異常處理和IO

Question

因此，我創建了一個程序，該程序載入具有以下格式的文件：John 55 18.27然後將這三個變量（一旦拆分）傳遞到新創建的文件中。

我得到一個異常錯誤1）傑克·特納44 19.22 & 2）邁克55.0 23.44 第一個錯誤是因爲姓，另一個是像55.0 整我怎樣才能解決我的代碼來處理這些異常？

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


public class methods { 
    private String name; 
    private int hours; 
    private double timeSpent; 
    private double averageGPA; 

    private Scanner x; 
    private StringTokenizer stk; 
    private String[] storage = new String[11]; 
    private Formatter file; 

    public void openFile(){ 
     try{ 
      x = new Scanner(new File("students.dat")); 
     } 
     catch(Exception e){ 
      System.out.println("could not find file"); 
     } 
    } 

    public void readFile(){ 
     int count = 0; 
     while(x.hasNext()){ 

      storage[count] = x.nextLine(); 
      count ++; 
     } 
    } 

    public void closeFile(){ 
     x.close(); 
    } 

    public void stringTokenizer(){ 
     int count = 0; 
     createNewFile(); 
     while(count < storage.length){ 

     stk = new StringTokenizer(storage[count]); 
     name = stk.nextToken(); 
     hours = Integer.parseInt(stk.nextToken()); 
     timeSpent = Double.parseDouble(stk.nextToken()); 
     addRecords(); 
     count++; 

     } 
     file.close(); 

    } 

    public void createNewFile(){ 
     try{ 
      file = new Formatter("skeleton.txt"); 
     } 
     catch(Exception e){ 
      System.out.println("There has been an error"); 
     } 
    } 

    public void addRecords(){ 
     file.format("%s %s %s\n", name, hours, timeSpent); 
    } 

} 

公共類Lab1_a {

public static void main(String[] args) { 
    int creditHrs;  // number of semester hours earned 
double qualityPts; // number of quality points earned 
double gpa;  // grade point (quality point) average 

String line, name = "", inputName = "students.dat"; 
String outputName = "warning.dat"; 

    //Get File 
    methods obj1 = new methods(); 


    //Create an Array of Strings 
    obj1.openFile(); 
    obj1.readFile(); 



    obj1.createNewFile(); 
    obj1.stringTokenizer(); 
    obj1.closeFile(); 
} 

}

Answer 1

首先，閱讀name後，如果下一個標記不能被解析爲double，它與之間的空間追加到name。繼續，直到找到double。

一旦找到第一個double，將其轉換爲int並存儲爲hours。

解析timeSpent像以前一樣。

這裏的一些（未經測試）的代碼，應該讓你開始：

name = stk.nextToken(); 
String next; 
while (true) { 
    try { 
     next = stk.nextToken(); 
     hours = (int)Double.parseDouble(next); 
     break; 
    } catch (NumberFormatException e) { 
     name = name + " " + next; 
    } 
} 
timeSpent = Double.parseDouble(stk.nextToken());