8295823: Use enhanced-for cycle instead of Enumeration in java.naming

Reviewed-by: aefimov, dfuchs, vtewari

Author: Andrey Turbanov

src/java.naming/share/classes/javax/naming/directory/BasicAttribute.java

@@ -215,10 +215,10 @@ public String toString() {
             answer.append("No values");
         } else {
             boolean start = true;
-            for (Enumeration<Object> e = values.elements(); e.hasMoreElements(); ) {
+            for (Object value : values) {
                 if (!start)
                     answer.append(", ");
-                answer.append(e.nextElement());
+                answer.append(value);
                 start = false;
             }
         }

src/java.naming/share/classes/javax/naming/directory/BasicAttributes.java

@@ -294,9 +294,8 @@ private void writeObject(java.io.ObjectOutputStream s)
         // Overridden to avoid exposing implementation details
         s.defaultWriteObject(); // write out the ignoreCase flag
         s.writeInt(attrs.size());
-        Enumeration<Attribute> attrEnum = attrs.elements();
-        while (attrEnum.hasMoreElements()) {
-            s.writeObject(attrEnum.nextElement());
+        for (Attribute attribute : attrs.values()) {
+            s.writeObject(attribute);
         }
     }