1 /* 2 * Copyright (c) 2016, 2018, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. Oracle designates this 8 * particular file as subject to the "Classpath" exception as provided 9 * by Oracle in the LICENSE file that accompanied this code. 10 * 11 * This code is distributed in the hope that it will be useful, but WITHOUT 12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 14 * version 2 for more details (a copy is included in the LICENSE file that 15 * accompanied this code). 16 * 17 * You should have received a copy of the GNU General Public License version 18 * 2 along with this work; if not, write to the Free Software Foundation, 19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 20 * 21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 22 * or visit www.oracle.com if you need additional information or have any 23 * questions. 24 */ 25 26 package jdk.jfr; 27 28 import java.lang.annotation.ElementType; 29 import java.lang.annotation.Retention; 30 import java.lang.annotation.RetentionPolicy; 31 import java.lang.annotation.Target; 32 33 /** 34 * Event field annotation, specifies that the value is a duration. 35 * 36 * @since 9 37 */ 38 @MetadataDefinition 39 @ContentType 40 @Label("Timespan") 41 @Description("A duration, measured in nanoseconds by default") 42 @Retention(RetentionPolicy.RUNTIME) 43 @Target({ ElementType.FIELD, ElementType.TYPE, ElementType.METHOD}) 44 public @interface Timespan { 45 /** 46 * Unit for ticks. 47 */ 48 public static final String TICKS = "TICKS"; 49 /** 50 * Unit for seconds. 51 */ 52 public static final String SECONDS = "SECONDS"; 53 /** 54 * Unit for milliseconds. 55 */ 56 public static final String MILLISECONDS = "MILLISECONDS"; 57 /** 58 * Unit for nanoseconds. 59 */ 60 public static final String NANOSECONDS = "NANOSECONDS"; 61 62 /** 63 * Unit for microseconds. 64 */ 65 public static final String MICROSECONDS = "MICROSECONDS"; 66 67 /** 68 * Returns the unit of measure for the time span. 69 * <p> 70 * By default, the unit is nanoseconds. 71 * 72 * @return the time span unit, default {@code #NANOSECONDS}, not {@code null} 73 */ value()74 String value() default NANOSECONDS; 75 } 76