系列5、springMVC实现文件上传和跨服务器上传文件

时间 2019-11-11

原文原文链接

1、实现文件上传

项目目录以下所示javascript

1、导入依赖和配置springmvc.xml、web.xml

这个两个jar包是实现文件上传必需要导入的包css

<resources>
            <!-- mapper.xml文件在java目录下 -->
            <resource>
                <directory>src/main/java</directory>
                <includes>
                    <include>**/*.xml</include>
                </includes>
            </resource>
            <resource>
                <directory>src/main/resources</directory>
                <includes>
                    <include>**/*.properties</include>
                    <include>**/*.xml</include>
                </includes>
            </resource>
        </resources>
    </build>
    <properties>
        <spring.version>5.0.2.RELEASE</spring.version>
        <!--编译版本修改-->
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <maven.compiler.source>1.8</maven.compiler.source>
        <maven.compiler.target>1.8</maven.compiler.target>
    </properties>
    <dependencies>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-context</artifactId>
            <version>${spring.version}</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-web</artifactId>
            <version>${spring.version}</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-webmvc</artifactId>
            <version>${spring.version}</version>
        </dependency>
        <dependency>
            <groupId>javax.servlet</groupId>
            <artifactId>servlet-api</artifactId>
            <version>2.5</version>
            <scope>provided</scope>
        </dependency>
        <dependency>
            <groupId>javax.servlet.jsp</groupId>
            <artifactId>jsp-api</artifactId>
            <version>2.0</version>
            <scope>provided</scope>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-core</artifactId>
            <version>${spring.version}</version>
        </dependency>
        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-databind</artifactId>
            <version>2.9.0</version>
        </dependency>
        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-core</artifactId>
            <version>2.9.0</version>
        </dependency>
        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-annotations</artifactId>
            <version>2.9.0</version>
        </dependency>
        <!--文件上传组件-->
        <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-core</artifactId>
            <version>1.18.1</version>
        </dependency>
        <dependency>
            <groupId>com.sun.jersey</groupId>
            <artifactId>jersey-client</artifactId>
            <version>1.18.1</version>
        </dependency>
    </dependencies>

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:mvc="http://www.springframework.org/schema/mvc"
       xmlns:context="http://www.springframework.org/schema/context"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xsi:schemaLocation="
       http://www.springframework.org/schema/beans
       http://www.springframework.org/schema/beans/spring-beans.xsd
       http://www.springframework.org/schema/mvc
       http://www.springframework.org/schema/mvc/spring-mvc.xsd
       http://www.springframework.org/schema/context
       http://www.springframework.org/schema/context/spring-context.xsd">
    <!-- 配置spring建立容器时要扫描的包 -->
    <context:component-scan base-package="com.cc"></context:component-scan>

    <!-- 配置视图解析器：返回请求成功后的页面 -->
    <bean id="viewResolver" class="org.springframework.web.servlet.view.InternalResourceViewResolver">
        <!--文件所在的目录:相对路径-->
        <property name="prefix" value="/pages/"></property>
        <!--文件的后缀名-->
        <property name="suffix" value=".jsp"></property>
    </bean>

   <!-- 配置文件解析器-->
    <bean id="multipartResolver" class="org.springframework.web.multipart.commons.CommonsMultipartResolver">
        <property name="maxUploadSize" value="10485760"></property>
    </bean>

    <!--配置拦截器-->
    <mvc:interceptors>
        <mvc:interceptor>
            <!--那些方法拦截-->
            <mvc:mapping path="/student/*"/>
            <!--注册拦截器对象-->
            <bean class="com.cc.controller.HandlerInterceptorDemo"></bean>
        </mvc:interceptor>
    </mvc:interceptors>

    <!--告诉前端控制器，那些静态资源不拦截-->
    <!--<mvc:resources location="/css/" mapping="/css/**"/> &lt;!&ndash; 样式 &ndash;&gt;
    <mvc:resources location="/images/" mapping="/images/**"/> &lt;!&ndash; 图片 &ndash;&gt;-->
    <!--<mvc:resources location="/js/" mapping="/js/**"/> --><!-- javascript -->

    <!--配置spring开启注解mvc的支持-->
    <mvc:annotation-driven/>
</beans>

2、编写controller层代码html

<?xml version="1.0" encoding="UTF-8"?>
<web-app version="2.4"
         xmlns="http://java.sun.com/xml/ns/j2ee"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd">

  <!-- SpringMVC的核心控制器:前端控制器-->
  <servlet>
    <servlet-name>dispatcherServlet</servlet-name>
    <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
    <!-- 而后配置Servlet的初始化参数，读取springmvc的配置文件，建立spring容器 -->
    <init-param>
      <param-name>contextConfigLocation</param-name>
      <param-value>classpath:springmvc.xml</param-value>
    </init-param>
    <!-- 首先是：servlet启动时加载对象 -->
    <load-on-startup>1</load-on-startup>
  </servlet>

  <servlet-mapping>
    <servlet-name>dispatcherServlet</servlet-name>
    <url-pattern>/</url-pattern>
  </servlet-mapping>

  <!--配置过滤器解决中文乱码：提供初始化参数-->
  <filter>
    <filter-name>characterEncodingFilter</filter-name>
    <filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class>
    <init-param>
      <param-name>encoding</param-name>
      <param-value>UTF-8</param-value>
    </init-param>
    <!-- 启动过滤器 -->
    <init-param>
      <param-name>forceEncoding</param-name>
      <param-value>true</param-value>
    </init-param>
  </filter>
  <filter-mapping>
    <filter-name>characterEncodingFilter</filter-name>
    <url-pattern>/*</url-pattern>
  </filter-mapping>
</web-app>

package com.cc.controller;
import com.sun.jersey.api.client.Client;
import com.sun.jersey.api.client.WebResource;
import org.apache.commons.fileupload.FileItem;
import org.apache.commons.fileupload.disk.DiskFileItemFactory;
import org.apache.commons.fileupload.servlet.ServletFileUpload;
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.List;
import java.util.UUID;

@Controller
@RequestMapping("/student")
public class StudentController {
    /**
     * 文件上传,之前传统的方式
     * @return
     */
    @RequestMapping("fileupload1")
    public String fileupload1(HttpServletRequest request) throws Exception {
        System.out.println("fileupload is success.....");
        //使用fileupload组件实现文件上传
        //指定文件上传的位置
        String path=request.getSession().getServletContext().getRealPath("/upload/");
        //判断该路径是否存在
        File file=new File(path);
        if(!file.exists()){
            //不存在就建立一个路径
            file.mkdirs();
        }
        //解析request对象，获取文件上传项
        DiskFileItemFactory factory=new DiskFileItemFactory();
        ServletFileUpload upload=new ServletFileUpload(factory);
        //解析request
        List<FileItem> item =upload.parseRequest(request);
        //判断当前的item对象是否为上传文件项
        for (FileItem items :item)
            if (items.isFormField()) {
                //说明是普通表单项
            } else {
                //说明上传文件项
                //获取上传文件的名称
                String filename = items.getName();
                //把文件名称设置成惟一值uuid
                String uuid=UUID.randomUUID().toString().replace("-"," ");
                filename=uuid+"_"+filename;
                //完成上传文件
                items.write(new File(path,filename));
                //删除临时文件
                items.delete();
            }
        return "success";
    }

    /**
     * 文件上传,springmvc方式
     * @return
     */
    @RequestMapping("fileupload2")
    public String fileupload2(HttpServletRequest request, MultipartFile upload) throws Exception {
        System.out.println("fileupload is success.....");
        //指定文件上传的位置
        String path=request.getSession().getServletContext().getRealPath("/upload/");
        //判断该路径是否存在
        File file=new File(path);
        if(!file.exists()){
            //不存在就建立一个路径
            file.mkdirs();
        }
        //说明上传文件项
        //获取上传文件的名称
        String filename=upload.getOriginalFilename();
        //把文件名称设置成惟一值uuid
        String uuid=UUID.randomUUID().toString().replace("-","");
        filename=uuid+"_"+filename;
        //完成上传文件
        upload.transferTo(new File(path,filename));
        return "success";
      }
    }
}

springmvc实现文件上传帮咱们省了很多事，不用咱们本身再去编写输入输出流，前端

3、编写jsp测试代码java

<%--
  Created by IntelliJ IDEA.
  User: Administrator
  Date: 2019/5/30
  Time: 15:59
  To change this template use File | Settings | File Templates.
--%>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
    <title>文件上传</title>
</head>
<body>
     <form action="/student/fileupload1" method="post" enctype="multipart/form-data">
         选择文件:<input type="file" name="upload" /><br/>
         <input type="submit" value="提交"/>
     </form>
     <%--使用springmvc的方式上传--%>
     <form action="/student/fileupload2" method="post" enctype="multipart/form-data">
         选择文件:<input type="file" name="upload" /><br/>
         <input type="submit" value="提交"/>
     </form>
</body>
</html>

这里一共测试了两种上传文件的方式，去相关发布目录找上传的图片上传成功web

2、 springmvc 跨服务器方式的文件上传

在实际开发中，咱们会有不少处理不一样功能的服务器。例如：
应用服务器：负责部署咱们的应用
数据库服务器：运行咱们的数据库
缓存和消息服务器：负责处理大并发访问的缓存和消息
文件服务器：负责存储用户上传文件的服务器。spring

项目目录和实现步骤以下，实现fileupload文件上传到service服务器上数据库

①准备两个 tomcat 服务器，并建立一个用于存放图片的 web 工程apache

②导入须要实现服务器的jar包api

<dependency>
<groupId>com.sun.jersey</groupId>
<artifactId>jersey-core</artifactId>
<version>1.18.1</version>
</dependency>
<dependency>
<groupId>com.sun.jersey</groupId>
<artifactId>jersey-client</artifactId>
<version>1.18.1</version>
</dependency>

③view层页面代码

<%--使用跨服务器方式上传文件--%>
     <form action="/student/fileupload3" method="post" enctype="multipart/form-data">
         选择文件:<input type="file" name="upload" /><br/>
         <input type="submit" value="提交"/>
     </form>

④controller层页面代码

/**
     * 跨服务器文件上传
     * @return
     */
    @RequestMapping("/fileupload3")
    public String fileuoload3(MultipartFile upload) throws Exception {
        System.out.println("service id doing...");

        // 定义上传文件服务器路径
        String path = "http://localhost:9090/uploads/";

        // 说明上传文件项
        // 获取上传文件的名称
        String filename = upload.getOriginalFilename();
        // 把文件的名称设置惟一值，uuid
        String uuid = UUID.randomUUID().toString().replace("-", "");
        filename = uuid+"_"+filename;

        // 建立客户端的对象
        Client client = Client.create();

        // 和图片服务器进行链接
        WebResource webResource = client.resource(path+filename);

        // 上传文件
        webResource.put(upload.getBytes());

        return "success";
    }