代码

package com.ruoyi.web.core.config;

import java.util.regex.Matcher;
import java.util.regex.Pattern;

public class RegexMacthTest {


    public static void main(String[] args) {
        String str = "jdbc:mysql://103.152.170.200:3306/pet?useUnicode=true&characterEncoding=utf8&zeroDateTimeBehavior=convertToNull&useSSL=true&serverTimezone=GMT%2B8";

        Pattern pattern = Pattern.compile("(?<=(?<=\\d)(\\/)).*?(?=\\?)");//编译对象
        //?<=不包含左边值     ?=不包含右边值    这需要运用零宽断言
        Matcher matcher = pattern.matcher(str);//进行匹配
        while (matcher.find()) {
            System.out.println(matcher.group());//默认是group(0)
        }
    }


}

结果

pet
Process finished with exit code 0

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