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[JDK INTERNAL] The jdk.internal.logger package defines an internal provider whose default naive implementation is replaced by the java.logging module when the java.logging module is present. 

Default Implementation

 The JDK default implementation of the System.LoggerFinder will attempt to load an installed instance of the DefaultLoggerFinder defined in this package. When the java.util.logging package is present, this will usually resolve to an instance of LoggingProviderImpl - which provides an implementation of the Logger whose backend is a java.util.logging.Logger. Configuration can thus be performed by direct access to the regular java.util.logging APIs, using java.util.logging.Logger and LogManager to access and configure the backend Loggers. 
 If however java.util.logging is not linked with the application, then the default implementation will return a simple logger that will print out all log messages of INFO level and above to the console (System.err), as implemented by the base DefaultLoggerFinder class. 

Message Levels and Mapping to java.util.logging

 The LoggerFinder class documentation describe how System.Logger levels are mapped to JUL levels when 
java.util.logging is the backend. 
See Also:
Since:9
/**
 * <b>[JDK INTERNAL]</b>
 * The {@code jdk.internal.logger} package defines an internal provider
 * whose default naive implementation is replaced by the {@code java.logging}
 * module when the {@code java.logging} module is present.
 * <p>
 * <b>Default Implementation</b>
 * <p>
 * The JDK default implementation of the System.LoggerFinder will attempt to
 * load an installed instance of the {@link jdk.internal.logger.DefaultLoggerFinder}
 * defined in this package.
 * When the {@code java.util.logging} package is present, this will usually
 * resolve to an instance of {@link sun.util.logging.internal.LoggingProviderImpl} -
 * which provides an implementation of the Logger whose backend is a
 * {@link java.util.logging.Logger java.util.logging.Logger}.
 * Configuration can thus be performed by direct access to the regular
 * {@code java.util.logging} APIs,
 * using {@link java.util.logging.Logger java.util.logging.Logger} and
 * {@link java.util.logging.LogManager} to access and configure the backend
 * Loggers.
 * <br>
 * If however {@code java.util.logging} is not linked with the application, then
 * the default implementation will return a simple logger that will print out
 * all log messages of INFO level and above to the console ({@code System.err}),
 * as implemented by the base {@link jdk.internal.logger.DefaultLoggerFinder} class.
 * <p>
 * <b>Message Levels and Mapping to java.util.logging</b>
 * <p>
 * The {@link java.lang.System.LoggerFinder} class documentation describe how
 * {@linkplain java.lang.System.Logger.Level System.Logger levels} are mapped
 * to {@linkplain java.util.logging.Level JUL levels} when {@code
 * java.util.logging} is the backend.
 *
 * @see jdk.internal.logger.DefaultLoggerFinder
 * @see sun.util.logging.internal.LoggingProviderImpl
 * @see java.lang.System.LoggerFinder
 * @see java.lang.System.Logger
 * @see sun.util.logging.PlatformLogger.Bridge
 * @see sun.util.logging.internal
 *
 * @since 9
 */
package jdk.internal.logger;