系列5、springMVC實現文件上傳和跨服務器上傳文件

時間 2019-11-11

原文原文鏈接

1、實現文件上傳

項目目錄以下所示javascript

1、導入依賴和配置springmvc.xml、web.xml

這個兩個jar包是實現文件上傳必需要導入的包css

<resources>
            <!-- mapper.xml文件在java目錄下 -->
            <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>
        <!--編譯版本修改-->
        <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>
        <!--文件上傳組件-->
        <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建立容器時要掃描的包 -->
    <context:component-scan base-package="com.cc"></context:component-scan>

    <!-- 配置視圖解析器：返回請求成功後的頁面 -->
    <bean id="viewResolver" class="org.springframework.web.servlet.view.InternalResourceViewResolver">
        <!--文件所在的目錄:相對路徑-->
        <property name="prefix" value="/pages/"></property>
        <!--文件的後綴名-->
        <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>

    <!--配置攔截器-->
    <mvc:interceptors>
        <mvc:interceptor>
            <!--那些方法攔截-->
            <mvc:mapping path="/student/*"/>
            <!--註冊攔截器對象-->
            <bean class="com.cc.controller.HandlerInterceptorDemo"></bean>
        </mvc:interceptor>
    </mvc:interceptors>

    <!--告訴前端控制器，那些靜態資源不攔截-->
    <!--<mvc:resources location="/css/" mapping="/css/**"/> &lt;!&ndash; 樣式 &ndash;&gt;
    <mvc:resources location="/images/" mapping="/images/**"/> &lt;!&ndash; 圖片 &ndash;&gt;-->
    <!--<mvc:resources location="/js/" mapping="/js/**"/> --><!-- javascript -->

    <!--配置spring開啓註解mvc的支持-->
    <mvc:annotation-driven/>
</beans>

2、編寫controller層代碼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>
    <!-- 而後配置Servlet的初始化參數，讀取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啓動時加載對象 -->
    <load-on-startup>1</load-on-startup>
  </servlet>

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

  <!--配置過濾器解決中文亂碼：提供初始化參數-->
  <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>
    <!-- 啓動過濾器 -->
    <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 {
    /**
     * 文件上傳,之前傳統的方式
     * @return
     */
    @RequestMapping("fileupload1")
    public String fileupload1(HttpServletRequest request) throws Exception {
        System.out.println("fileupload is success.....");
        //使用fileupload組件實現文件上傳
        //指定文件上傳的位置
        String path=request.getSession().getServletContext().getRealPath("/upload/");
        //判斷該路徑是否存在
        File file=new File(path);
        if(!file.exists()){
            //不存在就建立一個路徑
            file.mkdirs();
        }
        //解析request對象，獲取文件上傳項
        DiskFileItemFactory factory=new DiskFileItemFactory();
        ServletFileUpload upload=new ServletFileUpload(factory);
        //解析request
        List<FileItem> item =upload.parseRequest(request);
        //判斷當前的item對象是否爲上傳文件項
        for (FileItem items :item)
            if (items.isFormField()) {
                //說明是普通表單項
            } else {
                //說明上傳文件項
                //獲取上傳文件的名稱
                String filename = items.getName();
                //把文件名稱設置成惟一值uuid
                String uuid=UUID.randomUUID().toString().replace("-"," ");
                filename=uuid+"_"+filename;
                //完成上傳文件
                items.write(new File(path,filename));
                //刪除臨時文件
                items.delete();
            }
        return "success";
    }

    /**
     * 文件上傳,springmvc方式
     * @return
     */
    @RequestMapping("fileupload2")
    public String fileupload2(HttpServletRequest request, MultipartFile upload) throws Exception {
        System.out.println("fileupload is success.....");
        //指定文件上傳的位置
        String path=request.getSession().getServletContext().getRealPath("/upload/");
        //判斷該路徑是否存在
        File file=new File(path);
        if(!file.exists()){
            //不存在就建立一個路徑
            file.mkdirs();
        }
        //說明上傳文件項
        //獲取上傳文件的名稱
        String filename=upload.getOriginalFilename();
        //把文件名稱設置成惟一值uuid
        String uuid=UUID.randomUUID().toString().replace("-","");
        filename=uuid+"_"+filename;
        //完成上傳文件
        upload.transferTo(new File(path,filename));
        return "success";
      }
    }
}

springmvc實現文件上傳幫咱們省了很多事，不用咱們本身再去編寫輸入輸出流，前端

3、編寫jsp測試代碼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>文件上傳</title>
</head>
<body>
     <form action="/student/fileupload1" method="post" enctype="multipart/form-data">
         選擇文件:<input type="file" name="upload" /><br/>
         <input type="submit" value="提交"/>
     </form>
     <%--使用springmvc的方式上傳--%>
     <form action="/student/fileupload2" method="post" enctype="multipart/form-data">
         選擇文件:<input type="file" name="upload" /><br/>
         <input type="submit" value="提交"/>
     </form>
</body>
</html>

這裏一共測試了兩種上傳文件的方式，去相關發佈目錄找上傳的圖片上傳成功web

2、 springmvc 跨服務器方式的文件上傳

在實際開發中，咱們會有不少處理不一樣功能的服務器。例如：
應用服務器：負責部署咱們的應用
數據庫服務器：運行咱們的數據庫
緩存和消息服務器：負責處理大併發訪問的緩存和消息
文件服務器：負責存儲用戶上傳文件的服務器。spring

項目目錄和實現步驟以下，實現fileupload文件上傳到service服務器上數據庫

①準備兩個 tomcat 服務器，並建立一個用於存放圖片的 web 工程apache

②導入須要實現服務器的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層頁面代碼

<%--使用跨服務器方式上傳文件--%>
     <form action="/student/fileupload3" method="post" enctype="multipart/form-data">
         選擇文件:<input type="file" name="upload" /><br/>
         <input type="submit" value="提交"/>
     </form>

④controller層頁面代碼

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

        // 定義上傳文件服務器路徑
        String path = "http://localhost:9090/uploads/";

        // 說明上傳文件項
        // 獲取上傳文件的名稱
        String filename = upload.getOriginalFilename();
        // 把文件的名稱設置惟一值，uuid
        String uuid = UUID.randomUUID().toString().replace("-", "");
        filename = uuid+"_"+filename;

        // 建立客戶端的對象
        Client client = Client.create();

        // 和圖片服務器進行鏈接
        WebResource webResource = client.resource(path+filename);

        // 上傳文件
        webResource.put(upload.getBytes());

        return "success";
    }