Adding rows to an excel spreadsheet using apache poi

In a recent project for a client I was tasked with modifying an existing excel spreadsheet to add data from a query. Being familiar with Java and ColdFusion I assumed this would be a pretty trivial exercise. Read the existing file, get the sheet and then write the data, but I ran into an issue where adding rows using shiftRows didn’t make them writable and/or visible to apache poi. I realized I needed to literally add the rows and the columns to the excel spreadsheet to be able to change the values. Not a big deal code-wise and also really fast to complete, but frustrating to figure out.

currentCharterTemplate = 'existingWorkbook.xlsx';
currentFilePath = getDirectoryFromPath(getCurrentTemplatePath());
javaFile = createObject('java', 'java.io.File').init(currentFilePath & currentCharterTemplate);
excelFile = createObject('java', 'java.io.FileInputStream').init(javaFile);
xssfWorkbook = createObject('java', 'org.apache.poi.xssf.usermodel.XSSFWorkbook').init(excelFile);

summarySheet = xssfWorkbook.getSheetAt(0);
totalColumns = 12;
rowsToAdd = query.recordCount;
//add enough rows/columns to the spreadsheet to handle the record count of the query and the sort fields
for (rows = 1; rows <= rowsToAdd; rows++) {
  summarySheet.createRow(rows);
  theCurrentRow = summarySheet.getRow(rows);
  for (columns = 0; columns <= totalColumns; columns++) {
    theCurrentRow.createCell(columns);
    theCurrentRow.getCell(columns);
  }
}
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About Matt Busche

Matt is a developer at Nationwide Insurance and Freelance Consultant.

Des Moines, IA https://www.matthewbusche.com