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Diffstat (limited to 'kamon-annotation/src/main/java/kamon/annotation/Segment.java')
-rw-r--r-- | kamon-annotation/src/main/java/kamon/annotation/Segment.java | 78 |
1 files changed, 78 insertions, 0 deletions
diff --git a/kamon-annotation/src/main/java/kamon/annotation/Segment.java b/kamon-annotation/src/main/java/kamon/annotation/Segment.java new file mode 100644 index 00000000..8d69e84a --- /dev/null +++ b/kamon-annotation/src/main/java/kamon/annotation/Segment.java @@ -0,0 +1,78 @@ +/* + * ========================================================================================= + * Copyright © 2013-2015 the kamon project <http://kamon.io/> + * + * Licensed 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 kamon.annotation; + +import java.lang.annotation.*; + +/** + * A marker annotation to start a new Segment. + * <p> + * <p> + * Given a method like this: + * <pre><code> + * {@literal @}Segment("coolSegmentName", tags="${'my-cool-tag':'my-cool-value'}") + * public String coolName(String name) { + * return "Hello " + name; + * } + * </code></pre> + * <p> + * <p> + * A new Segment will be created only if in the moment of the method execution exist a TraceContext. + */ +@Documented +@Target(ElementType.METHOD) +@Retention(RetentionPolicy.RUNTIME) +public @interface Segment { + + /** + * @return The Segment's name. + * <p> + * Also, the Segment name can be resolved with an EL expression that evaluates to a String: + * <p> + * <pre> + * {@code + * class Segment { + * private long id; + * + * public long getId() { return id; } + * + * {@literal @}Segment (name = "${'segmentID:' += this.id}") + * void segment() {} // create a Segment with name => segmentID:[id] + * } + * } + * </pre> + */ + String name(); + + /** + * @return The Segment's category. + */ + String category(); + + /** + * @return The Segment's library. + */ + String library(); + + /** + * Tags are a way of adding dimensions to metrics, + * these are constructed using EL syntax e.g. "${'algorithm':'1','env':'production'}" + * + * @return the tags associated to the segment + */ + String tags() default ""; +} |