[CSV-239] Cannot get headers in column order from CSVRecord.

CSVParser.createHeaderNames(Map<String, Integer>) -> private and
instance side.

Author: Gary Gregory

src/main/java/org/apache/commons/csv/CSVParser.java

@@ -183,16 +183,6 @@ public void remove() {
         }
     }
 
-    static List<String> createHeaderNames(final Map<String, Integer> headerMap) {
-        // @formatter:off
-        return headerMap == null ? null
-            : headerMap.entrySet().stream()
-                .sorted(Map.Entry.comparingByValue())
-                .map(Map.Entry::getKey)
-                .collect(Collectors.collectingAndThen(Collectors.toList(), Collections::unmodifiableList));
-        // @formatter:on
-    }
-
     /**
      * Creates a parser for the given {@link File}.
      *
@@ -289,8 +279,6 @@ public static CSVParser parse(final Reader reader, final CSVFormat format) throw
         return new CSVParser(reader, format);
     }
 
-    // the following objects are shared to reduce garbage
-
     /**
      * Creates a parser for the given {@link String}.
      *
@@ -311,6 +299,8 @@ public static CSVParser parse(final String string, final CSVFormat format) throw
         return new CSVParser(new StringReader(string), format);
     }
 
+    // the following objects are shared to reduce garbage
+
     /**
      * Creates a parser for the given URL.
      *
@@ -498,6 +488,16 @@ private Map<String, Integer> createHeaderMap() throws IOException {
         return hdrMap;
     }
 
+    private List<String> createHeaderNames(final Map<String, Integer> headerMap) {
+        // @formatter:off
+        return headerMap == null ? null
+            : headerMap.entrySet().stream()
+                .sorted(Map.Entry.comparingByValue())
+                .map(Map.Entry::getKey)
+                .collect(Collectors.collectingAndThen(Collectors.toList(), Collections::unmodifiableList));
+        // @formatter:on
+    }
+
     /**
      * Returns the current line number in the input stream.
      *