Thread: How to change File Type of a File Using java

Did you just want to rename the file? If so, the File class has a method for renaming a file:

// File (or directory) with old name
File file = new File("oldname");
// File (or directory) with new name
File file2 = new File("newname");
// Rename file (or directory)
boolean success = file.renameTo(file2);
if (!success)
{
// File was not successfully renamed
}

Hello akash169.

Please only post in the correct forum. There is no point posting 3 of the same threads. We will answer you as quickly as possible regardless. It just creates more work for us having to remove the extra threads.

Isn't changing the extension name, technically changing the type?

Please post your code so we can try it..

Hi,

I am sorry for posting the same in three places. I have attached the actual excel document i use with this code. Also to run this code without compilation errors, you will need the POI Api Jar file. I tried to attach the POI zip with this post, but the size limit restricts me in doing so. So the .xls file has the type webpage(*.htm, *.html). If you run this code with this file you will get an error, but if you open the file manually, change the type to Excel workbook using the file Save-As Dialog and re-run this program it displays the cell content correctly.

So is there a way in java, i can open the file change the file type to Excel Workbook(*.xls) and then run my program?

public class Excel_Read extends Excel_ReadHelper
{
 
      public void testMain(Object[] args) 
 
      {
             try{
                  // This is where my file resides, please change this based on your local directory pat			
                    InputStream ins = new FileInputStream("\\\\QA\\Projects\FileName.xls") ;  
		POIFSFileSystem fs = new POIFSFileSystem(ins); 
		HSSFWorkbook wb     = new HSSFWorkbook(fs);
		HSSFSheet sheet = wb.getSheetAt(0);       // first sheet
		HSSFRow row     = sheet.getRow(0);        // eighth row
		HSSFCell cell   = row.getCell((short)0);  // first cell
 
		String cellcontent = cell.toString();
		System.out.println(cellcontent); // Display The Value of the First Cell
		}
		catch(FileNotFoundException e)
		{
		System.out.println(e.getMessage());
		}
 
		catch(Exception r)
		{
			System.out.println(r.getMessage());
 
		}
 
 
	}
}

Opening via the Java File class always includes the extension. Only windows explorer will try to hide the extension (if the setting is on).

The only way to change the type of a file is to open that file up with the original type, then save out to a file that has the new type you want.