我希望保存为.rdf文件

代码如下
File file = new File("C:\\ontology.rdf");
FileOutputStream f1 = new FileOutputStream(file);
model.write(f1);

编译的时候总是报错：cannot resolve symbol
                             symbol：f1

然后又改成try{
File file = new File("C:\\ontology.rdf");
   FileOutputStream f1=new FileOutputStream(file);
   RDFWriter d = model.getWriter();
   d.write(model,f1,null);

还是报同样的错
实在不知道怎么改

求助大家，谢谢

import com.hp.hpl.jena.rdf.model.*;
import com.hp.hpl.jena.util.FileManager;

import java.io.*;

public class fileoutput extends Object {

    static final String inputFileName  = "ontology.rdf";
                              
    public static void main (String args[]) {
    
        Model model = ModelFactory.createDefaultModel();

        InputStream in = FileManager.get().open( inputFileName );
        if (in == null) {
            throw new IllegalArgumentException( "File: " + inputFileName + " not found");
        }
        
        
        model.read(new InputStreamReader(in), "");
                    
       
try{
File file=new File("C:\\a.rdf");
   FileOutputStream f1=new FileOutputStream(file);
}catch(Exception e)
{}
   RDFWriter d = model.getWriter();
   d.write(model,f1,null);
                 
    }
}

程序报错
fileoutput.java:31: cannot resolve symbol
symbol :  variable f1
location: class fileoutput
     d.write(model,f1,null);
1 error