Add an option in EndSpanOptions to register the span name for sampled store. (#703)

* Add an option in SpanBuilder to register the span name for sampled store.

* Change to LocalSpanStore name the SpanBuilder.

* Move the option to EndSpanOptions.

* Fix comments.

1 files changed, 52 insertions, 0 deletions

diff --git a/api/src/main/java/io/opencensus/common/ExperimentalApi.java b/api/src/main/java/io/opencensus/common/ExperimentalApi.java
new file mode 100644
index 00000000..266da4e9
--- /dev/null
+++ b/api/src/main/java/io/opencensus/common/ExperimentalApi.java
@@ -0,0 +1,52 @@
+/*
+ * Copyright 2017, OpenCensus Authors
+ *
+ * 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 io.opencensus.common;
+
+import java.lang.annotation.Documented;
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+/**
+ * Indicates a public API that can change at any time, and has no guarantee of API stability and
+ * backward-compatibility.
+ *
+ * <p>Usage guidelines:
+ * <ol>
+ * <li>This annotation is used only on public API. Internal interfaces should not use it.</li>
+ * <li>After OpenCensus has gained API stability, this annotation can only be added to new API.
+ * Adding it to an existing API is considered API-breaking.</li>
+ * <li>Removing this annotation from an API gives it stable status.</li>
+ * </ol>
+ */
+@Internal
+@Retention(RetentionPolicy.SOURCE)
+@Target({
+    ElementType.ANNOTATION_TYPE,
+    ElementType.CONSTRUCTOR,
+    ElementType.FIELD,
+    ElementType.METHOD,
+    ElementType.PACKAGE,
+    ElementType.TYPE})
+@Documented
+public @interface ExperimentalApi {
+  /**
+   * Context information such as links to discussion thread, tracking issue etc.
+   */
+  String value() default "";
+}
\ No newline at end of file