用Java-12读取文本文件

Question

想一想一个文本文件，比如：

line1 ->5
line2 ->A 10
line3 ->B 15
line4 ->C 25
line5 ->D 5
line6 ->E 30

'5‘是{a，b，c，d，e}的数。如何将这些变量保存在两个数组中，如：

Array1[5] = {A,B,C,D,E}
Array2[5] = {10,15,25,5,30}

Answer 1

// read all lines in the file into a list
List<String> lines = Files.readAllLines(Paths.get("filename"), Charset.defaultCharset());

// determine the length of the arrays based on the first line
int length = Integer.parseInt(lines.remove(0));    

// first column
String[] col1 = new String[length];

// second column
int [] col2 = new int[length];

// now for every remaining row, add to each column
for(int i = 0; i < length; i++){
   String [] pair = lines.remove(0).split(" ");
   col1[i] = pair[0];
   col2[i] = Integer.parseInt(pair[1]);
}

或者更容易..。

// create a scanner of the file
Scanner scan = new Scanner(new File("filename"));

// read the first token as an int to know array length
int length = scan.nextInt();

String [] col1 = new String[length];
int [] col2 = new int[length];

// assuming valid data, loop through each row
for(int i = 0; i < length; i++){
  col1[i] = scan.next();
  col2[i] = scan.nextInt();
}

Answer 2

// x=文件的内容

while(x.hasNext) {
   String a = x.next(); // This will get the first bit (e.g A, B, C, etc)
   String b = x.next(); // This will get the last bit (e.g 10, 15, 25, etc)
   // now just put them in the array
   // for every extra bit of data you have on a line you just add another String y = x.next();
}

在将它们放到数组中之后，它将转到下一行。应该以你想要的方式读你的文件。