This is example of download file using streaming with spring framework. So many time user want to download large file at that time instead of direct download file it better option to provide steaming. In steaming server is writing file and client is downloading file parallel, server send file in chunk.

Technology Used:

  1. String 4.3.0
  2. Maven 2.3.2
  3. Tomcat 7
  4. Java 8
  5. IntelljIDEA 14

Project structure

Dependency:

pom.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 http://maven.apache.org/maven-v4_0_0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <groupId>com.springapp</groupId>
    <artifactId>spring-download-file</artifactId>
    <packaging>war</packaging>
    <version>1.0-SNAPSHOT</version>
    <name>spring-download-file</name>

    <properties>
        <spring.version>4.3.0.RELEASE</spring.version>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-core</artifactId>
            <version>${spring.version}</version>
        </dependency>

        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-web</artifactId>
            <version>${spring.version}</version>
        </dependency>

        <dependency>
            <groupId>javax.servlet</groupId>
            <artifactId>servlet-api</artifactId>
            <version>2.5</version>
        </dependency>

        <dependency>
            <groupId>javax.servlet.jsp</groupId>
            <artifactId>jsp-api</artifactId>
            <version>2.1</version>
            <scope>provided</scope>
        </dependency>

        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-webmvc</artifactId>
            <version>${spring.version}</version>
        </dependency>

        <!-- https://mvnrepository.com/artifact/org.apache.commons/commons-io -->
        <dependency>
            <groupId>org.apache.commons</groupId>
            <artifactId>commons-io</artifactId>
            <version>1.3.2</version>
        </dependency>

        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-test</artifactId>
            <version>${spring.version}</version>
            <scope>test</scope>
        </dependency>

        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.11</version>
            <scope>test</scope>
        </dependency>
    </dependencies>

    <build>
        <finalName>spring-hello-work</finalName>
        <plugins>
            <plugin>
                <artifactId>maven-compiler-plugin</artifactId>
                <configuration>
                    <source>1.8</source>
                    <target>1.8</target>
                </configuration>
            </plugin>
            <plugin>
                <artifactId>maven-surefire-plugin</artifactId>
                <configuration>
                    <includes>
                        <include>**/*Tests.java</include>
                    </includes>
                </configuration>
            </plugin>
        </plugins>
    </build>
</project>

Java Code:

HelloController.java

package com.springdemo;

import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.servlet.mvc.method.annotation.StreamingResponseBody;
import javax.servlet.http.HttpServletResponse;
import java.io.*;

@Controller
@RequestMapping("/")
public class HelloController {

    @RequestMapping(value = "getSteamingFile", method = RequestMethod.GET)
    public StreamingResponseBody getSteamingFile(HttpServletResponse response) throws IOException{
        response.setContentType("application/pdf");
        response.setHeader("Content-Disposition", "attachment; filename=\"demo-file.pdf\"");
        return new StreamingResponseBody() {
            @Override
            public void writeTo(OutputStream outputStream) throws IOException {
                // write...
                InputStream inputStream=new FileInputStream(new File("C:\\demo-file.pdf"));
                    try {
                        org.apache.commons.io.IOUtils.copy(inputStream,outputStream);
                    }catch (Exception e){

                    }
                }
        };
    }
}

pages/hello.jsp

<html>
<body>
  <h1>Your request submitted successfully. Request running in back ground.</h1>
</body>
</html>

Configurations:

mvc-dispatcher-servlet.xml

<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:context="http://www.springframework.org/schema/context"
       xmlns:mvc="http://www.springframework.org/schema/mvc"
       xsi:schemaLocation="http://www.springframework.org/schema/beans
        http://www.springframework.org/schema/beans/spring-beans.xsd
        http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd
        http://www.springframework.org/schema/mvc
         http://www.springframework.org/schema/mvc/spring-mvc.xsd">

    <context:component-scan base-package="com.springdemo"/>

    <mvc:annotation-driven>
        <mvc:async-support default-timeout="30000" task-executor="taskExecutor"/>
    </mvc:annotation-driven>

    <bean id="taskExecutor" class="org.springframework.scheduling.concurrent.ThreadPoolTaskExecutor">
        <property name="corePoolSize" value="5"/>
        <property name="maxPoolSize" value="50"/>
        <property name="queueCapacity" value="10"/>
        <property name="keepAliveSeconds" value="120"/>
    </bean>

    <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
        <property name="prefix" value="/WEB-INF/pages/"/>
        <property name="suffix" value=".jsp"/>
    </bean>

</beans>

web.xml

<web-app xmlns="http://java.sun.com/xml/ns/javaee"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="
            http://java.sun.com/xml/ns/javaee
            http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd"
         version="3.0">


<display-name>Spring MVC Application</display-name>

    <servlet>
    <servlet-name>mvc-dispatcher</servlet-name>
    <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
        <load-on-startup>1</load-on-startup>
        <async-supported>true</async-supported>
  </servlet>

  <servlet-mapping>
    <servlet-name>mvc-dispatcher</servlet-name>
    <url-pattern>/</url-pattern>

  </servlet-mapping>



</web-app>

AppTests.java

package com.springdemo;

import org.junit.Before;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.test.context.ContextConfiguration;
import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
import org.springframework.test.context.web.WebAppConfiguration;
import org.springframework.test.web.servlet.MockMvc;
import org.springframework.web.context.WebApplicationContext;

import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.get;
import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;
import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.view;
import static org.springframework.test.web.servlet.setup.MockMvcBuilders.webAppContextSetup;

@RunWith(SpringJUnit4ClassRunner.class)
@WebAppConfiguration
@ContextConfiguration("file:src/main/webapp/WEB-INF/mvc-dispatcher-servlet.xml")
public class AppTests {
    private MockMvc mockMvc;

    @SuppressWarnings("SpringJavaAutowiringInspection")
    @Autowired
    protected WebApplicationContext wac;

    @Before
    public void setup() {
        this.mockMvc = webAppContextSetup(this.wac).build();
    }

    @Test
    public void simple() throws Exception {
        mockMvc.perform(get("/"))
                .andExpect(status().isOk())
                .andExpect(view().name("hello"));
    }
}

Output:

spring-streaming-body-download-file

spring-streaming-body-download-file

 

donwload-chunked

donwload-chunked

Download source code

spring-download-file

Was this post helpful?
Let us know, if you liked the post. Only in this way, we can improve us.
Yes
No

Leave a Reply

Your email address will not be published. Required fields are marked *