本文介绍了通过导入架包的方式与使用maven依赖的方式分别使用springmvc框架实现单文件的上传主要逻辑流程，多文件上传留作后续更新。�
一 、 导入架包实现Spring MVC 文件上传到服务器本地
除了spring 架包外还需要org.apache.commons-fileupload-x.x.x.ja包的支持
springmvc.xml 中配置bean
<!-- 处理文件上传 -->
<!-- id="multipartResolver" 属于spring文件装配时的一个属性，名称固定不能改变！！！！ -->
<bean id="multipartResolver"
class="org.springframework.web.multipart.commons.CommonsMultipartResolver" >
<property name="defaultEncoding" value="utf-8"/> <!-- 默认编码 (ISO-8859-1) -->
<property name="maxInMemorySize" value="10240"/> <!-- 最大内存大小 (10240) -->
<property name="uploadTempDir" value="/upload/"/> <!-- 上传后的目录名 (WebUtils#TEMP_DIR_CONTEXT_ATTRIBUTE) -->
<property name="maxUploadSize" value="-1"/><!-- 最大文件大小，-1为无限止(-1) -->
</bean>
jsp 界面的处理 特别注意单词的拼写：
enctype = "multipart/form-data"
<form action="/RestMyibatisSpring/file/upload" method="post" enctype = "multipart/form-data">
<!-- <input type = "hidden" name = "method" value ="upload"> -->
<input type = "text" name = "fileName" >
<input type = "file" name = "file" >
<input type = "submit" value = "上传文件">
</form>
设置相应的controller处理
import java.io.File;
import javax.servlet.ServletContext;
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.context.ServletContextAware;
import org.springframework.web.multipart.commons.CommonsMultipartFile;
@Controller
@RequestMapping("/file")
public class FileController_Rest implements ServletContextAware{
private ServletContext servletContext;
@Override
public void setServletContext(ServletContext arg0) {
this.servletContext = arg0;
}
@RequestMapping(value="/upload",method = RequestMethod.POST)
public String uploadFile(String fileName,@RequestParam("file")CommonsMultipartFile file) {
if (!file.isEmpty()) {
String path = this.servletContext.getRealPath("/upload");
String oriFileName = file.getOriginalFilename();
String fileType = oriFileName.substring(oriFileName.lastIndexOf("."));
String newFileName = fileName + fileType;
File newFile = new File(path + "/" + newFileName);
try {
file.getFileItem().write(newFile);
} catch (Exception e) {
e.printStackTrace();
}
}
return "/jsps/upload";
}
}
二、 maven 使用spring 上传文件到hdfs系统
spring使用文件上传功能处理springmvc的基础包之外还需要两个库
commons-fileupload-1.2.2.jar，commons-io-2.0.1.jar的支持
使用maven的直接导入commons-fileupload依赖就可以了，commons-fileupload会自动下载io依赖包
<!-- https://mvnrepository.com/artifact/commons-fileupload/commons-fileupload -->
<dependency>
<groupId>commons-fileupload</groupId>
<artifactId>commons-fileupload</artifactId>
<version>1.3.2</version>
</dependency>
![enter description here][4]
然后springmvc.xml中要配置spring的相关依赖
<bean id="multipartResolver" class="org.springframework.web.multipart.commons.CommonsMultipartResolver">
<property name="defaultEncoding" value="utf-8"/>
</bean>
jsp界面代码如下
<form id="uploadFile" action="/cd/fileIndex/uploadFile" method="post" enctype="multipart/form-data">
<div class=":form-group">
<label>选择文件</label>
<input id="file" type="file" name="file" class="form-control"/>
<input type="hidden" name="parentId" value="<%=rootDir.getFileIndexId()%>"/>
<input type="hidden" name="parentPath" value="<%=rootDir.getPath()%>"/>
</div>
</form>
Java代码如下
controller
@RequestMapping(value="/uploadFile",method=RequestMethod.POST)
public String uploadFile(@RequestParam(value="file",required=false) MultipartFile file
,@SessionAttribute("loginUser") AppUser loginUser,String parentId,String parentPath)
throws IllegalArgumentException, IOException, NoSuchAlgorithmException{
//接受前台传输过来的文件并保存在hdfs上
String fileName = file.getOriginalFilename();
InputStream fStream = file.getInputStream();
Long fileSize = file.getSize();
String pathStr = "/user/root/clouddisk/" + fileName;
String md5 = HDFSUtil.upLoadFileToHdfs(fStream, pathStr);
return "redirect:/fileIndex/openDirectory?dirId=" + parentId;
}
HDFSUtil.java
import java.io.IOException;
import java.io.InputStream;
import java.math.BigInteger;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.util.Arrays;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FSDataOutputStream;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
public class HDFSUtil {
public static final Configuration CONFIGURATION = new Configuration();
// 获取FileSystem 对象
public static FileSystem getFileSystem() {
try {
return FileSystem.get(CONFIGURATION);
} catch (IOException e) {
e.printStackTrace();
return null;
}
}
public static String upLoadFileToHdfs(InputStream iStream, String pathStr)
throws IllegalArgumentException, IOException, NoSuchAlgorithmException {
FileSystem fileSystem = HDFSUtil.getFileSystem();
FSDataOutputStream outputStream = fileSystem.create(new Path(pathStr));
byte[] buffer = new byte[1024];
MessageDigest mDigest = MessageDigest.getInstance("MD5");
int lenth = iStream.read(buffer,0,1024);
while (lenth > -1) {
//保证文件不失真
if (lenth < 1024) {
byte[] lastBuffer = Arrays.copyOf(buffer, lenth);
mDigest.update(lastBuffer);
outputStream.write(lastBuffer);
} else {
mDigest.update(buffer);
outputStream.write(buffer);
}
lenth = iStream.read(buffer, 0, lenth);
System.out.println("read" + lenth);
}
outputStream.hsync();
outputStream.close();
iStream.close();
fileSystem.close();
BigInteger bigInteger = new BigInteger(1, mDigest.digest());
return bigInteger.toString(16);
}
}
