SpringMVC 本地文件上传+跨服务器文件上传

た入场券 2022-01-22 09:13 354阅读 0赞

### 一、 本地文件上传 ###

先导入两个jar包依赖坐标

1. 文件上传的jsp页面  注意form标签中的 entype属性需设置为multipart/form-data

<%@ page contentType="text/html;charset=UTF-8" language="java" %>
    <html>
    <head>
        <title>Title</title>
    </head>
    <body>
    <form action="/user/fileupload" method="post" enctype="multipart/form-data">
        <INPUT TYPE="file" name="upload"/>
    <br/>
        <input type="submit" value="提交">
    </form>
    </body>
    </html>

2. controller控制页面

这里用到了MultipartFile 对象 主要是用来文件上传

package com.qst.Controller;
    
    
    import org.springframework.stereotype.Controller;
    import org.springframework.web.bind.annotation.RequestMapping;
    import org.springframework.web.multipart.MultipartFile;
    import javax.servlet.http.HttpServletRequest;
    import java.io.File;
    import java.util.UUID;
    @Controller
    @RequestMapping("/user")
    public class UserController {
    
        @RequestMapping("/fileupload")
      public String fileupload(HttpServletRequest request , MultipartFile upload) throws Exception {
    
            System.out.println("上传。。。");
    
            String path = request.getSession().getServletContext().getRealPath("uploads");
    
            //判断该路径是否存在
            File file = new File(path);
            if(!file.exists()){
                //如果不存在则创建一个目录
                file.mkdirs();
            }
    
            //获取上传文件的名称
            String filename = upload.getOriginalFilename();
            //把文件名设置成一个唯一值
            String uid = UUID.randomUUID().toString().replace("-","");
      
            filename = uid + "_" + filename;
          
    
            //完成文件上传 , 将文件存放到 path 指定目录下 并 把名字设置为 filename 指定的名字
            upload.transferTo(new File(path,filename));
            return "success";
      }
    }

3. 配置文件解析器

这里bean的id必须为multipartResolver  ，bean里还可以添加一些参数 如设置上传文件的大小的最大值

<bean id="multipartResolver" class="org.springframework.web.multipart.commons.CommonsMultipartResolver">
    
            <property name="maxUploadSize" value="10000000"/>
        </bean>

### 二、跨服务器文件上传 ###

先导jar包

<dependency>
          <groupId>commons-fileupload</groupId>
          <artifactId>commons-fileupload</artifactId>
          <version>1.3.1</version>
        </dependency>
        
        <dependency>
          <groupId>commons-io</groupId>
          <artifactId>commons-io</artifactId>
          <version>2.4</version>
        </dependency>
        
        <dependency>
          <groupId>com.sun.jersey</groupId>
          <artifactId>jersey-client</artifactId>
          <version>1.19</version>
        </dependency>
        
        <dependency>
          <groupId>com.sun.jersey</groupId>
          <artifactId>jersey-core</artifactId>
          <version>1.19</version>
        </dependency>
    
      </dependencies>

创建连个服务器一个用于接收文件，一个用于上传文件。设置不同端口号

在接收文件的服务器项目中 需要开启一个支持写操作

在web.xml中加入

<servlet>
        <servlet-name>default</servlet-name>
        <servlet-class>org.apache.catalina.servlets.DefaultServlet</servlet-class>
        <init-param>
          <param-name>debug</param-name>
          <param-value>0</param-value>
        </init-param>
        <init-param>
          <param-name>readonly</param-name>
          <param-value>false</param-value>
        </init-param>
        <init-param>
          <param-name>listings</param-name>
          <param-value>false</param-value>
        </init-param>
        <load-on-startup>1</load-on-startup>
      </servlet>
      <servlet-mapping>
        <servlet-name>default</servlet-name>
        <url-pattern>/</url-pattern>
            </servlet-mapping>

1. jsp页面也普通上传文件一样

<%@ page contentType="text/html;charset=UTF-8" language="java" %>
    <html>
    <head>
        <title>Title</title>
    </head>
    <body>
    <form action="/user/fileuploadServer" method="post" enctype="multipart/form-data">
        <INPUT TYPE="file" name="upload"/>
    <br/>
        <input type="submit" value="提交">
    </form>
    </body>
    </html>

controller

package com.qst.Controller;
    
    
    import com.sun.jersey.api.client.Client;
    import com.sun.jersey.api.client.WebResource;
    import org.springframework.stereotype.Controller;
    import org.springframework.web.bind.annotation.RequestMapping;
    import org.springframework.web.multipart.MultipartFile;
    import javax.servlet.http.HttpServletRequest;
    import java.io.File;
    import java.util.UUID;
    @Controller
    @RequestMapping("/user")
    public class UserController {
    
    
        @RequestMapping("/fileuploadServer")
        public String fileuploadServer(MultipartFile upload) throws Exception {
    
            //设置上传服务器的路径 要保证有loads这个目录
            String path = "http://localhost:8089/loads";
    
            //获取上传文件的名称
            String filename = upload.getOriginalFilename();
            //把文件名设置成一个唯一值
            String uid = UUID.randomUUID().toString().replace("-","");
    
            filename = uid + "_" + filename;
    //创建客户端对象
            Client client = Client.create();
    //与服务器进行连接
            WebResource webResource = client.resource(path + filename);
    //进行文件上传，并将文件转换成字节流
            webResource.put(upload.getBytes());
    
    
            return "success";
        }
    }

进行上传时需先开启接收文件的也服务器