【Java Web开发学习】Spring MVC文件上传

时间 2020-05-08

标签 Java Web开发学习 spring mvc 文件上传栏目 Spring 繁體版

原文原文链接

【Java Web开发学习】Spring MVC文件上传html

转载：https://www.cnblogs.com/yangchongxing/p/9290489.htmljava

文件上传有两种实现方式，都比较简单web

方式1、使用StandardServletMultipartResolverspring

依赖Servlet3.0对Multipart请求的支持，须要MultipartConfigElement配置请求的相关参数json

Java配置方式数组

@Bean public MultipartResolver multipartResolver() { return new StandardServletMultipartResolver(); }

在Servlet中指定multipart配置，经过MultipartConfigElement设置上传临时路径，上传文件大小，上传请求的大小。xcode

经过重载protected void customizeRegistration(ServletRegistration.Dynamic registration)方法实现，看代码mvc

package cn.ycx.web.config; import java.io.IOException; import java.util.Properties; import javax.servlet.MultipartConfigElement; import javax.servlet.ServletRegistration; import org.springframework.web.servlet.support.AbstractAnnotationConfigDispatcherServletInitializer; public class ServletInitializer extends AbstractAnnotationConfigDispatcherServletInitializer { // 将一个或多个路径映射到DispatcherServlet上
 @Override protected String[] getServletMappings() { return new String[] {"/"}; } // 返回的带有@Configuration注解的类将会用来配置ContextLoaderListener建立的应用上下文中的bean
 @Override protected Class<?>[] getRootConfigClasses() { return new Class<?>[] {RootConfig.class}; } @Override protected Class<?>[] getServletConfigClasses() { return new Class<?>[] {ServletConfig.class}; } @Override protected void customizeRegistration(ServletRegistration.Dynamic registration) { // 上传文件的临时目录 String location = "/tmp"; // 上传文件的最大容量 long maxFileSize = 3145728; // 请求的最大容量 long maxRequestSize = 3145728; // 上传的最小临界值，大于该值才会被写入文件保存 // int fileSizeThreshold = 0; try { Properties prop = new Properties(); prop.load(Thread.currentThread().getContextClassLoader().getResourceAsStream("upload.properties")); location = prop.getProperty("temporary.location"); maxFileSize = Long.parseLong(prop.getProperty("max.file.size")); maxRequestSize = Long.parseLong(prop.getProperty("max.request.size")); } catch (IOException e) {} // 文件上传配置 registration.setMultipartConfig(new MultipartConfigElement(location, maxFileSize, maxRequestSize, 0)); // 没有找处处理的请求抛出异常 boolean done = registration.setInitParameter("throwExceptionIfNoHandlerFound", "true"); if(!done) throw new RuntimeException("设置异常(throwExceptionIfNoHandlerFound)"); } }

xml-base方式app

<bean id="multipartResolver" class="org.springframework.web.multipart.support.StandardServletMultipartResolver"></bean>

web.xml配置DispatcherServlet初始化参数ide

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd" id="WebApp_ID" version="3.0"> ...省略... <servlet>
        <servlet-name>dispatcher</servlet-name>
        <servlet-class>org.springframework.web.servlet.DispatcherServlet </servlet-class>
        <init-param>  
            <param-name>contextConfigLocation</param-name>  
            <param-value>classpath:dispatcher-servlet.xml</param-value>  
        </init-param>  
        <load-on-startup>0</load-on-startup>
        <multipart-config>
            <!--临时文件的目录-->
            <location>E:/tmp</location>
            <!-- 上传文件最大3M -->
            <max-file-size>3145728</max-file-size>
            <!-- 上传文件整个请求不超过3M -->
            <max-request-size>3145728</max-request-size>
        </multipart-config>
    </servlet> ...省略... </web-app>

Html代码

<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Insert title here</title>
</head>
<body>
<form action="/mvc/upload" enctype="multipart/form-data" method="post">
  <input name="fileData" type="file">
  <input type="submit" value="上传">
</form>
</body>
</html>

一、控制器接受文件原始byte[]。这种方式不可取，虽然能保存文件，可是咱们不知道文件原始名称，也不知道文件类型。

@RequestMapping("/upload") public Map<String, String> upload(@RequestPart("fileData") byte[] fileData) throws Exception { SimpleDateFormat format = new SimpleDateFormat("yyyyMMddHHssmm"); if (fileData != null) { FileOutputStream out = new FileOutputStream(new File("F:\\war\\" + format.format(new Date()))); out.write(fileData); out.close(); } Map<String, String> data = new HashMap<String, String>(); data.put("status", "ok"); return data; }

二、控制器接受MultipartFile类型

Multipart接口

public interface MultipartFile extends InputStreamSource { String getName();//参数名字
    String getOriginalFilename();//原始文件名
    String getContentType();//类型
    boolean isEmpty();//文件是否空
    long getSize();//文件字节大小
    byte[] getBytes() throws IOException;//返回字节数组
 @Override InputStream getInputStream() throws IOException;//输入流
    void transferTo(File dest) throws IOException, IllegalStateException;//转换文件
}

控制器代码

@RequestMapping("/upload") public Map<String, String> upload(MultipartFile fileData) throws Exception { if (fileData != null) { SimpleDateFormat format = new SimpleDateFormat("yyyyMMddHHssmm"); fileData.transferTo(new File("F:\\war\\" + format.format(new Date()) + "_" + fileData.getOriginalFilename()));//保存文件 } Map<String, String> data = new HashMap<String, String>(); data.put("status", "ok"); return data; }

三、控制器接受Part类型

Part接口

public interface Part { public InputStream getInputStream() throws IOException;//输入流
    public String getContentType();//类型
    public String getName();//参数名
    public String getSubmittedFileName();//原始文件名
    public long getSize();//字节大小
    public void write(String fileName) throws IOException;//保存文件
    public void delete() throws IOException;//删除文件
    public String getHeader(String name);//获取头信息
    public Collection<String> getHeaders(String name);//获取头信息
    public Collection<String> getHeaderNames();//获取头信息
}

控制器代码

@RequestMapping("/upload") public Map<String, String> upload(@RequestPart("fileData") Part fileData) throws Exception { if (fileData != null) { SimpleDateFormat format = new SimpleDateFormat("yyyyMMddHHssmm"); fileData.write("F:\\war\\" + format.format(new Date()) + "_" + fileData.getSubmittedFileName());//保存文件 } Map<String, String> data = new HashMap<String, String>(); data.put("status", "ok"); return data; }

方式2、使用CommonsMultipartResolver

依赖 commons-fileupload.jar 和 commons-io.jar。上传临时路径，文件大小都在对象中设置。

code-base方式

@Bean public MultipartResolver multipartResolver() throws IOException { CommonsMultipartResolver multipartResolver = new CommonsMultipartResolver(); multipartResolver.setUploadTempDir(new FileSystemResource(config.uploadTemporaryLocation())); multipartResolver.setMaxUploadSize(config.uploadMaxFileSize()); multipartResolver.setMaxInMemorySize(0); return multipartResolver; }

xml-base方式

<!-- 上传文件 -->  
<bean id="multipartResolver" class="org.springframework.web.multipart.commons.CommonsMultipartResolver">
    <property name="defaultEncoding" value="utf-8"/>
    <!-- 最大内存大小 -->
    <property name="maxInMemorySize" value="10240"/>
    <!-- 最大文件大小，-1为不限制大小 -->
    <property name="maxUploadSize" value="-1"/>
</bean>

示例代码：

实现了核心部分仅供参考。

package cn.ycx.web.controller; import java.io.File; import java.io.IOException; import java.text.SimpleDateFormat; import java.util.Date; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.stereotype.Controller; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.RequestMethod; import org.springframework.web.bind.annotation.RequestParam; import org.springframework.web.bind.annotation.ResponseBody; import org.springframework.web.multipart.MultipartFile; import cn.ycx.web.config.PropertyConfig; /** * 上传 * @author 杨崇兴 2018-07-09 */ @Controller @RequestMapping("/upload") public class UploadController extends BaseController { /** * 属性配置 */ @Autowired private PropertyConfig config; @RequestMapping(value="/image", method=RequestMethod.POST, produces="application/json;charset=UTF-8") public String image(@RequestParam(value = "imageFile", required = false) MultipartFile multipartFile) { try { String serverPath = config.uploadImageSavePath() + new SimpleDateFormat("yyyy/MM/dd/").format(new Date()); File serverPathFile = new File(serverPath); //目录不存在则建立
            if (!serverPathFile.exists()) { serverPathFile.mkdirs(); } String fileName = multipartFile.getOriginalFilename(); multipartFile.transferTo(new File(serverPath + fileName)); } catch (IllegalStateException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); } return "success"; } }

<!DOCTYPE html>
<html lang="zh" xmlns:th="http://www.thymeleaf.org">
    <head>
        <meta charset="UTF-8">
        <title>上传</title>
    </head>
<body>
<form action="/ycxcode/upload/image" method="post" enctype="multipart/form-data">
    <input type="text" name="discription" value="discription"/>
    <input type="file" name="imageFile">
    <input type="submit" value="submit"/>
</form>
</body>
</html>