语法Java：如何判断文本文件中的一行是否应该为空？

Question

我正在做一个项目，我必须读入一个语法文件（将它分解成我的数据结构），目标是能够生成一个随机的“DearJohnLetter”

我的问题是，当在教室里看书时。txt文件，我不知道如何找出该文件是否应该是一个完全空白行，这是有害的程序

下面是一个文件部分的示例，如何判断下一行是否应该是空行？（顺便说一句，我只是使用一个缓冲阅读器）谢谢

---

<start>
I have to break up with you because <reason> . But let's still <disclaimer> .

<reason>
<dubious-excuse>
<dubious-excuse> , and also because <reason>

<dubious-excuse>
my <person> doesn't like you
I'm in love with <another>
I haven't told you this before but <harsh>
I didn't have the heart to tell you this when we were going out, but <harsh>
you never <romantic-with-me> with me any more
you don't <romantic> any more
my <someone> said you were bad news

Answer 1

如果我没弄错的话，你只想在一行中确定下一行是否为空

如果为真，那么这里有一个启动示例：

package com.stackoverflow.q2405942;

import java.io.BufferedReader;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStreamReader;

public class Test {

    public static void main(String... args) throws IOException {
        BufferedReader reader = null;
        try {
            reader = new BufferedReader(new InputStreamReader(new FileInputStream("/test.txt")));
            for (String next, line = reader.readLine(); line != null; line = next) {
                next = reader.readLine();
                boolean nextIsBlank = next != null && next.isEmpty();
                System.out.println(line + "   next line is blank: " + nextIsBlank);
            }
        } finally {
            if (reader != null) try { reader.close(); } catch (IOException logOrIgnore) {}
        }
    }

}

这将打印以下内容：

<start>   next line is blank: false
I have to break up with you because <reason> . But let's still <disclaimer> .   next line is blank: true
   next line is blank: false
<reason>   next line is blank: false
<dubious-excuse>   next line is blank: false
<dubious-excuse> , and also because <reason>   next line is blank: true
   next line is blank: false
<dubious-excuse>   next line is blank: false
my <person> doesn't like you   next line is blank: false
I'm in love with <another>   next line is blank: false
I haven't told you this before but <harsh>   next line is blank: false
I didn't have the heart to tell you this when we were going out, but <harsh>   next line is blank: false
you never <romantic-with-me> with me any more   next line is blank: false
you don't <romantic> any more   next line is blank: false
my <someone> said you were bad news   next line is blank: false