java - 如何使用缓冲区阅读器跳过注释？

Question

我编写了以下程序来从文件中读取并跳过注释，它适用于单行注释，但不适用于多行注释。有谁知道为什么？我不需要担心字符串中的“//”。并且只有java注释，即“//”和“/* */”

代码:

import java.io.*;

public class IfCounter2 
{   
    public static boolean lineAComment(String line)
    {
        if (line.contains("//"))    
            return true;

        return false;
    }

    public static boolean multiLineCommentStart(String line)
    {
        if (line.contains("/*"))    
            return true;

        return false;
    }

    public static boolean multiLineCommentEnd(String line)
    {
        if (line.contains("*/"))    
            return true;

        return false;
    }

    public static void main(String[] args) throws IOException 
    {
        String fileName = args[0];

        int numArgs = args.length;

        int ifCount = 0;

        // create a new BufferReader
        BufferedReader reader = new BufferedReader(new FileReader(fileName));
        String line = null;
        StringBuilder stringBuilder = new StringBuilder();
        String ls = System.getProperty("line.separator");

        line = reader.readLine();
        // read from the text file
        boolean multiLineComment = false;

        while (( line = reader.readLine()) != null) 
        {
          if (!multiLineCommentStart(line)) 
          {
            multiLineComment = true;
          }

          if (multiLineComment) {
            if (!multiLineCommentEnd(line)) 
            {
              multiLineComment = false;
            }
          }

          if (!lineAComment(line) && !multiLineComment) 
          {
            stringBuilder.append(line);
            stringBuilder.append(ls);
          }
        }


        // create a new string with stringBuilder data
        String tempString = stringBuilder.toString();
        System.out.println(stringBuilder.toString());

    } 
} 

Answer 1

只有当 !multiLineCommentStart(line) 为 true 时，才将 multiLineComment 设置为 true - 也就是说，只要该行不包含 /* .