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public class Password { 
  public static void changePassword(final String password_file) throws FileNotFoundException {
    FileInputStream fin;
    fin = openPasswordFile(password_file);
  }
	
  public static FileInputStream openPasswordFile(String password_file) throws FileNotFoundException {
    // Declare as final and assign before the body of the anonymous inner class
    // Array f[] is used to maintain language semantics while using final 
    final FileInputStream f[]={null};
    // Use own privilege to open the sensitive password file
    AccessController.doPrivileged(new PrivilegedAction() {
      public Object run() {   
        try {
          f[0] = new FileInputStream("c:\\" + passowrd_file);	//Perform privileged action
        }catch(FileNotFoundException cnf) { System.err.println(cnf.getMessage()); }
        return null;    //Still mandatory to return from run()
      }
    });
   return f[0];  //Returns a reference to privileged objects (inappropriate)
 }	
}

class Password {
  private static void changePassword() {
    // Use own privilege to open the sensitive password file
    final String password_file = "password"; 
    final FileInputStream f[] = {null};
    AccessController.doPrivileged(new PrivilegedAction() {
      public Object run() {
        try {
          f[0] = openPasswordFile(password_file);  // call the privileged method here
        }catch(FileNotFoundException cnf) { 
          System.err.println("Error: Operation could not be performed");
        }
        return null;
      }
    });
    //Perform other operations such as password verification
  }	

  private static FileInputStream openPasswordFile(String password_file) throws FileNotFoundException {
    FileInputStream f = new FileInputStream("c:\\" + password_file);
    // Perform read/write operations on password file
    return f;
  }
}