Apply some static code analysis recommendations

Fix a batch of code inspection recommendations generated by IntelliJ 14.1.5.

Categories of fix,

  Unnecessary public modifier in interface
  Replace filter+size with count
  Replace filter+nonEmpty with exists
  Replace filter+headOption with find
  Replace `if (x != null) Some(x) else None` with Option(x)
  Replace getOrElse null with orNull
  Drop redundant semicolons
  Replace anon fun with PF
  Replace anon fun with method

Author: janekdb

src/library/scala/reflect/ScalaLongSignature.java

@@ -8,5 +8,5 @@
 @Retention(RetentionPolicy.RUNTIME)
 @Target(ElementType.TYPE)
 public @interface ScalaLongSignature {
-    public String[] bytes();
+    String[] bytes();
 }

src/library/scala/reflect/ScalaSignature.java

@@ -8,5 +8,5 @@
 @Retention(RetentionPolicy.RUNTIME)
 @Target(ElementType.TYPE)
 public @interface ScalaSignature {
-    public String bytes();
+    String bytes();
 }

src/reflect/scala/reflect/internal/util/WeakHashSet.scala

@@ -41,7 +41,7 @@ final class WeakHashSet[A <: AnyRef](val initialCapacity: Int, val loadFactor: D
    * power of two equal to or greater than the specified initial capacity
    */
   private def computeCapacity = {
-    if (initialCapacity < 0) throw new IllegalArgumentException("initial capacity cannot be less than 0");
+    if (initialCapacity < 0) throw new IllegalArgumentException("initial capacity cannot be less than 0")
     var candidate = 1
     while (candidate < initialCapacity) {
       candidate  *= 2
@@ -372,13 +372,13 @@ final class WeakHashSet[A <: AnyRef](val initialCapacity: Int, val loadFactor: D
      * Number of buckets that hold collisions. Useful for diagnosing performance issues.
      */
     def collisionBucketsCount: Int =
-      (table filter (entry => entry != null && entry.tail != null)).size
+      (table count (entry => entry != null && entry.tail != null))
 
     /**
      * Number of buckets that are occupied in this hash table.
      */
     def fullBucketsCount: Int =
-      (table filter (entry => entry != null)).size
+      (table count (entry => entry != null))
 
     /**
      *  Number of buckets in the table

src/reflect/scala/reflect/macros/Attachments.scala

@@ -39,7 +39,7 @@ abstract class Attachments { self =>
 
   /** An underlying payload of the given class type `T`. */
   def get[T: ClassTag]: Option[T] =
-    (all filter matchesTag[T]).headOption.asInstanceOf[Option[T]]
+    (all find matchesTag[T]).asInstanceOf[Option[T]]
 
   /** Check underlying payload contains an instance of type `T`. */
   def contains[T: ClassTag]: Boolean =

src/reflect/scala/reflect/runtime/ReflectionUtils.scala

@@ -72,7 +72,7 @@ object ReflectionUtils {
     def singletonAccessor(clazz: Class[_]): Option[Method] =
       if (clazz == null) None
       else {
-        val declaredAccessor = clazz.getDeclaredMethods.filter(_.getName == accessorName).headOption
+        val declaredAccessor = clazz.getDeclaredMethods.find(_.getName == accessorName)
         declaredAccessor orElse singletonAccessor(clazz.getSuperclass)
       }
 
@@ -92,7 +92,7 @@ object ReflectionUtils {
   }
 
   class EnclosedIn[T](enclosure: jClass[_] => T) {
-    def unapply(jclazz: jClass[_]): Option[T] = if (enclosure(jclazz) != null) Some(enclosure(jclazz)) else None
+    def unapply(jclazz: jClass[_]): Option[T] = Option(enclosure(jclazz))
   }
 
   object EnclosedInMethod extends EnclosedIn(_.getEnclosingMethod)

src/reflect/scala/reflect/runtime/SynchronizedOps.scala

@@ -15,7 +15,7 @@ private[reflect] trait SynchronizedOps extends internal.SymbolTable
 
   override protected def newBaseTypeSeq(parents: List[Type], elems: Array[Type]) =
     // only need to synchronize BaseTypeSeqs if they contain refined types
-    if (elems.filter(_.isInstanceOf[RefinedType]).nonEmpty) new BaseTypeSeq(parents, elems) with SynchronizedBaseTypeSeq
+    if (elems.exists(_.isInstanceOf[RefinedType])) new BaseTypeSeq(parents, elems) with SynchronizedBaseTypeSeq
     else new BaseTypeSeq(parents, elems)
 
   trait SynchronizedBaseTypeSeq extends BaseTypeSeq {
@@ -31,7 +31,7 @@ private[reflect] trait SynchronizedOps extends internal.SymbolTable
 
     override def lateMap(f: Type => Type): BaseTypeSeq =
       // only need to synchronize BaseTypeSeqs if they contain refined types
-      if (map(f).toList.filter(_.isInstanceOf[RefinedType]).nonEmpty) new MappedBaseTypeSeq(this, f) with SynchronizedBaseTypeSeq
+      if (map(f).toList.exists(_.isInstanceOf[RefinedType])) new MappedBaseTypeSeq(this, f) with SynchronizedBaseTypeSeq
       else new MappedBaseTypeSeq(this, f)
   }
 

src/repl/scala/tools/nsc/interpreter/JLineCompletion.scala

@@ -175,7 +175,7 @@ class JLineCompletion(val intp: IMain) extends Completion with CompletionOutput
         case Some((clazz, runtimeType)) =>
           val sym = intp.symbolOfTerm(id)
           if (sym.isStable) {
-            val param = new NamedParam.Untyped(id, intp valueOfTerm id getOrElse null)
+            val param = new NamedParam.Untyped(id, intp valueOfTerm id orNull)
             Some(TypeMemberCompletion(tpe, runtimeType, param))
           }
           else default

src/repl/scala/tools/nsc/interpreter/JavapClass.scala

@@ -600,11 +600,11 @@ object JavapClass {
     def parents: List[ClassLoader] = parentsOf(loader)
     /* all file locations */
     def locations = {
-      def alldirs = parents flatMap (_ match {
+      def alldirs = parents flatMap {
         case ucl: ScalaClassLoader.URLClassLoader => ucl.classPathURLs
         case jcl: java.net.URLClassLoader         => jcl.getURLs
         case _ => Nil
-      })
+      }
       val dirs = for (d <- alldirs; if d.getProtocol == "file") yield Path(new JFile(d.toURI))
       dirs
     }

src/scalap/scala/tools/scalap/CodeWriter.scala

@@ -35,7 +35,7 @@ class CodeWriter(writer: Writer) {
   def setIndentWidth(width: Int): CodeWriter =
     setIndentString(List.fill(width)(' ').mkString)
 
-  def getIndentString = step;
+  def getIndentString = step
 
   def setIndentString(step: String): CodeWriter = {
     this.step = step

src/scalap/scala/tools/scalap/Decode.scala

@@ -49,7 +49,7 @@ object Decode {
     import classFile._
 
     classFile annotation SCALA_SIG_ANNOTATION map { case Annotation(_, els) =>
-      val bytesElem = els find (x => constant(x.elementNameIndex) == BYTES_VALUE) getOrElse null
+      val bytesElem = els find (x => constant(x.elementNameIndex) == BYTES_VALUE) orNull
       val _bytes    = bytesElem.elementValue match { case ConstValueIndex(x) => constantWrapped(x) }
       val bytes     = _bytes.asInstanceOf[StringBytesPair].bytes
       val length    = ByteCodecs.decode(bytes)