1 /* 2 * Licensed to the Apache Software Foundation (ASF) under one or more 3 * contributor license agreements. See the NOTICE file distributed with 4 * this work for additional information regarding copyright ownership. 5 * The ASF licenses this file to You under the Apache license, Version 2.0 6 * (the "License"); you may not use this file except in compliance with 7 * the License. You may obtain a copy of the License at 8 * 9 * http://www.apache.org/licenses/LICENSE-2.0 10 * 11 * Unless required by applicable law or agreed to in writing, software 12 * distributed under the License is distributed on an "AS IS" BASIS, 13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 14 * See the license for the specific language governing permissions and 15 * limitations under the license. 16 */ 17 package org.apache.logging.log4j.core.time; 18 19 import org.apache.logging.log4j.core.util.Clock; 20 import org.apache.logging.log4j.util.StringBuilderFormattable; 21 22 /** 23 * Models a point in time, suitable for event timestamps. 24 * <p> 25 * Provides methods for obtaining high precision time information similar to the 26 * <a href="https://docs.oracle.com/javase/9/docs/api/java/time/Instant.html">Instant</a> class introduced in Java 8, 27 * while also supporting the legacy millisecond precision API. 28 * </p><p> 29 * Depending on the platform, time sources ({@link Clock} implementations) may produce high precision or millisecond 30 * precision time values. At the same time, some time value consumers (for example timestamp formatters) may only be 31 * able to consume time values of millisecond precision, while some others may require a high precision time value. 32 * </p><p> 33 * This class bridges these two time APIs. 34 * </p> 35 * @since 2.11 36 */ 37 public interface Instant extends StringBuilderFormattable { 38 /** 39 * Gets the number of seconds from the Java epoch of 1970-01-01T00:00:00Z. 40 * <p> 41 * The epoch second count is a simple incrementing count of seconds where second 0 is 1970-01-01T00:00:00Z. 42 * The nanosecond part of the day is returned by {@link #getNanoOfSecond()}. 43 * </p> 44 * @return the seconds from the epoch of 1970-01-01T00:00:00Z 45 */ 46 long getEpochSecond(); 47 48 /** 49 * Gets the number of nanoseconds, later along the time-line, from the start of the second. 50 * <p> 51 * The nanosecond-of-second value measures the total number of nanoseconds from the second returned by {@link #getEpochSecond()}. 52 * </p> 53 * @return the nanoseconds within the second, always positive, never exceeds {@code 999,999,999} 54 */ 55 int getNanoOfSecond(); 56 57 /** 58 * Gets the number of milliseconds from the Java epoch of 1970-01-01T00:00:00Z. 59 * <p> 60 * The epoch millisecond count is a simple incrementing count of milliseconds where millisecond 0 is 1970-01-01T00:00:00Z. 61 * The nanosecond part of the day is returned by {@link #getNanoOfMillisecond()}. 62 * </p> 63 * @return the milliseconds from the epoch of 1970-01-01T00:00:00Z 64 */ 65 long getEpochMillisecond(); 66 67 /** 68 * Gets the number of nanoseconds, later along the time-line, from the start of the millisecond. 69 * <p> 70 * The nanosecond-of-millisecond value measures the total number of nanoseconds from the millisecond returned by {@link #getEpochMillisecond()}. 71 * </p> 72 * @return the nanoseconds within the millisecond, always positive, never exceeds {@code 999,999} 73 */ 74 int getNanoOfMillisecond(); 75 }