Replace the incompatible new interface method endSheet() with a Java 8 default method so existing implementations do not need to be adjusted. Also use this for headerFooter() and remove the empty implementations that are now obsolete.

git-svn-id: https://svn.apache.org/repos/asf/poi/trunk@1809635 13f79535-47bb-0310-9956-ffa450edef68

src/examples/src/org/apache/poi/xssf/eventusermodel/XLSX2CSV.java

@@ -135,15 +135,6 @@ public class XLSX2CSV {
                 output.append('"');
             }
         }
-
-        @Override
-        public void headerFooter(String text, boolean isHeader, String tagName) {
-            // Skip, no headers or footers in CSV
-        }
-
-        @Override
-        public void endSheet() {
-        }
     }
 
 

src/examples/src/org/apache/poi/xssf/streaming/examples/HybridStreaming.java

@@ -64,10 +64,6 @@ public class HybridStreaming {
             public void startRow(int rowNum) {
             }
             
-            @Override
-            public void headerFooter(String text, boolean isHeader, String tagName) {
-            }
-            
             @Override
             public void endRow(int rowNum) {
             }
@@ -75,12 +71,6 @@ public class HybridStreaming {
             @Override
             public void cell(String cellReference, String formattedValue, XSSFComment comment) {
             }
-
-            @Override
-            public void endSheet() {
-
-            }
         };
     }
-
 }

src/ooxml/java/org/apache/poi/xssf/eventusermodel/XSSFSheetXMLHandler.java

@@ -515,9 +515,9 @@ public class XSSFSheetXMLHandler extends DefaultHandler {
       public void cell(String cellReference, String formattedValue, XSSFComment comment);
 
       /** A header or footer has been encountered */
-      public void headerFooter(String text, boolean isHeader, String tagName);
+      public default void headerFooter(String text, boolean isHeader, String tagName) {}
 
       /** Signal that the end of a sheet was been reached */
-      public void endSheet();
+      public default void endSheet() {}
    }
 }

src/ooxml/java/org/apache/poi/xssf/extractor/XSSFEventBasedExcelExtractor.java

@@ -342,10 +342,6 @@ public class XSSFEventBasedExcelExtractor extends POIXMLTextExtractor
             output.append('\n');
         }
 
-        @Override
-        public void endSheet() {
-        }
-
         @Override
         public void cell(String cellRef, String formattedValue, XSSFComment comment) {
             if(firstCellOfRow) {