Question

我正在尝试创建一个导入文本文件的程序并对其进行分析，以告诉我其他文本文件是否有匹配的句子。导入文件并尝试分析时，我一直遇到此错误。我假设我在代码中遗漏了一些内容。

Exception in thread "main" java.util.NoSuchElementException
at java.util.Scanner.throwFor(Scanner.java:907)
at java.util.Scanner.next(Scanner.java:1416)
at PossibleSentence.main(PossibleSentence.java:30)

也是我的代码：

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

public class PossibleSentence {
   public static void main(String[] args) throws FileNotFoundException{       
      Scanner testScan = new Scanner(System.in);
      System.out.print("Please enter the log file to analyze: ");
      String fileName = testScan.nextLine();

      File f = new File(fileName);
      Scanner scan = new Scanner(f);
      String line = null;
      int i = 0;

      while (scan.hasNextLine()) {
         String word = scan.next();
         i++;
      }

      scan.close();

      File comparative = new File("IdentifyWords.java");
      Scanner compare = new Scanner(comparative);
      String line2 = null;
   }
}

我还没完成第二台扫描仪。有什么建议吗？

Answer 1

我们需要更多信息才能最终回答，但请查看the documentation for next()。当没有下一个元素时，它会抛出此异常。我的猜测是因为这部分：

String fileName = testScan.nextLine();

您不是先检查是否hasNextLine。

Answer 2

您正在将文件参数传递给Scanner对象，请尝试使用InputStream

File input = new File(/* file argument*/);
BufferedReader br = null;
FileReader fr= null;
Scanner scan = null;
try {
    fr = new FileReader(input);
    br = new BufferedReader(fr);
    scan = new Scanner(br);
    /* Do logic with scanner */
} catch (IOException e) {
    /* handling for errors*/
} finally {
    try {
        if (br != null) {
            br.close();
        }
        if (fr != null) {
            fr.close();
        }
        if (scan != null) {
            scan.close();
        }
    } catch (IOException e) {
        /* handle closing error */
    }
}

扫描导入文件的Java异常

2 个答案: