系统扫描仪，用于循环格式的整数和单词

Question

I am currently taking a computer science class in high school, and its my first time programming (2 weeks since i started). I have currently finished my program however there were a few details that bothered me. I was supposed to create a program which can calculate average of individual marks and then calculate all of the average marks previously entered by user. However I noticed something that bothered me, which was the fact that if i were to enter a number when asked to enter a name, it would assume that number is a name. Also when I asked for the 5 marks the program would run fine until an error occurs if i accidentally type in a letter or word. I have done some research and found system scanners however i still don't understand the concept in a looping situation. Here is what I have so far. Any advice or explanation on how to correct this would be appreciated!

import java.io.*;
public class loopingEx6Final {
    public static void main(String args[]) throws IOException{
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        double average, totalaverage = 0;
        int Mark, Marktotal=0,  marktotalsum=0, count=0;
        String strName, strMark;
        System.out.println("This program will calculate an individual's personal average and then calculate the class average whn instructed.");
        System.out.println("Please type (finish) in order to calculate class average.");
        System.out.println("Please enter a name.");
        strName = br.readLine ();

        while (!strName.equals("finish")){
            System.out.println("The follwing will calculate the average five marks of "+ strName +".");
            System.out.println("Please enter 5 marks.");
            count++;
            for  (int i=0;i<5;i++) {
                Mark = Integer.parseInt(br.readLine());
                    Marktotal= Marktotal + Mark;        

            }
            average = Marktotal/5;
            System.out.println(strName+"'s average is "+average);
            Marktotal= 0;
            System.out.println("\n"+"Please enter a name.");
            strName = br.readLine ();
            totalaverage=(totalaverage+average)/count;
        }       
        System.out.println("The class average of all input grades is:");
        System.out.println(totalaverage);
        System.out.println();
        System.out.println("Thank you for using the program.");
    }
}

Answer 1

With the Scanner in java.util.* you can do something like this to read your inputs for marks.

Scanner inputs = new Scanner(System.in); // instead of Buffered Reader
int marks, total;
for(int i=0; i<5; i++){
    if(inputs.hasNext()){                // if the input is an integer
        marks = inputs.nextInt();        // use the input
        total += marks;
    } else {
        inputs.readLine();               // read the invalid int input and ignore
        i--;                             // iterate the loop for once more
    }
}

You can use inputs.readLine(); to read a string input..

If you need more references on Scanner.. Try
http://www.java-made-easy.com/java-scanner.html
http://docs.oracle.com/javase/7/docs/api/java/util/Scanner.html