我如何让我的Java扫描仪从此文件中读取这些字符串？

Question

我有这个输入文件：

6
8
ABBEJCDD
ULSCALAR
FUGLVRUT
STOUASTO
STOALGOT
LALGOSLU
8
SCALA
JAVA
ALGOS
ALGORITHM
SLUG
SLUR
GOES
TURTLE

当前，我正在做的是读取前两个项目（即int），并将它们添加到ArrayList中。 然后，我只想读取接下来的6行（不包括“ 8”），并将它们添加到数组中。

我将如何修改我的代码？

    Scanner fileScanner = null;
    File inFile = new File("input.dat");

    ArrayList<Integer> rc = new ArrayList<Integer>();

    try {
        fileScanner = new Scanner(inFile);
        System.out.println("The input has been loaded successfully.");

        while (fileScanner.hasNextInt()) {
            int tempRowsCols = fileScanner.nextInt();
            rc.add(tempRowsCols);
        } // end while

        while (fileScanner.hasNext()) {
            System.out.print(fileScanner.next());
        }
    } // end try

    catch (Exception e) {
        System.out.println("Did not work.");
    }

Answer 1

这个问题希望代码以其他方式读取数据。 假设前两个值是整数，分别表示文本网格的高度和宽度。

// read the width and height
int height = scan.nextInt();
int width = scan.nextInt();
// build the 2D array to store the char grid.
char[][] chars = new char[height][];
for (int line = 0; line < height; line++) {
    chars[line] = scan.next().toCharArray();
}

然后，您得到8来指示有8个单词，然后是单词：

// get the number of words to expect
int wordcount = scan.nextInt();
// make a place to store the words.
String[] words = new String[wordcount];
for (int i = 0; i < wordcount; i++) {
    words[i] = scan.next();
}

这将为您提供2d char数组中的数据，以及String数组中的单词。

Answer 2

嗯，您的问题有点含糊，但这是您想的吗？ 我看不到ArrayList<Integer>的用途，所以我直接读取行和列：

try {
        fileScanner = new Scanner(inFile);
        System.out.println("The input has been loaded successfully.");

        String rows = fileScanner.next();   // read the number of rows
        String cols = fileScanner.next();   // read the number of columns
        String token = fileScanner.next();  // read next token
        System.out.println("\n\tROWS (" + rows + ")\n");
        while (!token.equals(cols)) {  // while token doesn't equal to the number of columns, keep read tokens
            System.out.println("\t" + token);
            token = fileScanner.next();
        }
        int colsInt = Integer.parseInt(token); // get number of columns as an int
        System.out.println("\n\tCOLS (" + cols + ")\n"); // read that many tokens
        for (int i = 0; i < colsInt; i++) {
            System.out.println("\t" + fileScanner.next());
        }
    } // end try

OUTPUT：

ROWS (6)

ABBEJCDD
ULSCALAR
FUGLVRUT
STOUASTO
STOALGOT
LALGOSLU

COLS (8)

SCALA
JAVA
ALGOS
ALGORITHM
SLUG
SLUR
GOES
TURTLE

请注意，如果您的文件不是这种格式，则此代码将中断。

通常，如果您不知道要读取多少个int或Strings ，则可以进行一个循环，然后一次读取一个标记，然后根据它是String还是int执行适当的操作：

while(fileScanner.hasNext() {
    if(fileScanner.hasNextInt()) {
        // process int
    } else {
        // process string
    }
}

Answer 3

ArrayList<String> fileStrings = new ArrayList<String>();
FileInputStream fis = new FileInputStream("file.txt");
BufferedReader reader = new BufferedReader(fis);
while((String tempVar = reader.readLine()) != "8")   // or whatever you want your reader to stop at
{
  fileStrings.add(tempVar);
}

for(String x : fileStrings) System.out.println(x);