The log message (never null). May contain formatting but no placeholders (already formatted).

ex - An exception associated with the event, or null if none. When present, implementations should include the stack trace at WARNING and ERROR levels.

consoleLogger

static IEventLogger consoleLogger()

Returns a logger that writes to the console (System.out/System.err).

INFO and WARNING messages go to System.out, ERROR messages to System.err. Stack traces are printed for WARNING and ERROR events with exceptions.

Returns:

A console-based logger implementation.

nullLogger

static IEventLogger nullLogger()

Returns a logger that discards all messages.

Useful for testing or when logging is handled externally.

Returns:

A no-op logger that ignores all events.