How can I change an algorithm returning a String type to return a List type in Spring?-CodePudding

The job of this snippet is: When I give a long unique url in the form of List, it converts it to a short url.

@Slf4j
@Service
public class ShortUrlService {
        private static final String SERVICE_URL = "http://mysite.co/example-api.php";
        private static final String SIGNATURE = "45abc12345";
        private static final String ACTION = "shorturl";
        private static final String FORMAT = "simple";
        private static final String SERVICE_CALL_FAIL = "SERVICE_CALL_FAIL";
        
        private Random random = new Random();
        
        @Autowired
        private HttpClient httpClient;
    
        public String shortenUrl(String url, String pCache) {
            String shortUrl = null;
            String longUrl = url;
            
            if (!StringUtils.isEmpty(pCache)) {
                longUrl = addCacheParameter(url, pCache);
            }
            
            longUrl = longUrl.replace("&", "&");
            
            try {
                shortUrl = httpClient.getRequest(buildServiceUrl(longUrl));
            } catch (IOException e) {
                log.error("Service call failed: "   e.getMessage());
                shortUrl = SERVICE_CALL_FAIL;
            }
            
            log.info("Short URL: "   shortUrl);
            
            if (shortUrl.contains("-")) {
                int rand = random.nextInt(999999);
                return shortenUrl(url, String.valueOf(rand));
            }
            
            return shortUrl;
        }
        
        private String addCacheParameter(String url, String pCache) {
            if (url.contains("?")) {
                return url   "&pCache="   pCache;
            } else {
                return url   "?pCache="   pCache;
            }
        }
    
        private String buildServiceUrl(String url) {
            StringBuilder sb = new StringBuilder();
    
            sb.append(SERVICE_URL);
            sb.append("?signature=");
            sb.append(SIGNATURE);
            sb.append("&action=");
            sb.append(ACTION);
            sb.append("&url=");
            sb.append(url);
            sb.append("&format=");
            sb.append(FORMAT);
            
            log.info("Built URL: "   sb.toString());
            
            return sb.toString();
        }
        
}

I have a service like below. The return value of this service is List I want to change to . I'm having problems in several places here can you help me fix the code?

@Slf4j
@Service
public class ShortUrlService {
      private static final String SERVICE_URL = "http://mysite.co/example-api.php";
      private static final String SIGNATURE = "45abc12345";
      private static final String ACTION = "shorturl";
      private static final String FORMAT = "simple";
      private static final String SERVICE_CALL_FAIL = "SERVICE_CALL_FAIL";
                
      private Random random = new Random();
            
      @Override
      public List<String> shortenUrl(List<String> url, String pCache) {
          List<String> shortUrl = null;
          List<String> longUrl = url;
    
          if (!StringUtils.isEmpty(pCache)) {
              longUrl = Collections.singletonList(addCacheParameter(url, pCache));
          }
    
          **longUrl = longUrl.replace("&", "&");**
    
    
          RestTemplate restTemplate = new RestTemplate();
    
            try {
                **shortUrl = restTemplate.getForObject(buildServiceUrl(longUrl),List.class);**
            } catch (Exception e) {
                log.error("Service call failed: "   e.getMessage());
                 **shortUrl =  SERVICE_CALL_FAIL;**
            }
    
            log.info("Short URL: "   shortUrl);
    
            if (shortUrl.contains("-")) {
                int rand = random.nextInt(999999);
                return shortenUrl(url, String.valueOf(rand));
            }
    
            return shortUrl;
        }
    
        private String addCacheParameter(List<String> url, String pCache) {
            if (url.contains("?")) {
                return url   "&pCache="   pCache;
            } else {
                return url   "?pCache="   pCache;
            }
        }
    
        private String buildServiceUrl(List<String> url) {
            StringBuilder sb = new StringBuilder();
    
            sb.append(SERVICE_URL);
            sb.append("?signature=");
            sb.append(SIGNATURE);
            sb.append("&action=");
            sb.append(ACTION);
            sb.append("&url=");
            sb.append(url);
            sb.append("&format=");
            sb.append(FORMAT);
    
            log.info("Built URL: "   sb.toString());
    
            return sb.toString();
        }
                
}

Here httpClient.getRequest throws an error as it remains an old technology. I wanted to use RestTemplate instead. But did I use it right? And how can i write replace method as replaceAll ?

CodePudding user response：

Use a for loop, shorten each URL in the List, and add them to another List to return.

List<String> shortUrls = new ArrayList<>(urls.size());
if (!StringUtils.isEmpty(pCache)) {
  longUrl = Collections.singletonList(addCacheParameter(url, pCache));
}
RestTemplate restTemplate = new RestTemplate();
for (String url: urls) {
    String longUrl = url.replace("&", "&");
    String shortUrl = null;
    try {
        shortUrl = restTemplate.getForObject(buildServiceUrl(longUrl),List.class);
    } catch (Exception e) {
        log.error("Service call failed: "   e.getMessage());
         shortUrl = SERVICE_CALL_FAIL;
    }
    log.info("Short URL: "   shortUrl);
    if (shortUrl.contains("-")) {
        int rand = random.nextInt(999999);
        shortUrl = shortenUrl(url, String.valueOf(rand));
    }
    shortUrls.add(shortUrl);
}
return shortUrls;

CodePudding user response：

@Slf4j
@Service
public class ShortUrlService {
      private static final String SERVICE_URL = "http://mysite.co/example-api.php";
      private static final String SIGNATURE = "45abc12345";
      private static final String ACTION = "shorturl";
      private static final String FORMAT = "simple";
      private static final String SERVICE_CALL_FAIL = "SERVICE_CALL_FAIL";
                
      private Random random = new Random();
            
      @Override
      public List<String> shortenUrl(List<String> urls, String pCache, List<String> shortUrls, List<String> longUrls) {
          
          for(String url:urls){            
          if (!StringUtils.isEmpty(pCache)) {
              longUrl = Collections.singletonList(addCacheParameter(url, pCache));
              longUrl = longUrl.replace("&", "&");
              longUrls.add(longUrl);
          }
          RestTemplate restTemplate = new RestTemplate();    
            try {
                **shortUrl = restTemplate.getForObject(buildServiceUrl(longUrl));**
            } catch (Exception e) {
                log.error("Service call failed: "   e.getMessage());
                 **shortUrl =  SERVICE_CALL_FAIL;**
            }
    
            log.info("Short URL: "   shortUrl);
    
            if (shortUrl.contains("-")) {
                int rand = random.nextInt(999999);
                return shortenUrl(url, String.valueOf(rand));
            }
            shortUrls.add(shortUrl);
            
           }
            return shortUrls;
        }
    
        private String addCacheParameter(String url, String pCache) {
            if (url.contains("?")) {
                return url   "&pCache="   pCache;
            } else {
                return url   "?pCache="   pCache;
            }
        }
    
         private String buildServiceUrl(String url) {
            StringBuilder sb = new StringBuilder();
    
            sb.append(SERVICE_URL);
            sb.append("?signature=");
            sb.append(SIGNATURE);
            sb.append("&action=");
            sb.append(ACTION);
            sb.append("&url=");
            sb.append(url);
            sb.append("&format=");
            sb.append(FORMAT);
            
            log.info("Built URL: "   sb.toString());
            
            return sb.toString();
        }
                
}

Try this.Modified some part.