de.unkrig.commons.util.logging.handler.AbstractStreamHandler Maven / Gradle / Ivy

Go to download

/*
 * de.unkrig.commons - A general-purpose Java class library
 *
 * Copyright (c) 2013, Arno Unkrig
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without modification, are permitted provided that the
 * following conditions are met:
 *
 *    1. Redistributions of source code must retain the above copyright notice, this list of conditions and the
 *       following disclaimer.
 *    2. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the
 *       following disclaimer in the documentation and/or other materials provided with the distribution.
 *    3. The name of the author may not be used to endorse or promote products derived from this software without
 *       specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
 * THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

package de.unkrig.commons.util.logging.handler;

import java.util.logging.Filter;
import java.util.logging.Formatter;
import java.util.logging.Level;
import java.util.logging.LogRecord;
import java.util.logging.SimpleFormatter;

import de.unkrig.commons.nullanalysis.NotNullByDefault;
import de.unkrig.commons.nullanalysis.Nullable;
import de.unkrig.commons.text.expression.EvaluationException;
import de.unkrig.commons.text.parser.ParseException;
import de.unkrig.commons.util.logging.LogUtil;

/**
 * Adds an 'autoFlush' feature to the {@link java.util.logging.StreamHandler}, and a one-arg constructor with a
 * variable property name prefix.
 */
@NotNullByDefault(false) public abstract
class AbstractStreamHandler extends java.util.logging.StreamHandler {

    private static final SimpleFormatter DEFAULT_FORMATTER = new SimpleFormatter();
    private boolean                      autoFlush;

    public
    AbstractStreamHandler() throws ParseException, EvaluationException {
        this(null);
    }

    /**
     * One-arg constructor to be used by derived classes.
     */
    public
    AbstractStreamHandler(@Nullable String propertyNamePrefix) throws ParseException, EvaluationException {

        if (propertyNamePrefix == null) propertyNamePrefix = this.getClass().getName();

        // We cannot be sure how the LogManager processes exceptions thrown by this constructor, so we print a stack
        // trace to STDERR before we rethrow the exception.
        // (The JRE default log manager prints a stack trace, too, so we'll see two.)
        try {
            this.init(
                LogUtil.getLoggingProperty(propertyNamePrefix + ".autoFlush", true),
                LogUtil.getLoggingProperty(propertyNamePrefix + ".level", Level.INFO),
                LogUtil.getLoggingProperty(propertyNamePrefix + ".filter", Filter.class, null),
                LogUtil.getLoggingProperty(
                    propertyNamePrefix + ".formatter",
                    Formatter.class,
                    AbstractStreamHandler.DEFAULT_FORMATTER
                ),
                LogUtil.getLoggingProperty(propertyNamePrefix + ".encoding", (String) null)
            );
        } catch (ParseException pe) {
            pe.printStackTrace();
            throw pe;
        } catch (EvaluationException ee) {
            ee.printStackTrace();
            throw ee;
        } catch (RuntimeException re) {
            re.printStackTrace();
            throw re;
        }
    }

    public
    AbstractStreamHandler(boolean autoFlush, Level level, Filter filter, Formatter formatter, String encoding) {
        this.init(autoFlush, level, filter, formatter, encoding);
    }

    @Override public synchronized void
    publish(LogRecord record) {
        super.publish(record);
        if (this.autoFlush) this.flush();
    }

    private void
    init(
        boolean             autoFlush,
        Level               level,
        @Nullable Filter    filter,
        @Nullable Formatter formatter,
        @Nullable String    encoding
    ) {

        this.autoFlush = autoFlush;

        // Re-configure the underlying 'java.util.logging.StreamHandler' with the CORRECT values.
        this.setLevel(level);
        this.setFilter(filter);
        this.setFormatter(formatter);
        try {
            this.setEncoding(encoding);
        } catch (Exception e) {
            try { this.setEncoding(null); } catch (Exception e2) {}
        }
    }
}