Apache Log4j API provides the interface that applications should code to and provides the adapter components required for implementers to create a logging implementation. Apache Log4j API is a required module to use Apache Log4j.

Bytecode (Java 8) for Apache Log4j API is provided in a separate JAR file like log4j-api-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 API 2.14.1 below.

⏎ org/apache/logging/log4j/util/IndexedReadOnlyStringMap.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.util;

/**
 * An extension of {@code ReadOnlyStringMap} that imposes a total ordering on its keys.
 * The map is ordered according to the natural ordering of its keys. This order is reflected when
 * {@link #forEach(BiConsumer) consuming} the key-value pairs with a {@link BiConsumer} or a {@link TriConsumer}.
 * <p>
 * This interface views all key-value pairs as a sequence ordered by key, and allows
 * keys and values to be accessed by their index in the sequence.
 * </p>
 *
 * @see ReadOnlyStringMap
 * @since 2.8
 */
public interface IndexedReadOnlyStringMap extends ReadOnlyStringMap {

    /**
     * Viewing all key-value pairs as a sequence sorted by key, this method returns the key at the specified index,
     * or {@code null} if the specified index is less than zero or greater or equal to the size of this collection.
     *
     * @param index the index of the key to return
     * @return the key at the specified index or {@code null}
     */
    String getKeyAt(final int index);

    /**
     * Viewing all key-value pairs as a sequence sorted by key, this method returns the value at the specified index,
     * or {@code null} if the specified index is less than zero or greater or equal to the size of this collection.
     *
     * @param index the index of the value to return
     * @return the value at the specified index or {@code null}
     */
    <V> V getValueAt(final int index);

    /**
     * Viewing all key-value pairs as a sequence sorted by key, this method returns the index of the specified key in
     * that sequence. If the specified key is not found, this method returns {@code (-(insertion point) - 1)}.
     *
     * @param key the key whose index in the ordered sequence of keys to return
     * @return the index of the specified key or {@code (-(insertion point) - 1)} if the key is not found.
     *          The insertion point is defined as the point at which the key would be inserted into the array:
     *          the index of the first element in the range greater than the key, or {@code size()} if all elements
     *          are less than the specified key. Note that this guarantees that the return value will be &gt;= 0
     *          if and only if the key is found.
     */
    int indexOfKey(final String key);
}

⏎ org/apache/logging/log4j/util/IndexedReadOnlyStringMap.java

Or download all of them as a single archive file:

File name: log4j-api-2.14.1-sources.jar
File size: 264773 bytes
Release date: 2021-03-06
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