1 files changed, 12 insertions, 9 deletions
diff --git a/src/main/java/com/squareup/javapoet/ParameterSpec.java b/src/main/java/com/squareup/javapoet/ParameterSpec.java
index b8f3129..8b2b6ed 100644
--- a/src/main/java/com/squareup/javapoet/ParameterSpec.java
+++ b/src/main/java/com/squareup/javapoet/ParameterSpec.java
@@ -21,7 +21,6 @@ import java.util.ArrayList;
 import java.util.Collections;
 import java.util.List;
 import java.util.Set;
-import java.util.stream.Collectors;
 import javax.lang.model.SourceVersion;
 import javax.lang.model.element.ElementKind;
 import javax.lang.model.element.ExecutableElement;
@@ -87,17 +86,12 @@ public final class ParameterSpec {
   public static ParameterSpec get(VariableElement element) {
     checkArgument(element.getKind().equals(ElementKind.PARAMETER), "element is not a parameter");
 
-    // Copy over any annotations from element.
-    List<AnnotationSpec> annotations = element.getAnnotationMirrors()
-        .stream()
-        .map((mirror) -> AnnotationSpec.get(mirror))
-        .collect(Collectors.toList());
-
     TypeName type = TypeName.get(element.asType());
     String name = element.getSimpleName().toString();
+    // Copying parameter annotations can be incorrect so we're deliberately not including them.
+    // See https://github.com/square/javapoet/issues/482.
     return ParameterSpec.builder(type, name)
         .addModifiers(element.getModifiers())
-        .addAnnotations(annotations)
         .build();
   }
 
@@ -109,9 +103,18 @@ public final class ParameterSpec {
     return result;
   }
 
+  private static boolean isValidParameterName(String name) {
+    // Allow "this" for explicit receiver parameters
+    // See https://docs.oracle.com/javase/specs/jls/se8/html/jls-8.html#jls-8.4.1.
+    if (name.endsWith(".this")) {
+      return SourceVersion.isIdentifier(name.substring(0, name.length() - ".this".length()));
+    }
+    return name.equals("this") || SourceVersion.isName(name);
+  }
+
   public static Builder builder(TypeName type, String name, Modifier... modifiers) {
     checkNotNull(type, "type == null");
-    checkArgument(SourceVersion.isName(name), "not a valid name: %s", name);
+    checkArgument(isValidParameterName(name), "not a valid name: %s", name);
     return new Builder(type, name)
         .addModifiers(modifiers);
   }