Why am I receiving a .class is expected? Trying to call a method in java

Question

I'm pretty new to programming feel free to be harsh in your replies. Anything helps. Basically I'm trying to call in a method LineCount() but when I try to compile the command prompt complains about .class being expected at String[A] (line 8 I believe)

*Thank you guys for all your help! My code works now! I really appreciate all the input

import java.util.Scanner;
import java.io.*;

public class FileCount{

    public static void main(String[] args) throws IOException{

        String[] in = new Scanner(new File(args[0]));
        System.out.println(lineCount(String[] in);

    }

    public static void lineCount(String[] A){

        // check number of command line arguments
        if(args.length != 1){
            System.err.println("Usage: LineCount file");
            System.exit(1);
        }

        // count lines, words, and chars in file
        int lineCount = 0;
        while( in.hasNextLine() ){
            in.nextLine();
            lineCount++;
        }
        in.close();

        System.out.println( args[0]+" contains "+lineCount+" lines" );

    }

}

Answer 1

-> There are many mistakes in your code, Besides other answers want to add that, Since you are passing lineCount(in) as an argument to the linecount() method , then refer to the parameter in lineCount(String[] A) now via A variable and not in.

-> Also you cannot refer to args inside linecount() method since it is a parameter of main() method and hence is limited to it in its scope.

-> You cannot do this String[] in = new Scanner(new File(args[0])); , you are assigning a Scanner instance to an String Array, you have to do it like this

Scanner in = new Scanner(new File(args[0]));

-> You are calling linecount() inside a System.out.println() method , although your method linecount() has a return type of void, Dont put your method inside print() function , because anyways it has got print() statements inside it.

-> Maybe last , there could be more , Since your in variable is of type Scanner , change your method declaration to

 public static void lineCount(Scanner in){

and now call it like lineCount(in) from main().

Edit :- Since you are a beginner i will give you working code for your question:-

import java.util.Scanner;
import java.io.*;

public class FileCount{

    public static void main(String[] args) throws IOException{


      // check number of command line arguments, and check it in main()
       if(args.length != 1){
            System.err.println("Usage: LineCount file");
            System.exit(1);
        }

    Scanner in = new Scanner(new File(args[0]));
    System.out.println( args[0]+" contains "+lineCount(in)+" lines" ); //call this line in main() and not in linecount() as you refer to both args and need the linecount.

    }

    public static int lineCount(Scanner in){


        // count lines, words, and chars in file
        int lineCount = 0;
        while( in.hasNextLine() ){
            in.nextLine();
            lineCount++;
        }
        in.close();

        return lineCount; //return the linecount from method 

    }

}