spring boot to render xml response

In this article, we will be seeing how to produce XML response in REST end-point developed using Spring Boot.

Spring main class, which will read the XML content and produces the content as REST end-point.

package com.simple.xml;

import java.io.BufferedReader;
import java.io.File;
import java.io.FileReader;
import java.io.IOException;
import java.io.InputStream;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;

import com.fasterxml.jackson.core.JsonParseException;
import com.fasterxml.jackson.databind.JsonMappingException;
import com.fasterxml.jackson.databind.SerializationFeature;
import com.fasterxml.jackson.dataformat.xml.JacksonXmlModule;
import com.fasterxml.jackson.dataformat.xml.XmlMapper;

@SpringBootApplication
public class SpringBootApp {
    public static void main(String[] args) {

        SpringApplication.run(SpringBootApp.class, args);

    }
}

@RestController
class XmlStringConverter {

    @GetMapping(path= "/content", produces =  { "application/xml", "text/xml" })
    public String articleInfo() throws  IOException {

         // provide the path where the xml file content is present
         File xmlFile = new File("/path/of/xml/file/resources/my-articles.xml");

         String xml2String ="";
         try (BufferedReader bufReader = new BufferedReader(new FileReader(xmlFile))){ 
           StringBuilder sb = new StringBuilder(); 
           String line = bufReader.readLine(); 
           while( line != null){ sb.append(line).append("\n"); 
           line = bufReader.readLine(); } 
           xml2String= sb.toString(); 
         }
         return xml2String;
    }
}

Below is the content (file name my-articles.xml), this will read and displayed in the end-point.

Note: If the xml file is within the class path, simply use the file name when reading in java.

<note>
<to>X</to>
<from>Y</from>
<heading>Reminder</heading>
<body>Message to X from Y!</body>
</note>

Dependencies included in the pom.xml, to read xml, jackson-dataformat-xml

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
  <modelVersion>4.0.0</modelVersion>
  <groupId>rest-xml</groupId>
  <artifactId>simple-xml</artifactId>
  <version>0.0.1-SNAPSHOT</version>

   <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.2.5.RELEASE</version>
    </parent>
    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <!-- xml dependency-->
        <dependency>
            <groupId>com.fasterxml.jackson.dataformat</groupId>
            <artifactId>jackson-dataformat-xml</artifactId>
        </dependency>
        <!-- xml dependency end-->
    </dependencies>
    <properties>
        <java.version>1.8</java.version>
    </properties>
</project>

After executing the spring boot application, https://localhost:8080/content the xml content will be rendered as below.

Spring boot REST API to produce xml reading from file