• 使用传统javaweb进行文件上传


    使用传统文件上传方式

    1、配置依赖

      <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <maven.compiler.source>1.7</maven.compiler.source>
        <maven.compiler.target>1.7</maven.compiler.target>
        <spring.version>5.0.2.RELEASE</spring.version>
      </properties>
    
      <dependencies>
        <!-- spring -->
        <dependency>
          <groupId>org.aspectj</groupId>
          <artifactId>aspectjweaver</artifactId>
          <version>1.6.8</version>
        </dependency>
    
        <dependency>
          <groupId>org.springframework</groupId>
          <artifactId>spring-aop</artifactId>
          <version>${spring.version}</version>
        </dependency>
    
        <dependency>
          <groupId>org.springframework</groupId>
          <artifactId>spring-context</artifactId>
          <version>${spring.version}</version>
        </dependency>
    
        <dependency>
          <groupId>org.springframework</groupId>
          <artifactId>spring-context-support</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-orm</artifactId>
          <version>${spring.version}</version>
        </dependency>
    
        <dependency>
          <groupId>org.springframework</groupId>
          <artifactId>spring-beans</artifactId>
          <version>${spring.version}</version>
        </dependency>
    
        <dependency>
          <groupId>org.springframework</groupId>
          <artifactId>spring-core</artifactId>
          <version>${spring.version}</version>
        </dependency>
    
        <dependency>
          <groupId>org.springframework</groupId>
          <artifactId>spring-test</artifactId>
          <version>${spring.version}</version>
        </dependency>
    
        <dependency>
          <groupId>org.springframework</groupId>
          <artifactId>spring-webmvc</artifactId>
          <version>${spring.version}</version>
        </dependency>
    
        <dependency>
          <groupId>org.springframework</groupId>
          <artifactId>spring-tx</artifactId>
          <version>${spring.version}</version>
        </dependency>
    
        <dependency>
          <groupId>junit</groupId>
          <artifactId>junit</artifactId>
          <version>4.12</version>
          <scope>compile</scope>
        </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>
    
        <!-- javaweb传统文件上传-->
        <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>jstl</groupId>
          <artifactId>jstl</artifactId>
          <version>1.2</version>
        </dependency>
    
    
        <dependency>
          <groupId>junit</groupId>
          <artifactId>junit</artifactId>
          <version>4.11</version>
          <scope>test</scope>
        </dependency>
      </dependencies>

    2、配置web.xml

    <!DOCTYPE web-app PUBLIC
     "-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN"
     "http://java.sun.com/dtd/web-app_2_3.dtd" >
    
    <web-app>
      <display-name>Archetype Created Web Application</display-name>
    
      <!--配置前端控制器-->
      <servlet>
        <servlet-name>dispatcherServlet</servlet-name>
        <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
        <!--加载springmvc.xml配置文件-->
        <init-param>
          <param-name>contextConfigLocation</param-name>
          <param-value>classpath:springmvc.xml</param-value>
        </init-param>
        <!--启动服务器,创建该servlet-->
        <load-on-startup>1</load-on-startup>
      </servlet>
      <servlet-mapping>
        <servlet-name>dispatcherServlet</servlet-name>
        <url-pattern>/</url-pattern>
      </servlet-mapping>
    
      <!--解决中文乱码的过滤器-->
      <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>
      </filter>
      <filter-mapping>
        <filter-name>characterEncodingFilter</filter-name>
        <url-pattern>/*</url-pattern>
      </filter-mapping>
    </web-app>

    3、配置springmvc.xml(注意配置视图解析器对象 )

    <?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">
    
        <!--开启注解扫描,只扫描Controller注解-->
        <context:component-scan base-package="cn.flypig666">
            <context:include-filter type="annotation" expression="org.springframework.stereotype.Controller"/>
        </context:component-scan>
    
        <!--配置的视图解析器对象-->
        <bean id="internalResourceViewResolver" class="org.springframework.web.servlet.view.InternalResourceViewResolver">
            <property name="prefix" value="/WEB-INF/pages/"/>
            <property name="suffix" value=".jsp"/>
        </bean>
    
        <!--&lt;!&ndash;配置的视图解析器对象&ndash;&gt;-->
        <!--<bean id="internalResourceViewResolver" class="org.springframework.web.servlet.view.InternalResourceViewResolver">-->
        <!--<property name="prefix" value="/WEB-INF/pages/"/>-->
        <!--<property name="suffix" value=".jsp"/>-->
        <!--</bean>-->
        <!--过滤静态资源-->
        <!--<mvc:resources location="/css/" mapping="/css/**" />-->
        <!--<mvc:resources location="/fonts/" mapping="/fonts/**"/>-->
        <!--<mvc:resources location="/images/" mapping="/images/**" />-->
        <!--<mvc:resources location="/js/" mapping="/js/**" />-->
        <!--开启SpringMVC注解的支持-->
        <mvc:annotation-driven/>
    
    </beans>

    4、编写jsp

        <h3>文件上传</h3>
        <form action="file/upload1" method="post" enctype="multipart/form-data">
            选择文件:<input type="file" name="upload1" /><br/>
            <input type="submit" value="上传" />
        </form>

    5、编写controller

    @Controller
    @RequestMapping("/file")
    public class UploadFileController {
    
        @RequestMapping("/upload1")
        public String fileupload1(HttpServletRequest request) throws Exception {
            System.out.println("文件上传");
    
            // 使用fileupload组件完成组件上传
            // 上传的位置
            // request.getSession().getServletContext():拿到最大的域对象,getRealPath():拿到某路径下的绝对路径
            String path = request.getSession().getServletContext().getRealPath("/uploads/");
            // 判断该路径是否存在
            File file = new File(path);
            if (!file.exists()){
                // 创建文件夹
                file.mkdirs();
            }
    
            // 解析request对象,获取上传文件项
            // 创建磁盘文件项工厂
            DiskFileItemFactory factory = new DiskFileItemFactory();
            ServletFileUpload upload = new ServletFileUpload(factory);
            // 解析request,返回一个list集合,集合里是文件项
            List<FileItem> items = upload.parseRequest(request);
            // 遍历
            for (FileItem item:items){
                // 进行判断,当前item对象是否是上传文件项
                if (item.isFormField()){
                    // true说明普通表单向
                }else{
                    // false说明是上传文件项
                    // 获取上传文件名
                    String filename = item.getName();
                    // 把文件的名称设置为唯一值,uuid
                    String uuid = UUID.randomUUID().toString().replace("-", "");
                    filename = uuid + "_" + filename;
                    // 完成文件上传
                    item.write(new File(path,filename));
                    // 删除临时文件,由于传统web上传会产生一个临时文件(>10kb)
                    item.delete();
                }
            }
    
            return "success";
        }
    }
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  • 原文地址:https://www.cnblogs.com/flypig666/p/11745182.html
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