title: java apache poi shifting Rows runs into a runtime exception
body: <p>I have a simple excel sheet with basic excel formulas, such as sums, and value retrieval from another cell. Now, I want to essentially insert a blank line in between two existing lines (I've taken a look at <a href="https://stackoverflow.com/questions/5785724/how-to-insert-a-row-between-two-rows-in-an-existing-excel-with-hssf-apache-poi">How to insert a row between two rows in an existing excel with HSSF (Apache POI)</a>, but I'm running into some strange errors). </p>
  
  <p>So I tried shifting rows by doing this:</p>
  
  <pre><code>worksheet.shiftRows(15,16,2);
  </code></pre>
  
  <p>and I'm getting this in return:</p>
  
  <pre><code>Exception in thread "main" java.lang.RuntimeException: not implemented yet
      at org.apache.poi.xssf.usermodel.XSSFEvaluationWorkbook.getExternalSheetIndex(XSSFEvaluationWorkbook.java:127)
      at org.apache.poi.ss.formula.FormulaParser.createAreaRefParseNode(FormulaParser.java:615)
      at org.apache.poi.ss.formula.FormulaParser.parseRangeable(FormulaParser.java:462)
      at org.apache.poi.ss.formula.FormulaParser.parseRangeExpression(FormulaParser.java:268)
      at org.apache.poi.ss.formula.FormulaParser.parseSimpleFactor(FormulaParser.java:1119)
      at org.apache.poi.ss.formula.FormulaParser.percentFactor(FormulaParser.java:1079)
      at org.apache.poi.ss.formula.FormulaParser.powerFactor(FormulaParser.java:1066)
      at org.apache.poi.ss.formula.FormulaParser.Term(FormulaParser.java:1426)
      at org.apache.poi.ss.formula.FormulaParser.additiveExpression(FormulaParser.java:1526)
      at org.apache.poi.ss.formula.FormulaParser.concatExpression(FormulaParser.java:1510)
      at org.apache.poi.ss.formula.FormulaParser.comparisonExpression(FormulaParser.java:1467)
      at org.apache.poi.ss.formula.FormulaParser.unionExpression(FormulaParser.java:1447)
      at org.apache.poi.ss.formula.FormulaParser.parse(FormulaParser.java:1568)
      at org.apache.poi.ss.formula.FormulaParser.parse(FormulaParser.java:176)
      at org.apache.poi.xssf.usermodel.helpers.XSSFRowShifter.updateNamedRanges(XSSFRowShifter.java:116)
      at org.apache.poi.xssf.usermodel.XSSFSheet.shiftRows(XSSFSheet.java:2363)
      at org.apache.poi.xssf.usermodel.XSSFSheet.shiftRows(XSSFSheet.java:2306)
      at com.shel.myProgram.workbook.copyAndInsert(workbook.java:120)
      at com.shel.myProgram.workbook.test(workbook.java:111)
      at com.shel.myProgram.driver.main(driver.java:24)
  </code></pre>
  
  <p>EDIT: </p>
  
  <p>I'm using this dependency:</p>
  
  <pre><code>    &lt;dependency&gt;
          &lt;groupId&gt;org.apache.poi&lt;/groupId&gt;
          &lt;artifactId&gt;poi-ooxml&lt;/artifactId&gt;
          &lt;version&gt;3.9&lt;/version&gt;
      &lt;/dependency&gt;
  </code></pre>