拆分java中的字符串而不删除匹配项

Question

我尝试在不删除匹配字符串的情况下拆分字符串，我取得了一定的成功，因为我发现可以使用(?<=-)|(?=-)，但现在如果我实现它来提取链接，使用下面的regex表达式：

((?<=(http:\\/\\/\\S+))|(?=(http:\\/\\/\\S+)))我收到了一个奇怪的警告。实际上，拆分以下输入：

A wonderful serenity has taken possession of http://www.google.com my entire soul,\n like these sweet mornings of spring which I enjoy with my whole heart.

给出了这组字符串：

["A wonderful serenity has taken possession of ", "http://w", "w", "w", ".", "g", "o", "o", "g", "g", "l", "e", ".", "c", "o", "m", "my entire soul,\n like these sweet mornings of spring which I enjoy with my whole heart."]

..。

编辑:成功的输出应该是：

["A wonderful serenity has taken possession of ", "http://www.google.com", "my entire soul,\n like these sweet mornings of spring which I enjoy with my whole heart."]

Answer 1

这里一个可行的选择是使用正式的正则表达式迭代器，并搜索以下模式：

\\bhttps?://\\S+\\b|.*?(?=https?://|$)

此模式将首先尝试寻找URL，否则它将捕获所有向上的内容，但包括下一个URL或输入的末尾。以下是示例代码：

String input = "A wonderful serenity has taken possession of http://www.google.com my entire soul,\n like these sweet mornings of spring which I enjoy with my whole heart.";
String pattern = "\\bhttps?://\\S+\\b|.*?(?=https?://|$)";
Pattern r = Pattern.compile(pattern);
Matcher m = r.matcher(input);
List matches = new ArrayList<>();
while (m.find()) {
    matches.add(m.group());
}
System.out.println(matches);

这将打印：

[A wonderful serenity has taken possession of ,
 http://www.google.com,
 like these sweet mornings of spring which I enjoy with my whole heart., ]