Merge pull request #410 from yuriikostyshyn/YKostyshyn_spring_mvc_1

Sending media in response body using Spring MVC

spring-mvc-java/src/main/java/com/baeldung/spring/web/config/WebConfig.java

@@ -1,9 +1,15 @@
 package com.baeldung.spring.web.config;
 
+import java.util.ArrayList;
+import java.util.List;
+
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.ComponentScan;
 import org.springframework.context.annotation.Configuration;
 import org.springframework.core.io.ClassPathResource;
+import org.springframework.http.MediaType;
+import org.springframework.http.converter.ByteArrayHttpMessageConverter;
+import org.springframework.http.converter.HttpMessageConverter;
 import org.springframework.web.multipart.commons.CommonsMultipartResolver;
 import org.springframework.web.servlet.ViewResolver;
 import org.springframework.web.servlet.config.annotation.EnableWebMvc;
@@ -69,4 +75,25 @@ public class WebConfig extends WebMvcConfigurerAdapter {
         return bean;
     }
 
+    @Override
+    public void extendMessageConverters(final List<HttpMessageConverter<?>> converters) {
+        converters.add(byteArrayHttpMessageConverter());
+    }
+
+    @Bean
+    public ByteArrayHttpMessageConverter byteArrayHttpMessageConverter() {
+        final ByteArrayHttpMessageConverter arrayHttpMessageConverter = new ByteArrayHttpMessageConverter();
+        arrayHttpMessageConverter.setSupportedMediaTypes(getSupportedMediaTypes());
+
+        return arrayHttpMessageConverter;
+    }
+
+    private List<MediaType> getSupportedMediaTypes() {
+        final List<MediaType> list = new ArrayList<MediaType>();
+        list.add(MediaType.IMAGE_JPEG);
+        list.add(MediaType.IMAGE_PNG);
+        list.add(MediaType.APPLICATION_OCTET_STREAM);
+
+        return list;
+    }
 }

spring-mvc-java/src/main/java/com/baeldung/web/controller/ImageController.java

@@ -0,0 +1,27 @@
+package com.baeldung.web.controller;
+
+import java.io.IOException;
+import java.io.InputStream;
+
+import javax.servlet.ServletContext;
+
+import org.apache.commons.io.IOUtils;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.http.MediaType;
+import org.springframework.stereotype.Controller;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RequestMethod;
+import org.springframework.web.bind.annotation.ResponseBody;
+
+@Controller
+public class ImageController {
+
+    @Autowired
+    ServletContext servletContext;
+
+    @RequestMapping(value = "/image-byte-array", method = RequestMethod.GET, produces = MediaType.IMAGE_JPEG_VALUE)
+    public @ResponseBody byte[] getImageAsByteArray() throws IOException {
+        final InputStream in = servletContext.getResourceAsStream("/WEB-INF/images/image-example.jpg");
+        return IOUtils.toByteArray(in);
+    }
+}

spring-mvc-xml/pom.xml

@@ -109,7 +109,13 @@
 			<artifactId>jackson-databind</artifactId>
 			<version>2.7.2</version>
 		</dependency>
-		
+
+        <!-- IO -->
+        <dependency>
+            <groupId>commons-io</groupId>
+            <artifactId>commons-io</artifactId>
+            <version>2.2</version>
+        </dependency>
     </dependencies>
 
     <build>

spring-mvc-xml/src/main/java/com/baeldung/spring/controller/ImageController.java

@@ -0,0 +1,54 @@
+package com.baeldung.spring.controller;
+
+import java.io.IOException;
+import java.io.InputStream;
+
+import javax.servlet.ServletContext;
+
+import org.apache.commons.io.IOUtils;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.core.io.DefaultResourceLoader;
+import org.springframework.core.io.Resource;
+import org.springframework.core.io.ResourceLoader;
+import org.springframework.http.HttpHeaders;
+import org.springframework.http.HttpStatus;
+import org.springframework.http.MediaType;
+import org.springframework.http.ResponseEntity;
+import org.springframework.stereotype.Controller;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RequestMethod;
+import org.springframework.web.bind.annotation.ResponseBody;
+import org.springframework.web.context.support.ServletContextResourceLoader;
+
+@Controller
+public class ImageController {
+
+    @Autowired
+    ServletContext servletContext;
+
+    @RequestMapping(value = "/image-response-entity", method = RequestMethod.GET)
+    public ResponseEntity<byte[]> getImageAsREsponseEntity() throws IOException {
+        final InputStream in = servletContext.getResourceAsStream("/WEB-INF/images/image-example.jpg");
+        byte[] media = IOUtils.toByteArray(in);
+
+        final HttpHeaders headers = new HttpHeaders();
+        headers.setContentType(MediaType.IMAGE_JPEG);
+
+        return new ResponseEntity<byte[]>(media, headers, HttpStatus.OK);
+    }
+    
+    @RequestMapping(value = "/image-byte-array", method = RequestMethod.GET, produces = MediaType.IMAGE_JPEG_VALUE)
+    public @ResponseBody byte[] getImageAsByteArray() throws IOException {
+        final InputStream in = servletContext.getResourceAsStream("/WEB-INF/images/image-example.jpg");
+        return IOUtils.toByteArray(in);
+    }
+    
+    
+
+    @ResponseBody
+    @RequestMapping(value = "/image-resource",  method = RequestMethod.GET, produces = MediaType.IMAGE_JPEG_VALUE)
+    public Resource getImageAsResource() {
+       ResourceLoader resourceLoader = new ServletContextResourceLoader(servletContext);
+       return resourceLoader.getResource("/WEB-INF/images/image-example.jpg");
+    }
+}

spring-mvc-xml/src/main/resources/webMvcConfig.xml

@@ -5,12 +5,23 @@
         http://www.springframework.org/schema/beans 
         http://www.springframework.org/schema/beans/spring-beans-4.2.xsd
         http://www.springframework.org/schema/context
-		http://www.springframework.org/schema/context/spring-context-4.2.xsd
+        http://www.springframework.org/schema/context/spring-context-4.2.xsd
         http://www.springframework.org/schema/mvc
         http://www.springframework.org/schema/mvc/spring-mvc-4.2.xsd"
 >
 
-    <mvc:annotation-driven/>
+    <mvc:annotation-driven>
+        <mvc:message-converters>
+            <bean class="org.springframework.http.converter.ByteArrayHttpMessageConverter">
+                <property name="supportedMediaTypes">
+                    <list>
+                        <value>image/jpeg</value>
+                        <value>image/png</value>
+                    </list>
+                </property>
+            </bean>
+        </mvc:message-converters>
+    </mvc:annotation-driven>
     
     <context:component-scan base-package="com.baeldung.spring.controller"/>
     
@@ -21,8 +32,7 @@
 
     <mvc:view-controller path="/sample.html" view-name="sample"/>
 
-	<bean class="org.springframework.context.support.ResourceBundleMessageSource" id="messageSource">
-		<property name="basename" value="messages" />
-	</bean>
-
+    <bean class="org.springframework.context.support.ResourceBundleMessageSource" id="messageSource">
+        <property name="basename" value="messages" />
+    </bean>
 </beans>