Apache Log4j Core Implementation provides the functional components of the logging system. Users are free to create their own plugins and include them in the logging configuration. Apache Log4j Core is a required module to use Apache Log4j.

Bytecode (Java 8) for Apache Log4j Core Implementation is provided in a separate JAR file like log4j-core-2.14.1.jar.

Source Code files for Apache Log4j API are provided in both binary packge like apache-log4j-2.14.1-bin.zip and source package like apache-log4j-2.14.1-src.zip. You can download them at Apache Log4j Website.

You can also browse Source Code files for Apache Log4j Core Implementation 2.14.1 below.

⏎ org/apache/logging/log4j/core/appender/rolling/TimeBasedTriggeringPolicy.java

/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements. See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache license, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License. You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the license for the specific language governing permissions and
 * limitations under the license.
 */
package org.apache.logging.log4j.core.appender.rolling;

import java.util.concurrent.ThreadLocalRandom;
import java.util.concurrent.TimeUnit;

import org.apache.logging.log4j.core.Core;
import org.apache.logging.log4j.core.LogEvent;
import org.apache.logging.log4j.core.config.plugins.Plugin;
import org.apache.logging.log4j.core.config.plugins.PluginAttribute;
import org.apache.logging.log4j.core.config.plugins.PluginBuilderAttribute;
import org.apache.logging.log4j.core.config.plugins.PluginBuilderFactory;
import org.apache.logging.log4j.core.util.Integers;

/**
 * Rolls a file over based on time.
 */
@Plugin(name = "TimeBasedTriggeringPolicy", category = Core.CATEGORY_NAME, printObject = true)
public final class TimeBasedTriggeringPolicy extends AbstractTriggeringPolicy {


    public static class Builder implements org.apache.logging.log4j.core.util.Builder<TimeBasedTriggeringPolicy> {

        @PluginBuilderAttribute
        private int interval = 1;

        @PluginBuilderAttribute
        private boolean modulate = false;

        @PluginBuilderAttribute
        private int maxRandomDelay = 0;

        @Override
        public TimeBasedTriggeringPolicy build() {
            final long maxRandomDelayMillis = TimeUnit.SECONDS.toMillis(maxRandomDelay);
            return new TimeBasedTriggeringPolicy(interval, modulate, maxRandomDelayMillis);
        }

        public int getInterval() {
            return interval;
        }

        public boolean isModulate() {
            return modulate;
        }

        public int getMaxRandomDelay() {
            return maxRandomDelay;
        }

        public Builder withInterval(final int interval){
            this.interval = interval;
            return this;
        }

        public Builder withModulate(final boolean modulate){
            this.modulate = modulate;
            return this;
        }

        public Builder withMaxRandomDelay(final int maxRandomDelay){
            this.maxRandomDelay = maxRandomDelay;
            return this;
        }

    }

    private long nextRolloverMillis;
    private final int interval;
    private final boolean modulate;
    private final long maxRandomDelayMillis;

    private RollingFileManager manager;

    private TimeBasedTriggeringPolicy(final int interval, final boolean modulate, final long maxRandomDelayMillis) {
        this.interval = interval;
        this.modulate = modulate;
        this.maxRandomDelayMillis = maxRandomDelayMillis;
    }

    public int getInterval() {
        return interval;
    }

    public long getNextRolloverMillis() {
        return nextRolloverMillis;
    }

    /**
     * Initializes the policy.
     * @param aManager The RollingFileManager.
     */
    @Override
    public void initialize(final RollingFileManager aManager) {
        this.manager = aManager;
        long current = aManager.getFileTime();
        if (current == 0) {
            current = System.currentTimeMillis();
        }

        // LOG4J2-531: call getNextTime twice to force initialization of both prevFileTime and nextFileTime
        aManager.getPatternProcessor().getNextTime(current, interval, modulate);
        aManager.getPatternProcessor().setTimeBased(true);

        nextRolloverMillis = ThreadLocalRandom.current().nextLong(0, 1 + maxRandomDelayMillis)
                + aManager.getPatternProcessor().getNextTime(current, interval, modulate);
    }

    /**
     * Determines whether a rollover should occur.
     * @param event   A reference to the currently event.
     * @return true if a rollover should occur.
     */
    @Override
    public boolean isTriggeringEvent(final LogEvent event) {
        final long nowMillis = event.getTimeMillis();
        if (nowMillis >= nextRolloverMillis) {
            nextRolloverMillis = ThreadLocalRandom.current().nextLong(0, 1 + maxRandomDelayMillis)
                    + manager.getPatternProcessor().getNextTime(nowMillis, interval, modulate);
            manager.getPatternProcessor().setCurrentFileTime(System.currentTimeMillis());
            return true;
        }
        return false;
    }

    /**
     * Creates a TimeBasedTriggeringPolicy.
     * @param interval The interval between rollovers.
     * @param modulate If true the time will be rounded to occur on a boundary aligned with the increment.
     * @return a TimeBasedTriggeringPolicy.
     * @deprecated Use {@link #newBuilder()}.
     */
    @Deprecated
    public static TimeBasedTriggeringPolicy createPolicy(
            @PluginAttribute("interval") final String interval,
            @PluginAttribute("modulate") final String modulate) {
        return newBuilder()
                .withInterval(Integers.parseInt(interval, 1))
                .withModulate(Boolean.parseBoolean(modulate))
                .build();
    }

    @PluginBuilderFactory
    public static TimeBasedTriggeringPolicy.Builder newBuilder() {
        return new Builder();
    }

    @Override
    public String toString() {
        return "TimeBasedTriggeringPolicy(nextRolloverMillis=" + nextRolloverMillis + ", interval=" + interval
                + ", modulate=" + modulate + ")";
    }

}

⏎ org/apache/logging/log4j/core/appender/rolling/TimeBasedTriggeringPolicy.java

Or download all of them as a single archive file:

File name: log4j-core-2.14.1-sources.jar
File size: 1281358 bytes
Release date: 2021-03-06
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