环境的搭建
用idea创建java Enterprise项目，手动添加Tomcat。
在resources目录下创建Spring的配置文件。
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:aop="http://www.springframework.org/schema/aop"
xmlns:mvc="http://www.springframework.org/schema/mvc"
xmlns:tx="http://www.springframework.org/schema/tx"
xmlns:context="http://www.springframework.org/schema/context"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx.xsd
http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop.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">
<!--开启注解配置-->
<context:component-scan base-package="xin.students"/>
<context:annotation-config/>
<!--开启注Aspect生成代理对象-->
<aop:aspectj-autoproxy/>
<!--开启mvc注解配置-->
<mvc:annotation-driven/>
<mvc:resources mapping="/js/**" location="/js/"/>
<mvc:resources mapping="/css/**" location="/css/"/>
<mvc:resources mapping="/imgs/**" location="/imgs/"/>
<bean id="multipartResolver" class="org.springframework.web.multipart.commons.CommonsMultipartResolver">
<!--上传文件的最大大小-->
<property name="maxUploadSizePerFile" value="20140000"/>
<!--缓存大小-->
<property name="maxInMemorySize" value="102400"/>
<!--文件编码-->
<property name="defaultEncoding" value="utf-8"/>
</bean>
</beans>maven依赖
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>xin.students</groupId>
<artifactId>SpringMVC-File-down-update</artifactId>
<version>1.0-SNAPSHOT</version>
<name>SpringMVC-File-down-update</name>
<packaging>war</packaging>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<maven.compiler.target>1.8</maven.compiler.target>
<maven.compiler.source>1.8</maven.compiler.source>
<junit.version>5.7.1</junit.version>
<spring-version>5.3.16</spring-version>
</properties>
<dependencies>
<dependency>
<groupId>javax.servlet</groupId>
<artifactId>javax.servlet-api</artifactId>
<version>4.0.1</version>
<scope>provided</scope>
</dependency>
<dependency>
<groupId>org.junit.jupiter</groupId>
<artifactId>junit-jupiter-api</artifactId>
<version>${junit.version}</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.junit.jupiter</groupId>
<artifactId>junit-jupiter-engine</artifactId>
<version>${junit.version}</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-context</artifactId>
<version>${spring-version}</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-aspects</artifactId>
<version>${spring-version}</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-jdbc</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-web</artifactId>
<version>${spring-version}</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-webmvc</artifactId>
<version>${spring-version}</version>
</dependency>
<!--spring-mvc的JSON转换工具依赖-->
<dependency>
<groupId>com.fasterxml.jackson.core</groupId>
<artifactId>jackson-databind</artifactId>
<version>2.13.1</version>
</dependency>
<dependency>
<groupId>commons-io</groupId>
<artifactId>commons-io</artifactId>
<version>2.4</version>
</dependency>
<dependency>
<groupId>commons-fileupload</groupId>
<artifactId>commons-fileupload</artifactId>
<version>1.4</version>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-war-plugin</artifactId>
<version>3.3.1</version>
</plugin>
</plugins>
</build>
</project>web.xml
<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_4_0.xsd"
version="4.0">
<servlet>
<servlet-name>springmvc</servlet-name>
<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
<init-param>
<param-name>contextConfigLocation</param-name>
<param-value>classpath:spring-servlet.xml</param-value>
</init-param>
</servlet>
<servlet-mapping>
<servlet-name>springmvc</servlet-name>
<url-pattern>/</url-pattern>
</servlet-mapping>
<filter>
<filter-name>EncodingFilter</filter-name>
<filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class>
<!--设置编码器的编码-->
<init-param>
<param-name>encoding</param-name>
<param-value>utf-8</param-value>
</init-param>
<!--开启强制编码-->
<init-param>
<param-name>forceEncoding</param-name>
<param-value>true</param-value>
</init-param>
</filter>
<filter-mapping>
<filter-name>EncodingFilter</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
</web-app>index.jsp文件
<%@ page contentType="text/html; charset=UTF-8" pageEncoding="UTF-8" %>
<!DOCTYPE html>
<html>
<head>
<title>JSP - Hello World</title>
</head>
<body>
<table width="100%" height="700px">
<td width="200px" style="border-right: deepskyblue 2px solid; background-color: rgba(255,0,0,0.1)">
<ul>
<li><a href="book-add.jsp" target="mainFrame">添加图书</a></li
<li><a href="#">图书列表</a></li>
<li><a href="tisp.jsp" target="mainFrame">图书列表</a></li>
</ul>
</td>
<td>
<iframe name="mainFrame" width="100%" height="700px" frameborder="2px"></iframe>
</td>
</table>
</body>
</html>book-add.jsp
<%@ page contentType="text/html; charset=UTF-8" pageEncoding="UTF-8" %>
<!DOCTYPE html>
<html>
<head>
<title>JSP - Hello World</title>
</head>
<body>
<h4>添加图书信息</h4>
<form action="/book/add" method="post" enctype="multipart/form-data">
<p>图书名称:<input type="text" name="bookName"></p>
<p>图书作者:<input type="text" name="bookAuthor"></p>
<p>图书价格:<input type="text" name="bookPrice"></p>
<p>图书明面:<input type="file" name="imgFile"></p>
<p><input type="submit" value="提交"></p>
</form>
</body>
</html>Book.java
package xin.students.beans;
public class Book {
private Integer bookId;
private String bookName;
private String bookAuthor;
private Double bookPrice;
private String bookImg;
public Book() {
}
public Book(Integer bookId, String bookName, String bookAuthor, Double bookPrice, String bookImg) {
this.bookId = bookId;
this.bookName = bookName;
this.bookAuthor = bookAuthor;
this.bookPrice = bookPrice;
this.bookImg = bookImg;
}
public Integer getBookId() {
return bookId;
}
public void setBookId(Integer bookId) {
this.bookId = bookId;
}
public String getBookName() {
return bookName;
}
public void setBookName(String bookName) {
this.bookName = bookName;
}
public String getBookAuthor() {
return bookAuthor;
}
public void setBookAuthor(String bookAuthor) {
this.bookAuthor = bookAuthor;
}
public Double getBookPrice() {
return bookPrice;
}
public void setBookPrice(Double bookPrice) {
this.bookPrice = bookPrice;
}
public String getBookImg() {
return bookImg;
}
public void setBookImg(String bookImg) {
this.bookImg = bookImg;
}
@Override
public String toString() {
return "Book{" +
"bookId=" + bookId +
", bookName='" + bookName + '\'' +
", bookAuthor='" + bookAuthor + '\'' +
", bookPrice=" + bookPrice +
", bookImg='" + bookImg + '\'' +
'}';
}
}
文件的上传
前端上传文件
<h4>添加图书信息</h4>
<form action="/book/add" method="post" enctype="multipart/form-data">
<p>图书名称:<input type="text" name="bookName"></p>
<p>图书作者:<input type="text" name="bookAuthor"></p>
<p>图书价格:<input type="text" name="bookPrice"></p>
<p>图书明面:<input type="file" name="imgFile"></p>
<p><input type="submit" value="提交"></p>
</form>控制器接收数据和文件
SpringMVC处理上传文件需要借助CommonsMultipartResolver文件解析器
添加依赖：commons-io commons-fileupload
<dependency>
<groupId>commons-io</groupId>
<artifactId>commons-io</artifactId>
<version>2.4</version>
</dependency>
<dependency>
<groupId>commons-fileupload</groupId>
<artifactId>commons-fileupload</artifactId>
<version>1.4</version>
</dependency>在spring-servlet.xml中配置文件解析器
<bean id="multipartResolver" class="org.springframework.web.multipart.commons.CommonsMultipartResolver">
<!--上传文件的最大大小-->
<property name="maxUploadSizePerFile" value="20140000"/>
<!--缓存大小-->
<property name="maxInMemorySize" value="102400"/>
<!--文件编码-->
<property name="defaultEncoding" value="utf-8"/>
<!--接收到的文件存储位置-->
<property name="uploadTempDir" value="C:\\Users\\Administrator\\Desktop\\"/>
</bean>控制器接收文件
在处理文件上传的方法中定义一个MultPartFile类型的对象，就可以接收图片了。
@Controller
@RequestMapping("/book")
public class BookController {
@RequestMapping("/add")
public String addBook(Book book, MultipartFile imgFile, HttpServletRequest request) throws IOException {
//获取文件名
String originalFilename = imgFile.getOriginalFilename();
//截取文件的后缀名
String ext = originalFilename.substring(originalFilename.lastIndexOf("."));
//获取imgs目录在服务器中的绝对路径
String dir = request.getServletContext().getRealPath("imgs");
//获取当前毫秒值生成文件名
String fileName = System.currentTimeMillis() + ext;
//设置文件的绝对路径
String savePath = dir + "/" + fileName;
//写入到指定路径
imgFile.transferTo(new File(savePath));
return "/tisp.jsp";
}
}文件的下载
前端代码
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
<title>文件列表</title>
<script src="js/jquery-3.6.0.js"></script>
<!-- 最新版本的 Bootstrap 核心 CSS 文件 -->
<link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/3.4.1/css/bootstrap.min.css"
integrity="sha384-HSMxcRTRxnN+Bdg0JdbxYKrThecOKuH5zCYotlSAcp1+c8xmyTe9GYg1l9a69psu" crossorigin="anonymous">
<!-- 可选的 Bootstrap 主题文件（一般不用引入） -->
<link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/3.4.1/css/bootstrap-theme.min.css"
integrity="sha384-6pzBo3FDv/PJ8r2KRkGHifhEocL+1X2rVCTTkUfGk7/0pbek5mMa1upzvWbrUbOZ" crossorigin="anonymous">
<!-- 最新的 Bootstrap 核心 JavaScript 文件 -->
<script src="https://stackpath.bootstrapcdn.com/bootstrap/3.4.1/js/bootstrap.min.js"
integrity="sha384-aJ21OjlMXNL5UyIl/XNwTMqvzeRMZH2w8c5cRVpzpU8Y5bApTppSuUkhZXN0VxHd"
crossorigin="anonymous"></script>
</head>
<style>
img {
height: 70%;
margin-right: 50px;
}
</style>
<script>
$(function () {
$.get("/book/list", function (res) {
for (let i = 0, len = res.length; i < len; i++) {
let imgName = res[i];
let htmlStr = "<div class='col-lg-2 col-md-4 col-sm-6'><div class='thumbnail'><img src='imgs/" + imgName + "' alt=''><div class='caption'><p><a href='book/download?fileName=" + imgName + "' class='btn btn-primary' role='button'>Download</a></p></div></div></div>"
$("#container").append(htmlStr);
}
})
}, "json");
</script>
<body>
<h1>图片列表</h1>
<div class="row" id="container">
</div>
</body>
</html>
后盾代码
@Controller
@RequestMapping("/book")
public class BookController {
@RequestMapping("/list")
@ResponseBody
public String[] listImages(HttpServletRequest request) {
//获取目录信息
String dir = request.getServletContext().getRealPath("imgs");
File imgDir = new File(dir);
//返回文件夹下的所有文件名
String[] file = imgDir.list();
return file;
}
@RequestMapping("/download")
public void download(String fileName, HttpServletRequest request, HttpServletResponse response) throws Exception {
String dirPath = request.getServletContext().getRealPath("imgs");
String filePath = dirPath + "/" + fileName;
FileInputStream fileInputStream = new FileInputStream(filePath);
//设置相应的文件类型,类型要写成浏览器不能显示的,可以随便写
response.setContentType("application/exe");
//设置相应头和要保存的文件名
response.addHeader("Content-Disposition", "attachment;filename=" + fileName);
//org.apache.commons.io.IOUtils包下的,把文件流返回给用户流
IOUtils.copy(fileInputStream, response.getOutputStream());
}
}
