3 files changed, 29 insertions, 2 deletions
diff --git a/src/java/org/apache/poi/ss/formula/ptg/Area3DPxg.java b/src/java/org/apache/poi/ss/formula/ptg/Area3DPxg.java
index e27ccdd7a1..665ac98cfb 100644
--- a/src/java/org/apache/poi/ss/formula/ptg/Area3DPxg.java
+++ b/src/java/org/apache/poi/ss/formula/ptg/Area3DPxg.java
@@ -31,7 +31,7 @@ import org.apache.poi.util.LittleEndianOutput;
  * <p>This is XSSF only, as it stores the sheet / book references
  *  in String form. The HSSF equivalent using indexes is {@link Area3DPtg}</p>
  */
-public final class Area3DPxg extends AreaPtgBase implements Pxg {
+public final class Area3DPxg extends AreaPtgBase implements Pxg3D {
     private int externalWorkbookNumber = -1;
     private String firstSheetName;
     private String lastSheetName;
diff --git a/src/java/org/apache/poi/ss/formula/ptg/Pxg3D.java b/src/java/org/apache/poi/ss/formula/ptg/Pxg3D.java
new file mode 100644
index 0000000000..49083fe150
--- /dev/null
+++ b/src/java/org/apache/poi/ss/formula/ptg/Pxg3D.java
@@ -0,0 +1,27 @@
+/* ====================================================================
+   Licensed to the Apache Software Foundation (ASF) under one or more
+   contributor license agreements.  See the NOTICE file distributed with
+   this work for additional information regarding copyright ownership.
+   The ASF licenses this file to You under the Apache License, Version 2.0
+   (the "License"); you may not use this file except in compliance with
+   the License.  You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
+==================================================================== */
+
+package org.apache.poi.ss.formula.ptg;
+
+/**
+ * An XSSF only special kind of Ptg, which stores a range of 
+ *  sheet / book references in string form.
+ */
+public interface Pxg3D extends Pxg {
+    public String getLastSheetName();
+    public void setLastSheetName(String sheetName);
+}
diff --git a/src/java/org/apache/poi/ss/formula/ptg/Ref3DPxg.java b/src/java/org/apache/poi/ss/formula/ptg/Ref3DPxg.java
index 41039cd927..3b78c5a4b0 100644
--- a/src/java/org/apache/poi/ss/formula/ptg/Ref3DPxg.java
+++ b/src/java/org/apache/poi/ss/formula/ptg/Ref3DPxg.java
@@ -31,7 +31,7 @@ import org.apache.poi.util.LittleEndianOutput;
  * <p>This is XSSF only, as it stores the sheet / book references
  *  in String form. The HSSF equivalent using indexes is {@link Ref3DPtg}</p>
  */
-public final class Ref3DPxg extends RefPtgBase implements Pxg {
+public final class Ref3DPxg extends RefPtgBase implements Pxg3D {
     private int externalWorkbookNumber = -1;
     private String firstSheetName;
     private String lastSheetName;