如何通过 REST API 和 Spring MVC 提取电视节目详细信息？

REpresentational State Transfer (REST)是一种架构风格，它定义了一组用于创建 Web 服务的约束。 REST API 是一种无需任何处理即可以简单灵活的方式访问 Web 服务的方式。 Spring MVC 是一个用于构建 Web 应用程序的 Web MVC 框架。它是一个与 spring boot、spring-security 等相同的 spring 模块。术语 MVC 代表 Model-View-Controller 架构。 REST API 调用现在广泛用于获取各种信息，例如天气、邮政编码、加密货币、大学详细信息等，在本文中，让我们尝试通过以下方式获取电视连续剧详细信息

http://api.tvmaze.com/search/shows?q=

例子：

https://api.tvmaze.com/search/shows?q=mahabharata

JSON输出：

[
  {
    "score": 0.6494496,
    "show": {
      "id": 60856,
      "url": "https://www.tvmaze.com/shows/60856/the-mahabharata",
      "name": "The Mahabharata",
      "type": "Scripted",
      "language": "English",
      "genres": [],
      "status": "Ended",
      "runtime": null,
      "averageRuntime": null,
      "premiered": "1990-03-10",
      "ended": "1990-03-24",
      "officialSite": null,
      "schedule": {
        "time": "",
        "days": []
      },
      "rating": {
        "average": null
      },
      "weight": 0,
      "network": {
        "id": 269,
        "name": "Star Plus",
        "country": {
          "name": "India",
          "code": "IN",
          "timezone": "Asia/Kolkata"
        },
        "officialSite": null
      },
      "webChannel": null,
      "dvdCountry": null,
      "externals": {
        "tvrage": null,
        "thetvdb": 213551,
        "imdb": "tt0097810"
      },
      "image": {
        "medium": "https://static.tvmaze.com/uploads/images/medium_portrait/398/996547.jpg",
        "original": "https://static.tvmaze.com/uploads/images/original_untouched/398/996547.jpg"
      },
      "summary": null,
      "updated": 1646508699,
      "_links": {
        "self": {
          "href": "https://api.tvmaze.com/shows/60856"
        },
        "previousepisode": {
          "href": "https://api.tvmaze.com/episodes/2289706"
        }
      }
    }
  },
  {
    "score": 0.5061876,
    "show": {
      "id": 5016,
      "url": "https://www.tvmaze.com/shows/5016/mahabharat",
      "name": "Mahabharat",
      "type": "Scripted",
      "language": "Hindi",
      "genres": [
        "Drama",
        "History"
      ],
      "status": "Ended",
      "runtime": 20,
      "averageRuntime": 20,
      "premiered": "2013-09-16",
      "ended": "2014-08-16",
      "officialSite": "http://www.hotstar.com/#!/mahabharat-435-s",
      "schedule": {
        "time": "20:30",
        "days": [
          "Monday",
          "Tuesday",
          "Wednesday",
          "Thursday",
          "Friday",
          "Saturday",
          "Sunday"
        ]
      },
      "rating": {
        "average": null
      },
      "weight": 47,
      "network": {
        "id": 269,
        "name": "Star Plus",
        "country": {
          "name": "India",
          "code": "IN",
          "timezone": "Asia/Kolkata"
        }
      },
      "webChannel": null,
      "dvdCountry": null,
      "externals": {
        "tvrage": 46350,
        "thetvdb": 273350,
        "imdb": "tt3212600"
      },
      "image": {
        "medium": "https://static.tvmaze.com/uploads/images/medium_portrait/21/54241.jpg",
        "original": "https://static.tvmaze.com/uploads/images/original_untouched/21/54241.jpg"
      },
      "summary": "
The story of the throne of Hastinapura, the kingdom ruled by the Kuru clan. The two collateral branches of the family that participate in the struggle of the throne of Hastinapura are the Kaurava and the Pandava. Although the Kaurava is the senior branch of the family, Duryodhana, the eldest Kaurava, is younger than Yudhisthira, the eldest Pandava. Both Duryodhana and Yudhisthira claim to be first in line to inherit the throne. The struggle culminates in the great battle of Kurukshetra, in which the Pandavas are ultimately victorious. The battle produces complex conflicts of kinship and friendship, instances of family loyalty and duty taking precedence over what is right, as well as the converse.
",
      "updated": 1604823863,
      "_links": {
        "self": {
          "href": "https://api.tvmaze.com/shows/5016"
        },
        "previousepisode": {
          "href": "https://api.tvmaze.com/episodes/314287"
        }
      }
    }
  },
  {
    "score": 0.42338097,
    "show": {
      "id": 16607,
      "url": "https://www.tvmaze.com/shows/16607/mahabharat",
      "name": "Mahabharat",
      "type": "Scripted",
      "language": "Hindi",
      "genres": [
        "Drama"
      ],
      "status": "Ended",
      "runtime": 45,
      "averageRuntime": 45,
      "premiered": "1988-10-02",
      "ended": "1990-07-15",
      "officialSite": null,
      "schedule": {
        "time": "",
        "days": [
          "Sunday"
        ]
      },
      "rating": {
        "average": null
      },
      "weight": 17,
      "network": {
        "id": 1093,
        "name": "DD National",
        "country": {
          "name": "India",
          "code": "IN",
          "timezone": "Asia/Kolkata"
        }
      },
      "webChannel": null,
      "dvdCountry": null,
      "externals": {
        "tvrage": null,
        "thetvdb": 84349,
        "imdb": "tt0158417"
      },
      "image": {
        "medium": "https://static.tvmaze.com/uploads/images/medium_portrait/55/138442.jpg",
        "original": "https://static.tvmaze.com/uploads/images/original_untouched/55/138442.jpg"
      },
      "summary": "
Mahabharat is a successful Indian television series based on the ancient Indian epic Mahabharata. The 94-episode series originally ran from 1988 to 1990. It was produced by B. R. Chopra and directed by his son, Ravi Chopra.
",
      "updated": 1573325769,
      "_links": {
        "self": {
          "href": "https://api.tvmaze.com/shows/16607"
        },
        "previousepisode": {
          "href": "https://api.tvmaze.com/episodes/762035"
        }
      }
    }
  }
]

使用 Spring Framework，让我们尝试提取 REST API 并将其呈现在页面上。

分步实施

项目结构：

pom.xml：

XML

    4.0.0
    com.TVShow.TVShow_Rest_API
    TVShow_Rest_API
    war
    0.0.1-SNAPSHOT
    TVShow
    http://maven.apache.org
    
        false
        5.1.0.RELEASE
    
    
        
        
        
            org.springframework
            spring-webmvc
            ${spring-version}
        
        
        
        
            org.springframework
            spring-test
            ${spring-version}
        
  
        
        
            javax.servlet.jsp.jstl
            javax.servlet.jsp.jstl-api
            1.2.1
        
        
        
            taglibs
            standard
            1.1.2
        
  
        
        
            javax.servlet
            javax.servlet-api
            3.1.0
            provided
        
  
        
        
            javax.servlet.jsp
            javax.servlet.jsp-api
            2.3.1
            provided
        
        
          
        
            com.google.code.gson
            gson
            2.8.6
        
        
            commons-io
            commons-io
            2.5
        
        
            junit
            junit
            4.12
            test
        
    
    
        TVShow
        src/main/java
        
            
                maven-compiler-plugin
                3.5.1
                
                    1.8
                    1.8
                
            
              
            
  org.apache.maven.plugins
  maven-war-plugin
  3.3.2

  
      
        org.codehaus.mojo
        tomcat-maven-plugin
        1.0-beta-1
      
        
          
    

index.jsp：

这是项目部署在 tomcat 中时呈现的页面

Java

    
    
    
    TVShow
    
    
    
    // for making the page styles are applied 
    
        .main-form, .profile-area {
            width: 500px;
        }
        .main-form {
            margin: 50px auto 0px;
        }
        .profile-area {
            margin: 10px auto;
        }
        .main-form section, .profile-area section {
            margin-bottom: 15px;
            background: #097969;
            box-shadow: 0px 2px 2px rgba(0, 0, 0, 0.3);
            color: white;
        }
        .main-form section {
            padding: 30px;
        }
        .profile-area section {
            padding: 30px 30px 30px;
        }
        .profile-area section > div {
            text-align: center;
        }
        .main-form h3 {
            margin: 0 0 15px;
        }
        .form-control, .btn {
            min-height: 38px;
            border-radius: 2px;
        }
        .btn {
            font-size: 15px;
            font-weight: bold;
        }
        .hideElement {
            display: none;
        }
    



    
        
            // We need to input the search string in this box
            
        
        
            Find TVShow Details
        
    


    
        
            
                Loading...
            
        
        
            
            // parsed json object details are displayed here
              
TVShowScore : 
  
              
TVShow URL : 
  
              
IMDB : 
  
        
    



    function loadData() {
        document.getElementById("profile-area").classList.remove("hideElement");
        document.getElementById("loader").classList.remove("hideElement");
        document.getElementById("profile").classList.add("hideElement");
  
        var searchStr = document.getElementById("searchStr").value;
  
        if(searchStr != "" && searchStr != null ) {
            var xhttp = new XMLHttpRequest();
            xhttp.onreadystatechange = function() {
                if (this.readyState == 4 && this.status == 200) {
                    var jsonResponse = JSON.parse(this.responseText);
                    document.getElementById("scores").innerHTML = jsonResponse.scores;
                    document.getElementById("url").innerHTML = jsonResponse.url;
                    document.getElementById("imdb").innerHTML = jsonResponse.imdb;
                    document.getElementById("loader").classList.add("hideElement");
                    document.getElementById("profile").classList.remove("hideElement");
                }
            };
            // GET method which redirects the jsp to connect to
            // the servlet with the search string
            xhttp.open("GET", "getTVShowDetailsBySearchString?searchStr="+  searchStr, true);
            xhttp.send();
            console.log("done");
        } else {
            console.log("Enter search string to check...")
        }
    }

输出：

在输入框中输入任何电视节目名称后，我们将获得以下详细信息。

执行过程：

在 JSP 页面中，使用搜索字符串调用“GET”方法，并将其重定向到 Spring Controller 类，其中 REST API URL http://api.tvmaze.com/search/shows?q= 被调用，它将创建上面给出的 JSON 数组，从那里，我们正在采取

"score", "url" and "imdb" values alone

Example:
"score": 0.42338097,    
"url": "https://www.tvmaze.com/shows/16607/mahabharat",      
"imdb": "tt0158417"

实际上，在这个页面上，我们只检索了 TVShowScore、TVShow URL 和 IMDB。但是我们可以获得 JSON 中可用的所有其他详细信息。检索数据和解析 JSON 输出所需的代码如下。实现流程的重要必要文件

应用配置。Java：

Java

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.servlet.config.annotation.EnableWebMvc;
import org.springframework.web.servlet.view.InternalResourceViewResolver;
import org.springframework.web.servlet.view.JstlView;
  
@Configuration
@EnableWebMvc
@ComponentScan(basePackages = { "com.TVShow.TVShow_Rest_API" })
public class AppConfig {
  
    @Bean
    public InternalResourceViewResolver resolver() {
        InternalResourceViewResolver resolver = new InternalResourceViewResolver();
        resolver.setViewClass(JstlView.class);
        resolver.setPrefix("/");
        resolver.setSuffix(".jsp");
        return resolver;
    }
  
}

SpringMvcDispatcherServletInitializer。Java：

Java

import org.springframework.web.servlet.support.AbstractAnnotationConfigDispatcherServletInitializer;
  
public class SpringMvcDispatcherServletInitializer extends AbstractAnnotationConfigDispatcherServletInitializer {
   
    @Override
    protected Class[] getRootConfigClasses() {
        return null;
    }
   
    @Override
    protected Class[] getServletConfigClasses() {
        return new Class[] { AppConfig.class };
    }
   
    @Override
    protected String[] getServletMappings() {
        return new String[] { "/" };
    }
   
}

电视节目控制器。Java：

Java

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.URL;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.StringTokenizer;
  
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.ResponseBody;
  
import com.google.gson.Gson;
import com.google.gson.JsonArray;
import com.google.gson.JsonElement;
import com.google.gson.JsonObject;
  
@Controller
public class TVShowController {
  
    @RequestMapping("/getTVShowDetailsBySearchString")
    public @ResponseBody
    JsonObject getTVShowDetailsBySearchString(String  searchStr) throws IOException {
        // According to the search string, JSONArray
        // or JSON Object is constructed.
        // In our case, it is producing JSONArray
        JsonArray jsonArray = new JsonArray();
        jsonArray = getTVShowDetailsBySearchStr(searchStr);
        JsonObject finalJsonObject = new JsonObject();
        ArrayList scoreList = new ArrayList();
        ArrayList showUrlList = new ArrayList();
        ArrayList showUrlLinks = new ArrayList();
        ArrayList telecastedList = new ArrayList();
        ArrayList imdbList = new ArrayList();
        Iterator objectIterator =  jsonArray.iterator();
        // Iterating
        while(objectIterator.hasNext()) {
            JsonElement object = objectIterator.next();
            JsonObject jObj = object.getAsJsonObject();
            // We have to get the score and
            // replace the special characters
            scoreList.add(jObj.get("score").toString().replaceAll("^\"|\"$", ""));
            // Similarly show
            showUrlList.add(jObj.get("show").toString().replaceAll("^\"|\"$", ""));
  
        }
          
        for (int i = 0;i < showUrlList.size();i++) {          
              
            StringTokenizer jsonTokenizer = new StringTokenizer(showUrlList.get(i).toString(),","); 
            String  expectedTag = null; 
            int idx = 0; 
            while (jsonTokenizer.hasMoreTokens()) { 
                expectedTag = jsonTokenizer.nextToken();
                if (expectedTag.contains("url")) {
                    showUrlLinks.add(expectedTag.substring(7,expectedTag.length()-1).toString());
                }
                if (expectedTag.contains("timezone")) {
                    telecastedList.add(expectedTag.substring(12,expectedTag.length()-3).toString());
                }
                if (expectedTag.contains("imdb")) {
                    imdbList.add(expectedTag.substring(8,expectedTag.length()-2).toString());
                }
        }
    }
        finalJsonObject.addProperty("scores", scoreList.toString());
        finalJsonObject.addProperty("scoresize", scoreList.size());
        finalJsonObject.addProperty("url", showUrlLinks.toString());
        finalJsonObject.addProperty("urlsize", showUrlLinks.size());
        finalJsonObject.addProperty("timezone", telecastedList.toString());
        finalJsonObject.addProperty("imdb", imdbList.toString());
        finalJsonObject.addProperty("imdbsize", imdbList.size());
        // After retrieving the elements, 
        // in an object , all are constructed
        return finalJsonObject;
    }
  
    private JsonArray getTVShowDetailsBySearchStr(String searchString) throws IOException {
  
        StringBuilder responseData = new StringBuilder();
        JsonArray jsonArray = null;
  
        URL url = null;
        // http://api.tvmaze.com/search/shows?q= 
        // is the url to access the TV show details
        url = new URL("http://api.tvmaze.com/search/shows?q=" +  searchString);
          
        HttpURLConnection con = (HttpURLConnection) url.openConnection();
        con.setRequestMethod("GET");
        con.setRequestProperty("User-Agent", "Mozilla/5.0");
        int responseCode = con.getResponseCode();
  
        System.out.println("\nSending 'GET' request to URL : " + url);
        // System.out.println("Response Code : " + responseCode);
  
        try (BufferedReader in = new BufferedReader(
                new InputStreamReader(con.getInputStream()))) {
  
            String line;
  
            while ((line = in.readLine()) != null) {
                responseData.append(line);
            }
            // It is getting converted to 
            // JSONArray by means of below code
            jsonArray = new Gson().fromJson(responseData.toString(), JsonArray.class);    
        }
        return jsonArray;
    }
}

结论

通过使用 Spring-webmvc，我们可以从 REST API 调用中获取详细信息。上面就是一个很好的例子。同样，有很多可用的开源 REST API 调用。这意味着我们可以使用它们来检索数据。开源 REST API 调用的几个示例。

API Name	Description	Sample URL
CoinBase	Currency codes and Names	https://api.coinbase.com/v2/currencies
ExchangeRate-API	Exchange Rates	https://open.er-api.com/v6/latest/USD
WeatherDB	Weather Data	https://weatherdbi.herokuapp.com/data/weather/london