java - 方法的表达式开头非法

Question

下面是一些代码，尝试查找超过一定数量字符的第一个单词。

public class FirstMatch {
    public static void main(String[] args) throws java.io.FileNotFoundException {
        Scanner in = new Scanner(new FileReader("aliceInWonderland.txt"));
        String longWord = "";
        boolean found = false;

        public void threshold (int Threshold) {
            while (in.hasNext() && !found) {
                String word = in.next();
                if (word.length() > Threshold) {
                    longWord = word;
                    found = true;
                }
            }
            System.out.println("The first long word is: " + longWord);
        }
    }
}

(在上面的代码中我没有复制所有的导入语句)由于某种原因，我的阈值方法它返回非法的表达式开始。我认为这是一个愚蠢的错误，但无法弄清楚出了什么问题......

Answer 1

您应该在 main 方法之外声明您的 threshold 方法。

方法只能在类级别创建，而不能在另一个方法内创建。

import java.io.FileReader;
import java.util.Scanner;

public class FirstMatch {

    public static void main(String[] args) throws java.io.FileNotFoundException {
        Scanner in = new Scanner(new FileReader("aliceInWonderland.txt"));    
        threshold(in, 10);
    }

    public static void threshold(Scanner in, int threshold) {
        String longWord = "";
        boolean found = false;
        while (in.hasNext() && !found) {
            String word = in.next();
            if (word.length() > threshold) {
                longWord = word;
                found = true;
            }
        }
        System.out.println("The first long word is: " + longWord);
    }

}