java - 正则表达式将所有内容匹配到一个空行

Question

我已经尝试了几个小时，我确信我遗漏了一些简单的东西。我正在尝试在 Java 中创建一个方法，该方法接受一些文本并提取其中的一部分。

我想匹配从“注释”到此后的第一个空行的所有内容

示例输入

Some info about stuff
Notes: THis is a note about other stuff
So is this
    And this

This is something else

输入可以是不同的长度，所以也可以是

  BLabla
    Notes: Hello hello
        So is this
            And this
    And this too
    also

 Now I have something else to say

需要的输出:示例 1

Notes: THis is a note about stuff
So is this
    And this

示例 2

 Notes: Hello hello
        So is this
            And this
    And this too
    also

我试过:

public static String NotesExtractor(String str){
        String mynotes=null;
        str=str+"\n\n"+"ENDOFLINE";
        Pattern Notesmatch_pattern = Pattern.compile("Notes:(.*?)^\\s*$",Pattern.DOTALL);
        Matcher Notesmatchermatch_pattern = Notesmatch_pattern.matcher(str);
        if (Notesmatchermatch_pattern.find()) {     
        String h = Notesmatchermatch_pattern.group(1).trim();
        mynotes=h;

    }
        mynotes=mynotes.replaceAll("^\\n", "").trim();
        return mynotes;

    }

但我没有得到任何匹配，我不确定为什么。

Answer 1

你可以使用这个正则表达式

(?s)Notes.*?(?=\n\n)

Regex Demo

Java 代码

String line = "Some info about stuff\nNotes: THis is a note about other stuff\nSo is this\n    And this\n\nThis is something else"; 
String pattern = "(?s)Notes.*?(?=\n\n|$)";
Pattern r = Pattern.compile(pattern);
Matcher m = r.matcher(line);

if (m.find()) {
    System.out.println(m.group());
}

Ideone Demo