SpringBoot短链接跳转的代码实现

import lombok.AllArgsConstructor;
import lombok.Builder;
import lombok.Data;
import lombok.NoArgsConstructor;
 
import java.time.Instant;
 
@Data
@Builder
@AllArgsConstructor
@NoArgsConstructor
public class UrlMap {
 
 
    private Long id;
 
    private String longUrl;
 
    private String shortUrl;
 
    private String username;
 
    private Instant expireTime;
 
    private Instant creationTime;
 
 
 
}

        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <optional>true</optional>
        </dependency>

import com.zhan.zhan215.Entity.UrlMap;
import org.apache.ibatis.annotations.Mapper;
import org.apache.ibatis.annotations.Param;
 
import java.time.Instant;
import java.util.List;
 
 
@Mapper
public interface UrlMapMapper {
 
    UrlMap findFirstByLongUrl(@Param("longUrl") String longUrl, @Param("username") String username);
 
    void saveUrlMap(UrlMap urlMap);
 
    UrlMap findByShortUrl(String shortUrl);
 
 
}

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.zhan.zhan215.Dao.UrlMapMapper">
 
    <select id="findFirstByLongUrl" parameterType="string" resultType="com.zhan.zhan215.Entity.UrlMap">
 
        select *
 
        from t_url_map
 
        where longUrl =#{longUrl} and username = #{username}
 
        limit 1
 
    </select>
 
    <!-- 在Mapper XML文件中定义保存urlMap对象的方法 -->
    <insert id="saveUrlMap" parameterType="com.zhan.zhan215.Entity.UrlMap">
        INSERT INTO t_url_map (shortUrl, longUrl,username)
        VALUES (#{shortUrl}, #{longUrl},#{username})
    </insert>
 
    <select id="findByShortUrl"  parameterType="string" resultType="com.zhan.zhan215.Entity.UrlMap">
 
        select *
 
        from t_url_map
 
        where shortUrl = #{shortUrl} limit 1
 
    </select>

import com.zhan.zhan215.Dao.UrlMapMapper;
import com.zhan.zhan215.Entity.UrlMap;
import org.springframework.stereotype.Service;
 
import javax.annotation.Resource;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.time.Instant;
 
@Service
public class UrlMapService {
 
    @Resource
    private UrlMapMapper urlMapMapper;
 
 
    // 编码
    public String encode(String longUrl,String username) {
 
        UrlMap urlMap = urlMapMapper.findFirstByLongUrl(longUrl,username);
 
        // 看看该长链接是否存在
        // 如果存在并且其对应用户名等于已有用户名，则直接给出短链接
        if (urlMap != null&&username.equals(urlMap.getUsername())) {
            return urlMap.getShortUrl();
 
        } else {
            // 如果不存在,则生成短链接
            UrlMap urlMap1 = new UrlMap();
            // 生成短链接
            String shortLink = generateShortLink(longUrl,username);
            // 保存短链接
            urlMap1.setLongUrl(longUrl);
            urlMap1.setShortUrl(shortLink);
            urlMap1.setUsername(username);
            urlMap1.setCreationTime(Instant.now());
            urlMapMapper.saveUrlMap(urlMap1);
 
 
            return shortLink;
        }
    }
 
    // 解码
    public String decode(String shortUrl){
 
        // 根据短链接获取长链接
        UrlMap byShortUrl = urlMapMapper.findByShortUrl(shortUrl);
 
        // 如果存在，返回长链接
        if(byShortUrl!=null){
            return byShortUrl.getLongUrl();
        }
 
        // 如果没有，返回首页（正常是返回一个失败页面）
        return "https://bilibili.com";
 
    }
 
    // 生成短链接
    public static String generateShortLink(String originalUrl,String username) {
        try {
            MessageDigest md = MessageDigest.getInstance("MD5");
            byte[] hashBytes = md.digest(originalUrl.getBytes());
            // 对原始URL进行MD5哈希计算
 
            StringBuilder sb = new StringBuilder();
            for (byte b : hashBytes) {
                sb.append(String.format("%02x", b));
                // 将字节数组转换为十六进制字符串
            }
 
            return sb.toString().substring(0, 8)+username;
            // 截取前8位，加上用户名（这里先简单默认用户名是4位数）
        } catch (NoSuchAlgorithmException e) {
            e.printStackTrace();
            return null;
        }
    }
 
 
}

import com.zhan.zhan215.Common.ResponseBean;
import com.zhan.zhan215.Service.UrlMapService;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.servlet.view.RedirectView;
 
import javax.annotation.Resource;
 
@RestController
public class UrlMapController {
 
    @Resource
    private UrlMapService urlMapService;
 
 
 
    @PostMapping("/shorten")
    // 长链接转短连接,相当于实际项目中的点击“分享”，形成一条短连接
    public ResponseBean shorten(@RequestParam String longUrl,@RequestParam String username){
 
        String encode =  urlMapService.encode(longUrl,username);
        // 形成短链
 
        return ResponseBean.success(encode);
 
    }
 
    @GetMapping("redirect")
    //重定向
    public RedirectView redirectView(@RequestParam String shortUrl){
 
        String longUrl = urlMapService.decode(shortUrl);
 
        return new RedirectView(longUrl);
    }
 
}

public class ResponseBean<T> {
 
    /** 200:操作成功  -1：操作失败**/
 
    // http 状态码
    private boolean success;
 
    // 返回的数据
    private T data;
 
    public boolean isSuccess() {
        return success;
    }
 
    public void setSuccess(boolean success) {
        this.success = success;
    }
 
    public T getData() {
        return data;
    }
 
    public void setData(T data) {
        this.data = data;
    }
 
    public static <T> ResponseBean<T> success(T data) {
        ResponseBean<T> responseBean = new ResponseBean<>();
        responseBean.setSuccess(true);
        responseBean.setData(data);
        return responseBean;
    }
 
    public static <T> ResponseBean<T> error(T errorData) {
        ResponseBean<T> responseBean = new ResponseBean<>();
        responseBean.setSuccess(false);
        responseBean.setData(errorData);
        return responseBean;
    }
 
    public static <T> ResponseBean<T> success() {
        ResponseBean<T> responseBean = new ResponseBean<>();
        responseBean.setSuccess(true);
        return responseBean;
    }
 
}