FileUpload

依赖

Maven

<!-- Apache Commons FileUpload --> 
<dependency>
    <groupId>commons-fileupload</groupId>
    <artifactId>commons-fileupload</artifactId>
    <version>1.3.1</version>
</dependency>

<!-- Apache Commons IO --> 
<dependency>
    <groupId>commons-io</groupId>
    <artifactId>commons-io</artifactId>
    <version>2.4</version>
</dependency>

Spring MVC 配置

利用Apache Commons FileUpload 来处理请求，仅需要配置 multipartResolver bean，使用类org.springframework.web.multipart.commons.CommonsMultipartResolver。

<!-- 定义文件上传解析器 -->
<bean id="multipartResolver" class="org.springframework.web.multipart.commons.CommonsMultipartResolver">
<!-- 设定默认编码 -->
    <property name="defaultEncoding" value="UTF-8"></property>
    <!-- 设定文件上传的最大值10MB，10*1024*1024 -->
    <property name="maxUploadSize" value="10485760"></property>
</bean>

Controller

import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileOutputStream;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
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.RequestParam;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.multipart.MultipartFile;

/**
 * Handles requests for the application file upload requests
 */
@Controller
public class FileUploadController {

    private static final Logger logger = LoggerFactory
            .getLogger(FileUploadController.class);

    /**
     * Upload single file using Spring Controller
     */
    @RequestMapping(value = "/uploadFile", method = RequestMethod.POST)
    public @ResponseBody
    String uploadFileHandler(@RequestParam("name") String name,
            @RequestParam("file") MultipartFile file) {

        if (!file.isEmpty()) {
            try {
                byte[] bytes = file.getBytes();

                // Creating the directory to store file
                String rootPath = System.getProperty("catalina.home");
                File dir = new File(rootPath + File.separator + "tmpFiles");
                if (!dir.exists())
                    dir.mkdirs();

                // Create the file on server
                File serverFile = new File(dir.getAbsolutePath()
                        + File.separator + name);
                BufferedOutputStream stream = new BufferedOutputStream(
                        new FileOutputStream(serverFile));
                stream.write(bytes);
                stream.close();

                logger.info("Server File Location="
                        + serverFile.getAbsolutePath());

                return "You successfully uploaded file=" + name;
            } catch (Exception e) {
                return "You failed to upload " + name + " => " + e.getMessage();
            }
        } else {
            return "You failed to upload " + name
                    + " because the file was empty.";
        }
    }

    /**
     * Upload multiple file using Spring Controller
     */
    @RequestMapping(value = "/uploadMultipleFile", method = RequestMethod.POST)
    public @ResponseBody
    String uploadMultipleFileHandler(@RequestParam("name") String[] names,
            @RequestParam("file") MultipartFile[] files) {

        if (files.length != names.length)
            return "Mandatory information missing";

        String message = "";
        for (int i = 0; i < files.length; i++) {
            MultipartFile file = files[i];
            String name = names[i];
            try {
                byte[] bytes = file.getBytes();

                // Creating the directory to store file
                String rootPath = System.getProperty("catalina.home");
                File dir = new File(rootPath + File.separator + "tmpFiles");
                if (!dir.exists())
                    dir.mkdirs();

                // Create the file on server
                File serverFile = new File(dir.getAbsolutePath()
                        + File.separator + name);
                BufferedOutputStream stream = new BufferedOutputStream(
                        new FileOutputStream(serverFile));
                stream.write(bytes);
                stream.close();

                logger.info("Server File Location="
                        + serverFile.getAbsolutePath());

                message = message + "You successfully uploaded file=" + name
                        + "
";
            } catch (Exception e) {
                return "You failed to upload " + name + " => " + e.getMessage();
            }
        }
        return message;
    }
}

参考

• Ref 1
• Ref 2