Java.在一个文件(记事本)中读取二维数组

Question

示例我在我的文件(记事本)中有这些数字或数组

2 3 4 5 7 2 6 2

2 4 6 8 9 4 8 1

我想问一下如何读取下一行。我只能用这段代码读取第一行。

    String path = "/path/notepad.txt";
    String stringOfNumbers[];
    BufferedReader br = new BufferedReader (new InputStreamReader(System.in));
    BufferedReader br2 = new BufferedReader (new FileReader(path));
    String lineOfNumbers = br2.readLine();
    stringOfNumbers = lineOfNumbers.split(" ");
  //stringOfNumbers = lineOfNumbers.split("n");
    String str = lineOfNumbers.replace(","," ");
    System.out.println(str);
    System.out.print("");

    int numbers[][] = new int [stringOfNumbers.length][stringOfNumbers.length];
    for (int i = 0; i < numbers.length; i++)
    {
        numbers[i][i] = Integer.parseInt(stringOfNumbers[i]);
    }
    System.out.print("Enter the number to search:   ");
    int searchNumber = Integer.parseInt(br.readLine());
    int location = 0;
    for (int i = 0; i < numbers.length; i++)
    {
        if (numbers[i][i] == searchNumber)
        {
            location = i+ 1;
        }
    }

提前感谢。

Answer 1

我会这样做

FileReader fr = new FileReader("myFileName");
BufferedReader br = new BufferedReader(fr);
while((line=br.readLine())!=null) // as  long as there are lines in the file
{
  stringOfNumbers = line.split(" ");
// other code
}

Answer 2

以下代码将帮助您将文件中的所有数字保存到内存

Scanner scanner = new Scanner(path);
List<Integer[]> integerArList = new ArrayList<Integer[]>();
while(scanner.hasNextLine()){
String lineOfNumbers = scanner.nextLine();

        stringOfNumbers = lineOfNumbers.split(" ");
        //stringOfNumbers = lineOfNumbers.split("n");
        String str = lineOfNumbers.replace(","," ");
        System.out.println(str);
        System.out.print("");

    Integer[] numbers = new Integer[stringOfNumbers.length];
    for (int i = 0; i < numbers.length; i++)
    {
        numbers[i] = Integer.parseInt(stringOfNumbers[i]);
    }
    integerArList.add(numbers);
}

在此之后，您可以通过遍历List中的每个数组来搜索任何整数，如下所示:

int searchMe = <get this from user>
int location=0;
boolean found=false;
for(Integer[] intAr: integerArList){
    for(int i=0;i<intAr.length;i++){
        if(intAr[i]==searchMe){
            location+=(i+1)
            found=true;
            break;
        }
    }
    if(found) break;
    location+=intAr.length;
}
System.out.println("Location of " + searchMe +" : " +(found?location:"Not Found in Data"));

Answer 3

要读取文本文件的所有行，可以这样做:

    String path = "/path/notepad.txt";
    String stringOfNumbers[];
    BufferedReader br = new BufferedReader (new InputStreamReader(System.in));
    BufferedReader br2 = new BufferedReader (new FileReader(path));
    ArrayList<String> listOfLines = new ArrayList<String>();
    //String lineOfNumbers = "";
    String line = "";
    String allIndexes = "";
    while ((line = br2.readLine()) != null) {
        if(!line.isEmpty()){
            listOfLines.add(line);
        }
    }
    for(String lineOfNumbers : listOfLines){
        stringOfNumbers = lineOfNumbers.split(" ");
          //stringOfNumbers = lineOfNumbers.split("n");
        String str = lineOfNumbers.replace(","," ");
        System.out.println(str);
        System.out.print("");
        int numbers[][] = new int [stringOfNumbers.length][listOfLines.size()];
        for (int i = 0; i < numbers.length; i++)
        {
            numbers[i][listOfLines.indexOf(lineOfNumbers)] = Integer.parseInt(stringOfNumbers[i]);
        }
        System.out.print("Enter the number to search:   ");
        int searchNumber = Integer.parseInt(br.readLine());
        int locationI = 0;
        int locationJ = 0;
        for (int i = 0; i < numbers.length; i++)
        {
            for(int j = 0; j < listOfLines.size(); j++)
                if (numbers[i][j] == searchNumber)
                {
                    locationI = i + 1;
                    locationJ = j + 1;
                    allIndexes += locationI + ":" + locationJ + " ";
                }
        }
    }