Whether you have balance sheets, account information downloads, tax calculations, or pay slips, they all tend to come in Microsoft Excel. Non-IT professionals feel comfortable using Microsoft Excel as a data exchange technology. The Jakarta POI (Poor Obfuscation Implementation) API is a fantastic way for Java programmers to access Microsoft document formats. The most mature API from Jakarta POI is the HSSF (Horrible Spreadsheet Format) API, which accesses Microsoft Excel documents.
In this article, I walk you through the steps for creating and reading Excel documents, and for using fonts and cell styling—all using Java.
Note: You can download the source code for all the examples in this article from Resources.
The key terms associated with Jakarta POI are as follows:
The Jakarta POI API can be used to create an Excel document programmatically. The important steps involved are:
HSSFWorkbook workbook = new HSSFWorkbook();HSSFSheet sheet = workbook.createSheet("Java Excels");HSSFRow row = sheet.createRow((short)0);HSSFCell cell = row.createCell((short) 0);cell.setCellValue("Have a Cup of XL");workbook.write(fileOutputStream);In this example, you'll see how to read values from an Excel document.
Let's assume this is our Excel sheet:
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The key steps in reading the Excel sheet are as follows:
HSFWorkbook workbook = new HSSFWorkbook(new FileInputStream(fileToBeRead));.
HSSFSheet sheet = workbook.getSheetAt(0);. A sheet can also be referred to by name. Let's assume that the Excel sheet has the default name "Sheet1". It can be referred
to as follows: HSSFSheet sheet = workbook.getSheet("Sheet1");.
HSSFRow row = sheet.getRow(0);.
HSSFCell cell = row.getCell((short)0);.
cell.getStringCellValue();.
Now let's assume that we want to see the list of all declared methods and member variables in a jar file. It would be ideal to have a consolidated list of all information in one single file. We would like to view the information so that the class names are in the first column, declared fields in the second column, and declared methods in the third column, with the column headings appearing in red.
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the exampleBy Anonymous on October 25, 2009, 12:32 pmWhat does this example do? I need to open it as an applet or a swing application.
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Read Excel In JavaBy Anonymous on May 30, 2009, 10:51 pmCheck this article on this: http://knowledge.elementfx.com/java_api/read_excel_in_java.html
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Problem with the above codeBy Anonymous on May 26, 2009, 5:33 amWhen I tried to use the above code in my application I got an applet alert saying - "The applet is trying to access system properties" with allow, disallow, stopapplet...
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All I neededBy Anonymous on March 19, 2009, 11:21 pmThis was all I needed to read Excel worksheets into Java, free my users from the aggravation of needing to create .csv files.
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Very helpful articleBy Anonymous on October 22, 2008, 3:35 amI found this article is very helpful. Apache POI is no doubt a great release which has made the life of a java developer easy. ============================================ All...
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