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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

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 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

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 *

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 */

package java.util.logging;

import java.io.*;

import java.time.ZoneId;

import java.time.ZonedDateTime;

import jdk.internal.logger.SurrogateLogger;

/**

 * Print a brief summary of the {@code LogRecord} in a human readable

 * format.  The summary will typically be 1 or 2 lines.

 *

 * <p>

 * <a name="formatting">

 * <b>Configuration:</b></a>

 * The {@code SimpleFormatter} is initialized with the

 * <a href="../Formatter.html#syntax">format string</a>

 * specified in the {@code java.util.logging.SimpleFormatter.format}

 * property to {@linkplain #format format} the log messages.

 * This property can be defined

 * in the {@linkplain LogManager#getProperty logging properties}

 * configuration file

 * or as a system property.  If this property is set in both

 * the logging properties and system properties,

 * the format string specified in the system property will be used.

 * If this property is not defined or the given format string

 * is {@linkplain java.util.IllegalFormatException illegal},

 * the default format is implementation-specific.

 *

 * @since 1.4

 * @see java.util.Formatter

 */

public class SimpleFormatter extends Formatter {

    // format string for printing the log record

    static String getLoggingProperty(String name) {

        return LogManager.getLogManager().getProperty(name);

    }

    private final String format =

        SurrogateLogger.getSimpleFormat(SimpleFormatter::getLoggingProperty);

    /**

     * Format the given LogRecord.

     * <p>

     * The formatting can be customized by specifying the

     * <a href="../Formatter.html#syntax">format string</a>

     * in the <a href="#formatting">

     * {@code java.util.logging.SimpleFormatter.format}</a> property.

     * The given {@code LogRecord} will be formatted as if by calling:

     * <pre>

     *    {@link String#format String.format}(format, date, source, logger, level, message, thrown);

     * </pre>

     * where the arguments are:<br>

     * <ol>

     * <li>{@code format} - the {@link java.util.Formatter

     *     java.util.Formatter} format string specified in the

     *     {@code java.util.logging.SimpleFormatter.format} property

     *     or the default format.</li>

     * <li>{@code date} - a {@link ZonedDateTime} object representing

     *     {@linkplain LogRecord#getInstant() event time} of the log record

     *      in the {@link ZoneId#systemDefault()} system time zone.</li>

     * <li>{@code source} - a string representing the caller, if available;

     *     otherwise, the logger's name.</li>

     * <li>{@code logger} - the logger's name.</li>

     * <li>{@code level} - the {@linkplain Level#getLocalizedName

     *     log level}.</li>

     * <li>{@code message} - the formatted log message

     *     returned from the {@link Formatter#formatMessage(LogRecord)}

     *     method.  It uses {@link java.text.MessageFormat java.text}

     *     formatting and does not use the {@code java.util.Formatter

     *     format} argument.</li>

     * <li>{@code thrown} - a string representing

     *     the {@linkplain LogRecord#getThrown throwable}

     *     associated with the log record and its backtrace

     *     beginning with a newline character, if any;

     *     otherwise, an empty string.</li>

     * </ol>

     *

     * <p>Some example formats:<br>

     * <ul>

     * <li> {@code java.util.logging.SimpleFormatter.format="%4$s: %5$s [%1$tc]%n"}

     *     <p>This prints 1 line with the log level ({@code 4$}),

     *     the log message ({@code 5$}) and the timestamp ({@code 1$}) in

     *     a square bracket.

     *     <pre>

     *     WARNING: warning message [Tue Mar 22 13:11:31 PDT 2011]

     *     </pre></li>

     * <li> {@code java.util.logging.SimpleFormatter.format="%1$tc %2$s%n%4$s: %5$s%6$s%n"}

     *     <p>This prints 2 lines where the first line includes

     *     the timestamp ({@code 1$}) and the source ({@code 2$});

     *     the second line includes the log level ({@code 4$}) and

     *     the log message ({@code 5$}) followed with the throwable

     *     and its backtrace ({@code 6$}), if any:

     *     <pre>

     *     Tue Mar 22 13:11:31 PDT 2011 MyClass fatal

     *     SEVERE: several message with an exception

     *     java.lang.IllegalArgumentException: invalid argument

     *             at MyClass.mash(MyClass.java:9)

     *             at MyClass.crunch(MyClass.java:6)

     *             at MyClass.main(MyClass.java:3)

     *     </pre></li>

     * <li> {@code java.util.logging.SimpleFormatter.format="%1$tb %1$td, %1$tY %1$tl:%1$tM:%1$tS %1$Tp %2$s%n%4$s: %5$s%n"}

     *      <p>This prints 2 lines similar to the example above

     *         with a different date/time formatting and does not print

     *         the throwable and its backtrace:

     *     <pre>

     *     Mar 22, 2011 1:11:31 PM MyClass fatal

     *     SEVERE: several message with an exception

     *     </pre></li>

     * <li> {@code java.util.logging.SimpleFormatter.format="%1$tb %1$td, %1$tY %1$tl:%1$tM:%1$tS.%1$tN %1$Tp %2$s%n%4$s: %5$s%6$s%n"}

     *      <p>Since JDK 9, {@code java.util.logging} uses {@link

     *         java.time.Clock#systemUTC() java.time} to create more precise time

     *         stamps.

     *         The format above can be used to add a {@code .%1$tN} to the

     *         date/time formatting so that nanoseconds will also be printed:

     *     <pre>

     *     Feb 06, 2015 5:33:10.279216000 PM example.Main main

     *     INFO: This is a test

     *     </pre></li>

     * </ul>

     * <p>This method can also be overridden in a subclass.

     * It is recommended to use the {@link Formatter#formatMessage}

     * convenience method to localize and format the message field.

     *

     * @param record the log record to be formatted.

     * @return a formatted log record

     */

    @Override

    public String format(LogRecord record) {

        ZonedDateTime zdt = ZonedDateTime.ofInstant(

                record.getInstant(), ZoneId.systemDefault());

        String source;

        if (record.getSourceClassName() != null) {

            source = record.getSourceClassName();

            if (record.getSourceMethodName() != null) {

               source += " " + record.getSourceMethodName();

            }

        } else {

            source = record.getLoggerName();

        }

        String message = formatMessage(record);

        String throwable = "";

        if (record.getThrown() != null) {

            StringWriter sw = new StringWriter();

            PrintWriter pw = new PrintWriter(sw);

            pw.println();

            record.getThrown().printStackTrace(pw);

            pw.close();

            throwable = sw.toString();

        }

        return String.format(format,

                             zdt,

                             source,

                             record.getLoggerName(),

                             record.getLevel().getLocalizedLevelName(),

                             message,

                             throwable);

    }

}