Backport #128 fix

Author: cowtowncoder

release-notes/CREDITS

@@ -56,7 +56,6 @@ Oliver Röss (cloudyday@github)
 * Reported #98: Escape char is not being escaped during serialization
  (2.6.4)
 
-<<<<<<< HEAD
 Justo Ruiz Ferrer (jrferrer@github)
 
 * Contributed #89: Allow choice of using header-line declaration to reorder columns
@@ -84,3 +83,8 @@ Brian Moriarty (morbrian@github)
 
 * Contributed #106: Null fields are always ignored when serializing list of objects
  (2.7.0)
+
+Peter Ansell (ansell@github)
+
+* Contributed fix for #128: Write out headers even if no data rows written
+ (2.7.7)

release-notes/VERSION

@@ -8,6 +8,11 @@ Project: jackson-dataformat-csv
 
 No changes since 2.7.
 
+2.7.7 (not yet released)
+
+#128: Write out headers even if no data rows written
+ (contributed by Peter A)
+
 2.7.6 (23-Jul-2016)
 2.7.5 (11-Jun-2016)
 

src/main/java/com/fasterxml/jackson/dataformat/csv/CsvGenerator.java

@@ -425,6 +425,11 @@ public void close() throws IOException
 
         // Let's mark row as closed, if we had any...
         finishRow();
+         // Write the header if necessary, occurs when no rows written
+         if (_handleFirstLine) {
+             _handleFirstLine();
+         }
+ 
         _writer.close(_ioContext.isResourceManaged() || isEnabled(JsonGenerator.Feature.AUTO_CLOSE_TARGET));
     }