Java 正则表达式中是否有NOT运算符

字符串：

The car has <ex id=\"3\"/><g id=\"4\">attributes</g><g id=\"5\">, such as weight and color

使用正则表达式：

我能得到像和这样的标签

但是我们怎样才能从句子中删除所有的字符串部分，使最后的字符串看起来像这样呢

只有标签

---

Q：删除句子中的任何内容，但标记不是标记的运算符。

下面的代码使用所需的标记创建一个新字符串

public static void main(String[] args)
{
    String line = "The car has <ex id=\\\"3\\\"/><g id=\\\"4\\\">attributes</g><g id=\\\"5\\\">, such as weight and color";
    String regex = "(<.*?>)";
    Pattern pattern = Pattern.compile(regex);
    Matcher matcher = pattern.matcher(line);
    StringBuilder compactline = new StringBuilder();
    while (matcher.find()) {
        compactline.append(matcher.group());
    }
    System.out.println("Original Line : " + line);
    System.out.println("Compact Line : " + compactline);
}

输出

Original Line : The car has <ex id=\"3\"/><g id=\"4\">attributes</g><g id=\"5\">, such as weight and color

Compact Line : <ex id=\"3\"/><g id=\"4\"></g><g id=\"5\">

---

下面的代码使用所需的标记创建一个新字符串

public static void main(String[] args)
{
    String line = "The car has <ex id=\\\"3\\\"/><g id=\\\"4\\\">attributes</g><g id=\\\"5\\\">, such as weight and color";
    String regex = "(<.*?>)";
    Pattern pattern = Pattern.compile(regex);
    Matcher matcher = pattern.matcher(line);
    StringBuilder compactline = new StringBuilder();
    while (matcher.find()) {
        compactline.append(matcher.group());
    }
    System.out.println("Original Line : " + line);
    System.out.println("Compact Line : " + compactline);
}

输出

Original Line : The car has <ex id=\"3\"/><g id=\"4\">attributes</g><g id=\"5\">, such as weight and color

Compact Line : <ex id=\"3\"/><g id=\"4\"></g><g id=\"5\">

输出：

matcher =<ex id=\"3\"/>
matcher =<g id=\"4\">
matcher =</g>
matcher =<g id=\"5\">
matcher =</g>
matcher =<g id=\"6\">
matcher =</g>
matcher =<g id=\"7\">
matcher =</g>

在尝试@anubhava的建议时，此代码段起作用，只获取字符串中存在的标记

输出：

matcher =<ex id=\"3\"/>
matcher =<g id=\"4\">
matcher =</g>
matcher =<g id=\"5\">
matcher =</g>
matcher =<g id=\"6\">
matcher =</g>
matcher =<g id=\"7\">
matcher =</g>

在尝试@anubhava的建议时，此代码段起作用，仅获取字符串中存在的标记。

在Matcher.group0中使用相同的正则表达式查找并获取新字符串。使用Matcher.group0在Matcher中使用相同的正则表达式。使用Matcher.group0查找并获取新字符串