首先，spring檔案下載的程式碼如下：

    /**
     * 檔案下載
     * @return
     * @throws IOException
     */
    @RequestMapping(value="/download")
    public ResponseEntity<byte[]> download(String filename)throws Exception {
        // 獲取下載檔案路徑
        String path = request.getServletContext().getRealPath("/uploads/");
        // 獲取下載檔案
        File file = new File(path + File.separator + filename);

        // 解決檔案下載時中文檔名亂碼
        String downloadFielName = new String(filename.getBytes("UTF-8"),"iso-8859-1");

        // 設定頭資訊
        HttpHeaders headers = new HttpHeaders();
        // 設定瀏覽器以attachment（下載方式）
        headers.setContentDispositionFormData("attachment", downloadFielName);
        // application/octet-stream ： 二進位制流資料
        headers.setContentType(MediaType.APPLICATION_OCTET_STREAM);
        
        return new ResponseEntity<byte[]>(FileUtils.readFileToByteArray(file), headers, HttpStatus.CREATED);
    }
 

下載下來的檔案會出現亂碼或者檔案內容損壞的情況，解決辦法如下：

在springmvc配置檔案中，配置ByteArrayHttpMessageConverter類：

<bean id="arrayHttpMessageConverter" class="org.springframework.http.converter.ByteArrayHttpMessageConverter"/>

引入該類時，該類要在StringHttpMessageConverter類和MappingJackson2HttpMessageConverter類之前；

完整配置為：

<?xml version="1.0" encoding="UTF-8"?>
<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">

    <!-- 開啟控制反轉註解的支援 -->
    <context:component-scan base-package="com.soft863" use-default-filters="false">
        <context:include-filter type="annotation" expression="org.springframework.stereotype.Controller"/>
    </context:component-scan>

    <!-- 開啟mvc註解的支援 -->
    <mvc:annotation-driven>
        <mvc:message-converters>
            <!-- arrayHttpMessageConverter要放在後面兩個之前 -->
            <ref bean="arrayHttpMessageConverter" />
            <ref bean="stringHttpMessageConverter" />
            <ref bean="mappingJackson2HttpMessageConverter" />
        </mvc:message-converters>
    </mvc:annotation-driven>

    <!-- 配置Spring檢視解析器 -->
    <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
        <property name="prefix" value="/WEB-INF/pages/"></property>
        <property name="suffix" value=".jsp"></property>
    </bean>

    <!-- 檔案上傳解析器 -->
    <bean id="multipartResolver" class="org.springframework.web.multipart.commons.CommonsMultipartResolver">
        <property name="defaultEncoding" value="utf-8"></property>
        <property name="maxUploadSize" value="999999999"></property>
    </bean>

    <!-- spring檔案下載 -->
    <bean id="arrayHttpMessageConverter" class="org.springframework.http.converter.ByteArrayHttpMessageConverter"/>

    <!-- 解決中文亂碼：該類解決當返回的資料是字串包含中文時出現亂碼問題 -->
    <bean id="stringHttpMessageConverter"
          class="org.springframework.http.converter.StringHttpMessageConverter">
        <property name="supportedMediaTypes">
            <list>
                <value>text/html;charset=utf-8</value>
            </list>
        </property>
    </bean>
    <!-- 解決IE低版本下載返回json資料 -->
    <bean id="mappingJackson2HttpMessageConverter"
          class="org.springframework.http.converter.json.MappingJackson2HttpMessageConverter">
        <property name="supportedMediaTypes">
            <list>
                <value>text/html;charset=utf-8</value>
                <value>application/json;charset=utf-8</value>
            </list>
        </property>
    </bean>

    <!-- 解決靜態資源攔截問題 -->
    <mvc:default-servlet-handler />
</beans>