Passing a filename as parameter in core java?

Question

Hi All,
Instead of using a hardcoded filename i want to use a filename as
parameter so that i can include any file without hardcoding it.For eg,
Here is my sample code:-
import java.io.*;
class ParameterFile
FileInputStream fin;
public void open( String source) throws IOException
fin=new FileInputStream(source); //The filename should be included instead of a hardcoded one.
          BufferedReader br=new BufferedReader(new InputStreamReader(fin));
          String line="";
          while(((line=br.readLine())!=null))
          System.out.println(line);
          fin.close();
public static void main(String args[])
try
File source=new File(args[0]);//passing the filename as commandline argument
ParameterFile pf=new ParameterFile();
pf.open(source);
}catch(IOException ee)
Here when i run the program i want to pass the filename in commandline argument.Like java ParameterFile Readme.txt.
Here it is giving an error in pf.source(source)saying cannot resolve symbol.What is the problem here pls. do rectify it.
Thanx,
m.ananthu

Answer 1

public void open( String source) throws IOException <--- you put String type as your parameter in the "open" method.
File source=new File(args[0]);//passing the
the filename as commandline argument
ParameterFile pf=new ParameterFile();
pf.open(source); <---- but you pass in your parameter using File type...so, java compiler cannot find a method which take File as the parameter.
try change
public void open( String source) throws IOException
to
public void open(File source) throws IOException