正则表达式

https://www.bilibili.com/video/BV1Eq4y1E79W

元字符大全：

https://www.runoob.com/regexp/regexp-metachar.html

可视化工具：

https://c.runoob.com/front-end/7625

简单使用的示例：

import java.util.regex.Pattern;

public class Hello {
    public static void main(String[] args) {

        String content = "I am hsp from hspedu.com.";
        String pattern = ".*hspedu.*";
        boolean isMatch = Pattern.matches(pattern, content);
        System.out.println("是否整体匹配成功：" + isMatch);

    }
}