REpresentational State Transfer (REST) is an architectural style that defines a set of constraints to be used for creating web services. REST API is a way of accessing web services in a simple and flexible way without having any processing. Spring MVC is a Web MVC Framework for building web applications. It is a spring module same as spring boot, spring-security, etc. The term MVC stands for Model-View-Controller architecture. REST API calls are widely used nowadays to get various information like Weather, Zip code, Cryptocurrency, University details, etc., In this article, let us try to get the Television serial details via
http://api.tvmaze.com/search/shows?q=<any TV Serial Name>
Example:
https://api.tvmaze.com/search/shows?q=mahabharata
JSON output:
[
{
"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": "<p>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.</p>",
"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": "<p><b>Mahabharat</b> 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.</p>",
"updated": 1573325769,
"_links": {
"self": {
"href": "https://api.tvmaze.com/shows/16607"
},
"previousepisode": {
"href": "https://api.tvmaze.com/episodes/762035"
}
}
}
}
]
Using Spring Framework, let us try to extract the REST API and render it on the pages.
Step by Step Implementation
Project structure:
pom.xml:
XML
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 <modelVersion>4.0.0</modelVersion> <groupId>com.TVShow.TVShow_Rest_API</groupId> <artifactId>TVShow_Rest_API</artifactId> <packaging>war</packaging> <version>0.0.1-SNAPSHOT</version> <name>TVShow</name> <properties> <failOnMissingWebXml>false</failOnMissingWebXml> <spring-version>5.1.0.RELEASE</spring-version> </properties> <dependencies> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-webmvc</artifactId> <version>${spring-version}</version> </dependency> <!-- Required for spring-test --> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-test</artifactId> <version>${spring-version}</version> </dependency> <!-- JSTL Dependency --> <dependency> <groupId>javax.servlet.jsp.jstl</groupId> <artifactId>javax.servlet.jsp.jstl-api</artifactId> <version>1.2.1</version> </dependency> <dependency> <groupId>taglibs</groupId> <artifactId>standard</artifactId> <version>1.1.2</version> </dependency> <!-- Servlet Dependency --> <dependency> <groupId>javax.servlet</groupId> <artifactId>javax.servlet-api</artifactId> <version>3.1.0</version> <scope>provided</scope> </dependency> <!-- JSP Dependency --> <dependency> <groupId>javax.servlet.jsp</groupId> <artifactId>javax.servlet.jsp-api</artifactId> <version>2.3.1</version> <scope>provided</scope> </dependency> <!-- As REST API is extracted, this is required --> <dependency> <groupId>com.google.code.gson</groupId> <artifactId>gson</artifactId> <version>2.8.6</version> </dependency> <dependency> <groupId>commons-io</groupId> <artifactId>commons-io</artifactId> <version>2.5</version> </dependency> <dependency> <groupId>junit</groupId> <artifactId>junit</artifactId> <version>4.12</version> <scope>test</scope> </dependency> </dependencies> <build> <finalName>TVShow</finalName> <sourceDirectory>src/main/java</sourceDirectory> <plugins> <plugin> <artifactId>maven-compiler-plugin</artifactId> <version>3.5.1</version> <configuration> <source>1.8</source> <target>1.8</target> </configuration> </plugin> <plugin> <groupId>org.apache.maven.plugins</groupId> <artifactId>maven-war-plugin</artifactId> <version>3.3.2</version></plugin> <plugin> <groupId>org.codehaus.mojo</groupId> <artifactId>tomcat-maven-plugin</artifactId> <version>1.0-beta-1</version> </plugin> </plugins> </build></project> |
index.jsp:
This is the page that gets rendered when the project is deployed in tomcat
Java
<!DOCTYPE html><html lang="en"><head> <meta charset="utf-8"> <meta http-equiv="X-UA-Compatible" content="IE=edge"> <meta name="viewport" content="width=device-width, initial-scale=1"> <title>TVShow</title> <link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/4.5.0/css/bootstrap.min.css"> // for making the page styles are applied <style type="text/css"> .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; } </style></head><body><div class="main-form" id="main-form"> <section> <div class="form-group"> // We need to input the search string in this box <input id="searchStr" type="text" class="form-control" placeholder="Enter TVShow name here..." required="required"> </div> <div class="form-group"> <button onclick="loadData()" class="btn btn-primary btn-block">Find TVShow Details</button> </div> </section></div><div class="profile-area hideElement" id="profile-area"> <section> <div id="loader" class="hideElement"> <div class="spinner-border" role="status"> <span class="sr-only">Loading...</span> </div> </div> <div id="profile" class="hideElement"> <br><br> // parsed json object details are displayed here <p><strong>TVShowScore : </strong><span id="scores"></span></p> <p><strong>TVShow URL : </strong><span id="url"></span></p> <p><strong>IMDB : </strong><span id="imdb"></span></p> </div> </section></div></body><script> 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...") } }</script></html> |
Output:
On entering any TVShow name in the input box, we will get the below details.
Execution Process:
From the JSP page, a “GET” method is invoked with the search string and it is redirected to the Spring Controller class, where the REST API URL, http://api.tvmaze.com/search/shows?q=<searchString> is invoked and it will create the JSON Array as given above, From that, we are taking
"score", "url" and "imdb" values alone Example: "score": 0.42338097, "url": "https://www.tvmaze.com/shows/16607/mahabharat", "imdb": "tt0158417"
Actually, on this page, we have retrieved only TVShowScore, TVShow URL, and IMDB alone. But we can get all other details that are available in JSON. Required code for retrieving the data and parsing the JSON output is as follows. Important necessary files to achieve the flow
AppConfig.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[] { "/" }; } } |
TVShowController.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; @Controllerpublic 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<JsonElement> 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=<searchstring> // is the url to access the TV show details 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; }} |
Conclusion
By using Spring-webmvc, we can able to get the details from REST API calls. The above is an excellent example of it. Similarly, there are so many open-source REST API calls are available. That means we can retrieve the data by using them. Few examples of open source REST API calls.
|
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 |
