Question

我正在尝试读取文本文件并创建一个对象数组。我一直收到以下错误......

Exception in thread "main" java.util.NoSuchElementException
at java.util.Scanner.throwFor(Unknown Source)
at java.util.Scanner.next(Unknown Source)
at Prog6.main(Prog6.java:33)

它没有读取字段，我已经尝试了一切我能想到的解决方法。这是代码。任何意见，将不胜感激。谢谢！

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

public class Prog6
{
public static void main(String[] args)
{
    String fname;
    String lname;
    String team; 
    String position;
    int completions;
    int attempts;
    int yards; 
    int receptions;

    Scanner inFile = null;
    Report rep = new Report();

    /*
     * Open File
     */
    try
    {
        inFile = new Scanner( new File( "nfl.txt" ) );
    }
    catch ( FileNotFoundException e )
    {
        System.err.println( "Error: file not found" );
    }
    /*
     * Read file
     */

    while (inFile.hasNext())
    {
        fname = inFile.next();
        lname = inFile.next();
        team = inFile.next();
        position = inFile.next();
        if (position == "QB")
        {
            completions = inFile.nextInt();
            attempts = inFile.nextInt();
            yards = inFile.nextInt();
            Player qb = new Player ();

            rep.addQuarterback(qb);
        }
        else if (position == "WR")
        {
            receptions = inFile.nextInt();
            yards = inFile.nextInt();
            Player wr = new Player ();

            rep.addReceiver(wr);
        }

        // Print report

        rep.printReport();      
    }


}
}

Answer 1

由于某种原因，读入的行没有您认为的那么多项目。扫描仪有一组hasNext方法（如long值的hasNextLong（）），它们告诉您是否有下一个要扫描的项目以及该项目的格式是否正确。在获取下一个项目之前使用这些方法，您可以避免错误。

Answer 2

你可能想要“while”循环，你试图在“try”循环中读取inFile。

如果我没错，那么文件会在此之后关闭，因此您无法真正调用扫描程序。

所以，你会去：

try {
     inFile = new Scanner(new File("nfl.txt"));        
     while(inFile.hasNext()) {    
         .....      
         ..... 
} catch

无法读取Java文本文件

2 个答案: