【Java Web开发学习】Spring MVC文件上传
转载：https://www.cnblogs.com/yangchongxing/p/9290489.html
文件上传有两种实现方式，都比较简单
方式一、使用StandardServletMultipartResolver
依赖Servlet3.0对Multipart请求的支持，需要MultipartConfigElement配置请求的相关参数
Java配置方式
@Bean
public MultipartResolver multipartResolver() {
return new StandardServletMultipartResolver();
}
在Servlet中指定multipart配置，通过MultipartConfigElement设置上传临时路径，上传文件大小，上传请求的大小。
通过重载protected void customizeRegistration(ServletRegistration.Dynamic registration)方法实现，看代码
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创建的应用上下文中的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));
// 没有找到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
<bean id="multipartResolver" class="org.springframework.web.multipart.support.StandardServletMultipartResolver"></bean>
web.xml配置DispatcherServlet初始化参数
<?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>
1、控制器接受文件原始byte[]。这种方式不可取，虽然能保存文件，但是我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;
}2、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;
}3、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;
}方式二、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);
//目录不存在则创建
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>