org.kiwiproject.retry.RetryLogger Maven / Gradle / Ivy

package org.kiwiproject.retry;

import static com.google.common.base.Preconditions.checkArgument;

import lombok.experimental.UtilityClass;
import org.slf4j.Logger;
import org.slf4j.event.Level;

/**
 * Package-private helper class to log attempts at different SLF4J logging levels (since SLF4J 1.7.x does not
 * provide any log methods that accept a {@link Level} object, we unfortunately have to resort to this instead).
 *
 * @see Logger SLFJ Logger
 * @see Level SLF4J Level
 */
@UtilityClass
class RetryLogger {

    /**
     * Log an attempt for the current attempt number. First attempts are always logged at TRACE level.
     *
     * @param logger         the Logger to use
     * @param level          the Level to log at for retry attempts
     * @param currentAttempt the current attempt number (starting at 1)
     * @param message        the message or message template
     * @param args           the optional arguments if the message is a template
     */
    static void logAttempt(Logger logger,
                           Level level,
                           long currentAttempt,
                           String message,
                           Object... args) {

        checkArgument(currentAttempt > 0, "currentAttempt must be a positive integer");

        // If this is the first attempt, just log the traffic at trace level regardless of the log level argument
        if (currentAttempt == 1) {
            logger.trace(message, args);
            return;
        }

        // Otherwise, log it at the appropriate level
        logAttempt(logger, level, message, args);
    }

    /**
     * Log an attempt at the specified {@link Level}.
     *
     * @param logger  the Logger to use
     * @param level   the Level to log at for retry attempts
     * @param message the message or message template
     * @param args    the optional arguments if the message is a template
     */
    static void logAttempt(Logger logger, Level level, String message, Object... args) {
        switch (level) {
            case DEBUG:
                logger.debug(message, args);
                break;

            case INFO:
                logger.info(message, args);
                break;

            case WARN:
                logger.warn(message, args);
                break;

            case ERROR:
                logger.error(message, args);
                break;

            case TRACE:
            default:
                // NOTE: Intentional fall-through from TRACE. Whenever move to JDK 14+ can use enhanced switch
                //  when we won't need default since we'll be exhaustive on all Level values
                logger.trace(message, args);
                break;
        }
    }
}