Add an implementation of generatedAnnotation that uses the source ver…

…sion instead of classpath introspection. RELNOTES=N/A ------------- Created by MOE: https://github.com/google/moe MOE_MIGRATED_REVID=181173931
google · Jan 8, 2018 · 0383c1c · 0383c1c
1 parent d5ca4ab
commit 0383c1c
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diff --git a/common/src/main/java/com/google/auto/common/GeneratedAnnotationSpecs.java b/common/src/main/java/com/google/auto/common/GeneratedAnnotationSpecs.java
@@ -18,6 +18,7 @@
 import com.squareup.javapoet.AnnotationSpec;
 import com.squareup.javapoet.ClassName;
 import java.util.Optional;
+import javax.lang.model.SourceVersion;
 import javax.lang.model.util.Elements;
 
 /** Utility methods for writing {@code @Generated} annotations using JavaPoet. */
@@ -29,7 +30,10 @@ private GeneratedAnnotationSpecs() {}
    * Returns {@code @Generated("processorClass"} if either {@code
    * javax.annotation.processing.Generated} or {@code javax.annotation.Generated} is {@linkplain
    * GeneratedAnnotations#generatedAnnotation(Elements) available at compile time}.
+   *
+   * @deprecated prefer {@link #generatedAnnotationSpec(Elements, SourceVersion, Class<?>)}
    */
+  @Deprecated
   public static Optional<AnnotationSpec> generatedAnnotationSpec(
       Elements elements, Class<?> processorClass) {
     return generatedAnnotationSpecBuilder(elements, processorClass)
@@ -40,7 +44,10 @@ public static Optional<AnnotationSpec> generatedAnnotationSpec(
    * Returns {@code @Generated(value = "processorClass", comments = "comments"} if either {@code
    * javax.annotation.processing.Generated} or {@code javax.annotation.Generated} is {@linkplain
    * GeneratedAnnotations#generatedAnnotation(Elements) available at compile time}.
+   *
+   * @deprecated prefer {@link #generatedAnnotationSpec(Elements, SourceVersion, Class<?>, String)}
    */
+  @Deprecated
   public static Optional<AnnotationSpec> generatedAnnotationSpec(
       Elements elements, Class<?> processorClass, String comments) {
     return generatedAnnotationSpecBuilder(elements, processorClass)
@@ -55,4 +62,40 @@ private static Optional<AnnotationSpec.Builder> generatedAnnotationSpecBuilder(
                 AnnotationSpec.builder(ClassName.get(generated))
                     .addMember("value", "$S", processorClass.getCanonicalName()));
   }
+
+  /**
+   * Returns {@code @Generated("processorClass"} for the target {@code SourceVersion}.
+   *
+   * <p>Returns {@code javax.annotation.processing.Generated} for JDK 9 and newer, {@code
+   * javax.annotation.Generated} for earlier releases, and Optional#empty()} if the annotation is
+   * not available.
+   */
+  public static Optional<AnnotationSpec> generatedAnnotationSpec(
+      Elements elements, SourceVersion sourceVersion, Class<?> processorClass) {
+    return generatedAnnotationSpecBuilder(elements, sourceVersion, processorClass)
+        .map(AnnotationSpec.Builder::build);
+  }
+
+  /**
+   * Returns {@code @Generated(value = "processorClass", comments = "comments"} for the target
+   * {@code SourceVersion}.
+   *
+   * <p>Returns {@code javax.annotation.processing.Generated} for JDK 9 and newer, {@code
+   * javax.annotation.Generated} for earlier releases, and Optional#empty()} if the annotation is
+   * not available.
+   */
+  public static Optional<AnnotationSpec> generatedAnnotationSpec(
+      Elements elements, SourceVersion sourceVersion, Class<?> processorClass, String comments) {
+    return generatedAnnotationSpecBuilder(elements, sourceVersion, processorClass)
+        .map(annotation -> annotation.addMember("comments", "$S", comments).build());
+  }
+
+  private static Optional<AnnotationSpec.Builder> generatedAnnotationSpecBuilder(
+      Elements elements, SourceVersion sourceVersion, Class<?> processorClass) {
+    return GeneratedAnnotations.generatedAnnotation(elements, sourceVersion)
+        .map(
+            generated ->
+                AnnotationSpec.builder(ClassName.get(generated))
+                    .addMember("value", "$S", processorClass.getCanonicalName()));
+  }
 }
diff --git a/common/src/main/java/com/google/auto/common/GeneratedAnnotations.java b/common/src/main/java/com/google/auto/common/GeneratedAnnotations.java
@@ -16,6 +16,7 @@
 package com.google.auto.common;
 
 import java.util.Optional;
+import javax.lang.model.SourceVersion;
 import javax.lang.model.element.TypeElement;
 import javax.lang.model.util.Elements;
 
@@ -30,12 +31,32 @@ private GeneratedAnnotations() {}
    * <p>First looks for {@code javax.annotation.processing.Generated}, and then {@code
    * javax.annotation.Generated}. Returns whichever is in the classpath (or modulepath), or {@link
    * Optional#empty()} if neither is.
+   *
+   * @deprecated prefer {@link #generatedAnnotation(Elements, SourceVersion)}
    */
+  @Deprecated
   public static Optional<TypeElement> generatedAnnotation(Elements elements) {
     TypeElement jdk9Generated = elements.getTypeElement("javax.annotation.processing.Generated");
     if (jdk9Generated != null) {
       return Optional.of(jdk9Generated);
     }
     return Optional.ofNullable(elements.getTypeElement("javax.annotation.Generated"));
   }
+
+  /**
+   * Returns the element corresponding to the {@code @Generated} annotation present at the target
+   * {@code SourceVersion}.
+   *
+   * <p>Returns {@code javax.annotation.processing.Generated} for JDK 9 and newer, {@code
+   * javax.annotation.Generated} for earlier releases, and Optional#empty()} if the annotation is
+   * not available.
+   */
+  public static Optional<TypeElement> generatedAnnotation(
+      Elements elements, SourceVersion sourceVersion) {
+    return Optional.ofNullable(
+        elements.getTypeElement(
+            sourceVersion.compareTo(SourceVersion.RELEASE_8) > 0
+                ? "javax.annotation.processing.Generated"
+                : "javax.annotation.Generated"));
+  }
 }