GH-97 Add basic support for passing annotations to the generated Java stubs

plugin/src/main/scala/com/typesafe/genjavadoc/AST.scala

@@ -28,9 +28,19 @@ trait AST { this: TransformCake =>
     static: Boolean,
     var firstConstructor: Boolean) extends Templ {
 
-    def sig = pattern(name, access)
+    def sig: String = {
+      s"""
+         |${addAnnotations}
+         |${pattern(name, access)}""".stripMargin
+    }
+
     def file = filepattern(name)
 
+    private def addAnnotations: String = sym.annotations
+      .filter(a => allowedAnnotations.contains(a.symbol.fullName('.')))
+      .map { a => s"@${a.symbol.fullName('.')}" }
+      .mkString(System.lineSeparator())
+
     def addMember(t: Templ) = copy(members = members :+ t)
 
     def constructor: Boolean = {
@@ -49,7 +59,7 @@ trait AST { this: TransformCake =>
   object ClassInfo {
     def apply(c: ImplDef, comment: Seq[String], topLevel: Boolean): ClassInfo = {
       c match {
-        case ClassDef(mods, _, tparams, impl) =>
+        case cd@ClassDef(mods, _, tparams, impl) =>
           val name = c.name.toString
           val acc = access(mods, topLevel)
           val fl = flags(mods)
@@ -93,9 +103,22 @@ trait AST { this: TransformCake =>
     }
   }
 
-  case class MethodInfo(access: String, pattern: String => String, ret: String, name: String, comment: Seq[String]) extends Templ {
-    def sig = pattern(s"$ret $name")
+  case class MethodInfo(access: String, pattern: String => String, ret: String, name: String, comment: Seq[String], d: Option[DefDef] = None) extends Templ {
+    def sig: String = {
+      s"""
+         |${addAnnotations}
+         |${pattern(s"$ret $name")}""".stripMargin
+    }
+
+    private def addAnnotations: String = d match {
+      case Some(definition) => definition.symbol.annotations
+        .filter(a => allowedAnnotations.contains(a.symbol.fullName('.')))
+        .map { a => s"@${a.symbol.fullName('.')}" }
+        .mkString(System.lineSeparator())
+      case None => ""
+    }
   }
+
   object MethodInfo {
     def apply(d: DefDef, interface: Boolean, comment: Seq[String], hasVararg: Boolean, deprecation: Option[DeprecationInfo]): MethodInfo = {
       val acc = methodAccess(d.symbol, interface) + methodFlags(d.mods, interface)
@@ -139,7 +162,7 @@ trait AST { this: TransformCake =>
           case Some(deprec) => deprec.appendToComment(commentWithParams)
           case _ => commentWithParams
         }
-      MethodInfo(acc, pattern, ret, name, commentWithParamsAndDeprec)
+      MethodInfo(acc, pattern, ret, name, commentWithParamsAndDeprec, Some(d))
     }
 
     /**

plugin/src/main/scala/com/typesafe/genjavadoc/Plugin.scala

@@ -8,6 +8,7 @@ import nsc.transform.Transform
 import java.io.File
 import java.util.Properties
 
+
 object GenJavadocPlugin {
 
   val javaKeywords = Set("abstract", "assert", "boolean", "break", "byte", "case", "catch", "char", "class", "const", "continue",
@@ -48,11 +49,10 @@ class GenJavadocPlugin(val global: Global) extends Plugin {
   lazy val filteredStrings: Set[String] = stringToFilter(myOptions.getProperty("filter", defaultFilterString))
   lazy val fabricateParams = java.lang.Boolean.parseBoolean(myOptions.getProperty("fabricateParams", "true"))
   lazy val strictVisibility = java.lang.Boolean.parseBoolean(myOptions.getProperty("strictVisibility", "false"))
+  lazy val allowedAnnotations: Set[String] = stringToFilter(myOptions.getProperty("annotations", ""))
 
   private object MyComponent extends PluginComponent with Transform {
 
-    import global._
-
     type GT = GenJavadocPlugin.this.global.type
 
     override val global: GT = GenJavadocPlugin.this.global
@@ -78,6 +78,8 @@ class GenJavadocPlugin(val global: Global) extends Plugin {
       override def transformUnit(unit: CompilationUnit) = newTransformUnit(unit)
       override def javaKeywords = GenJavadocPlugin.javaKeywords
       override def filteredStrings = GenJavadocPlugin.this.filteredStrings
+
+      override def allowedAnnotations: Set[String] = GenJavadocPlugin.this.allowedAnnotations
     }
   }
 }

plugin/src/main/scala/com/typesafe/genjavadoc/TransformCake.scala

@@ -14,4 +14,6 @@ trait TransformCake extends JavaSig with Output with Comments with BasicTransfor
   def javaKeywords: Set[String]
 
   def filteredStrings: Set[String]
+
+  def allowedAnnotations: Set[String]
 }