基于restful api格式的文件上传(只是上传到本地):

package com.nxz.controller;

import com.nxz.entity.FileInfo;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.multipart.MultipartFile; import java.io.File;
import java.io.IOException;
import java.util.Date; @RestController
@RequestMapping("/file")
public class FileController {
@PostMapping
public FileInfo update(MultipartFile file) throws IOException { System.out.println(file.getName());
System.out.println(file.getOriginalFilename());
System.out.println(file.getSize()); String holder = "G:\\0001-myproject\\mysecurity\\mysecurity-demo\\src\\main\\java\\com\\nxz\\controller"; File localFile = new File(holder, new Date().getTime() + ".txt"); file.transferTo(localFile); return new FileInfo(localFile.getAbsolutePath());
} }

测试用例:

   //伪造的mvc环境
@Autowired
private WebApplicationContext webApplicationContext;
private MockMvc mockMvc;
@Before
public void before() {
mockMvc = MockMvcBuilders.webAppContextSetup(webApplicationContext).build();
}
@Test
public void whenUploadSuccess() throws Exception {
String file = mockMvc.perform(MockMvcRequestBuilders.fileUpload("/file")
.file(new MockMultipartFile("file", "test.txt", "multipart/form-data", "hello".getBytes("UTF-8"))))
.andExpect(MockMvcResultMatchers.status().isOk())
.andReturn().getResponse().getContentAsString();
System.out.println(file);
}

测试用例执行完之后输出文件绝对路径:

{"path":"G:\\mysecurity\\mysecurity-demo\\src\\main\\java\\com\\nxz\\controller\\1556463660034.txt"}

下载:

 @GetMapping("/{id}")
public void downLoad(@PathVariable String id,
HttpServletRequest request,
HttpServletResponse response) throws IOException {
String holder = "G:\\0001-myproject\\mysecurity\\mysecurity-demo\\src\\main\\java\\com\\nxz\\controller";
try (
InputStream inputStream = new FileInputStream(new File(holder, id + ".txt"));
OutputStream outputStream = response.getOutputStream();
) {
response.setContentType("application/x-download");
response.addHeader("Content-Disposition", "attachment;filename=test.txt");//重新定义下载后名称
//将文件输入流复制到输出刘超过年 commons-io依赖
IOUtils.copy(inputStream, outputStream);
outputStream.flush();
} }

访问:http://localhost:8080/user/1

restful api上传文件(基础)-springboot-LMLPHP

springboot中上传文件:

java中和文件上传的类又两个:CommonsMultipartResolver,另一个就是StandardServletMultipartResolver,其中commonsMultipartResolver需要commons-fileupload支持,二StandardServletMultipartReslover是servlet3.0默认支持的,tomcat7以上版本就开始支持servlet7.0,springboot22.0之后支持的tomcat版本在7之后,因此是支持StandardServletMultipartReslover的

首先 springboot只要配置好pom(有spring-boot-starter-web依赖),就能自动支持文件上传(包括单文件和多文件),那么springboot中文件上传是怎样起作用的

1、pom依赖,下边这些依赖中,和配置文件上传有关的就是spring-boot-autoconfig依赖

        <dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency> ---->>> <dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter</artifactId>
<version>2.1.3.RELEASE</version>
<scope>compile</scope>
</dependency> ---->>>> <dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-autoconfigure</artifactId>
<version>2.1.3.RELEASE</version>
<scope>compile</scope>
</dependency>

2、那么看下spring-boot-autoconfig jar包中的spring.factories文件中的内容,这个文件中全都是和springboot自动配置相关的类的全文件名,其中和文件上传有关的是

org.springframework.boot.autoconfigure.web.servlet.MultipartAutoConfiguration,\

3、进入这个类中(具体个各种autoconfiguration自动加载类是什么时候加载的,需要看springboot的启动来注解和启动类)

@Configuration
@ConditionalOnClass({ Servlet.class, StandardServletMultipartResolver.class,
MultipartConfigElement.class }) //这个注解表示存在servlet、StandardServletMultipartResolver、multipartConfigElement文件时才加载该类
@ConditionalOnProperty(prefix = "spring.servlet.multipart", name = "enabled", matchIfMissing = true)//配置文件的前缀
@ConditionalOnWebApplication(type = Type.SERVLET)//servlet
@EnableConfigurationProperties(MultipartProperties.class)//配置文件类
public class MultipartAutoConfiguration { private final MultipartProperties multipartProperties; public MultipartAutoConfiguration(MultipartProperties multipartProperties) {
this.multipartProperties = multipartProperties;
} @Bean
@ConditionalOnMissingBean({ MultipartConfigElement.class,
CommonsMultipartResolver.class })//当没有commonsMultipartResolver文件时,初始化该bean
public MultipartConfigElement multipartConfigElement() {
return this.multipartProperties.createMultipartConfig();
} @Bean(name = DispatcherServlet.MULTIPART_RESOLVER_BEAN_NAME)
@ConditionalOnMissingBean(MultipartResolver.class)
public StandardServletMultipartResolver multipartResolver() {
StandardServletMultipartResolver multipartResolver = new StandardServletMultipartResolver();//springboot默认的文件上传的类
multipartResolver.setResolveLazily(this.multipartProperties.isResolveLazily());
return multipartResolver;
} }
05-07 10:40
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