Help with I/O closing the Reader

[sandyw]

Hi everyone.
I need help I'm trying to close the reader and It wil not let me.
Can some one tell me why and possible show me.

    public static void main(String[] args) throws Exception {
 
        Scanner kbd = new Scanner(System.in);
        int choice;
        System.out.println("Make a Section: ");
        System.out.println("1. Read Text File ");
        System.out.println("2. Copy Text File ");
        System.out.println("3. Exit ");
        System.out.print("\nPlease press Enter afer each response");
        System.out.println("Enter your choose please: ");
        choice = kbd.nextInt();
        kbd.nextLine();
        if (choice == 1) { // if 1 is select go to makePerson
 
 
            String reader;
            String name = null;
            kbd = new Scanner (new File(name));
 
try{
 
            System.out.print( "Enter the filename you want to open  " );
            name = kbd.nextLine();
 
             while (kbd.hasNext())
             {
                 reader = kbd.nextLine();
                System.out.println ( reader);
                System.out.println();
             }
             }finally{
                 if (name !=null){
                 name.close();
             }
             }
          }

Thanks
sandyw

[JosAH]

Variable 'name' is a String; you can't close Strings. Your compiler must've said
something like "close is not a String method". Try to read those compiler error
diagnostics.

kind regards,

Jos

[sandyw]

Thanks figure that out.
But what My real task to figure out is
I need a scanner what will prompt the user to type in a file they are looking for on a hard drive (C:\\ ...) then display that file.

I have found some info on this but I lose and confused on how to tie everything together.

I have these codes so far.
This one to read the file with FileReader.

import java.io.*;
import java.util.Scanner;
 
public class ScanXan {
    public static void main(String[] args) throws IOException {
        Scanner s = null;
        try {
            s = new Scanner(new BufferedReader(new FileReader("xanadu.txt")));
 
            while (s.hasNext()) {
                System.out.println(s.next());
            }
        } finally {
            if (s != null) {
                s.close();
            }
        }
    }
}

This one for Scanner prompt...

public static void main(String[] args) throws Exception {
        Scanner kbd = new Scanner(System.in);
        int choice;
        System.out.println("Make a Section: ");
        System.out.println("1. Read Text File ");
        System.out.println("2. Copy Text File ");
        System.out.println("3. Exit ");
        System.out.print("\nPlease press Enter afer each response");
        System.out.println("Enter your choose please: ");
        choice = kbd.nextInt();
        kbd.nextLine();
        if (choice == 1) { // if 1 is select go to makePerson
            String fname;
 
            FileInputStream fin;
 
            long datalen=0;
 
            Scanner kbd1 = new Scanner(System.in);
 
            System.out.println("Enter file name");
 
            fname = kbd1.next();
 
            kbd1.nextLine(); 
 
            fin = new FileInputStream(fname);
 
            while( fin.read()!=-1) {
 
                      datalen++;
 
            }
 
            System.out.println("File "+fname+" is "+datalen+" bytes long");
 
  }

SandyW

[JosAH]

I get the impression that you are googling for snippets of code and that you are
trying to glue those together without understanding what you're doing.

The snippets your showed in your last reply show different indentation style and,
more important, different coding stye, and most important: they don't do what
your assignment says they should do. And no wonder: those snippets weren't
made for those purposes.

Chop up your problem to smaller sub-problems, Try to write a method first that
opens a file, reads all the lines and display every line. Finally the method should
close the resources again. Hint: read the API documentation for the Buffered-
Reader and pay close attention to its readLine() method. And please *read* the
API documentation.

kind regards,

Jos

[sandyw]

You are right jos,
I'm doing this for fun....
here is what I have now
Sorry its a learning process...

Getting an error on s1.close();
with is error
Exception in thread "main" java.lang.NullPointerException
at ioassign.ReadCopy.main(ReadCopy.java:54)

    public static void main(String[] args) throws Exception {
        Scanner kbd = new Scanner(System.in);
        int choice;
        System.out.println("Make a Section: ");
        System.out.println("1. Read Text File ");
        System.out.println("2. Copy Text File ");
        System.out.println("3. Exit ");
        System.out.print("\nPlease press Enter afer each response");
        System.out.println("Enter your choose please: ");
        choice = kbd.nextInt();
        kbd.nextLine();
        if (choice == 1) { // if 1 is select go to makePerson
            String fname;
 
            FileInputStream fin = null;
 
            long datalen=0;
 
            Scanner kbd1 = new Scanner(System.in);
 
            System.out.println("Enter file name");
 
            fname = kbd1.next();
 
 
 
 
            Scanner s1 = null;
 
                    try {
                        s1 = new Scanner(new BufferedReader(new FileReader("fname")));
 
            while( fin.read()!=-1) {
 
                      datalen++;
 
            }
 
            System.out.println("File "+fname+" is "+datalen+" bytes long");
            System.out.println("File "+s1+" is "+datalen+" bytes long");
                    }finally{
                        if (fname !=null){
                            s1.close();
                        }
                    }
  }

thanks
Sandyw
PS I hope you don't mind helping me.

[JosAH]

Getting an error on s1.close();
with is error
Exception in thread "main" java.lang.NullPointerException
at ioassign.ReadCopy.main(ReadCopy.java:54)

            String fname;
   ...
            Scanner s1 = null;
 
                    try {
                        s1 = new Scanner(new BufferedReader(new FileReader("fname")));
 
   ...
                    }finally{
                        if (fname !=null){
                            s1.close();
                        }
                    }
  }

I suggest you should read some tutorials first. This code just doesn't make
sense and there are so many errors in it I hardly know where to start. For
one thing, what are those double quotes doing there in "fname"? Most likely
a file named "fname" doesn't exist so the entire opening sequence will fail
so the Scanner s1 will be null (you don't even use it at all) and hence the
closing will fail too. Everything fails in that messy code.

Take it from me: study those tutorials first so that you *know* what you're doing.
Glueing code snippets together by trial and error is not the way to go. I wish you
all the best studying the tutorials. Here's the link.

kind regards,

Jos

[NeoPa]

Sandy,
I'm just visiting from another forum, but it seems to me that Jos is actually being very helpful here.
It seems like you're new to this so Jos is pointing you in the best direction for getting up and running, while giving you some very useful tips on how to find problems in your code on the way.

We don't do the work for people here. We try to help members to learn and hold their hands through the harder bits where necessary. Jos is very experienced and I strongly recommend that you follow the instructions he's posted for you in posts #2, 4 & 6. If you can show that you've taken those steps then I'm sure he can take you further.

Best regards -NeoPa.

[JosAH]

*blush* ;-)

kind regards,

Jos