找到符号 readline 时出错，找不到包

Question

代码，无法理解为什么我们有错误一切看起来都很好。请帮忙import java.io.*;public class ReadKeyboard3{    public static void main(String[] args) throws IOException    {        Scanner scanner = new Scanner(System.in);        BufferedReader in = new BufferedReader(isr);        System.out.print("Enter marks for English: ");        String EnglishMarks = scanner.readline();        int English = Integer.parseInt(EnglishMarks);        System.out.print("Enter marks for Maths: ");        String MathsMarks = in.readLine();        int Maths = Integer.parseInt(MathsMarks);        System.out.print("Enter marks for Science: ");        String ScienceMarks = in.readLine();        int Science = Integer.parseInt(ScienceMarks);        float avg = (English + Maths + Science)/3;        system.out.println("Average of all 3 subjects:" +avg);    }}错误：ReadKeyboard3.java:10: error: cannot find symbol        String EnglishMarks = in.readline();                                ^  symbol:   method readline()  location: variable in of type BufferedReaderReadKeyboard3.java:22: error: package system does not exist        system.out.println("Average of all 3 subjects:" +avg);谁能帮助我理解错误

Answer 1

您尝试调用的实际函数是readLine()(not readline())。同样在第 22 行，使用System而不是system（因为 Java 区分大小写，如注释中所述）此外，对于 using Scanner，您需要导入java.util.Scanner.