上一篇博文讲到了（Servlet3.0支持）的文件上传：https://blog.csdn.net/frozenpower/article/details/81141297
这篇我们来看可配置的文件上传解析器CommonsMultipartResolver
CommonsMultipartResolver也实现了MultipartResolver。那我们看它的关键两个函数isMultipart和resolveMultipart
public boolean isMultipart(HttpServletRequest request) {
return ServletFileUpload.isMultipartContent(request);
}
public MultipartHttpServletRequest resolveMultipart(final HttpServletRequest request) throws MultipartException {
Assert.notNull(request, "Request must not be null");
if (this.resolveLazily) {
return new DefaultMultipartHttpServletRequest(request) {
protected void initializeMultipart() {
MultipartParsingResult parsingResult = CommonsMultipartResolver.this.parseRequest(request);
this.setMultipartFiles(parsingResult.getMultipartFiles());
this.setMultipartParameters(parsingResult.getMultipartParameters());
this.setMultipartParameterContentTypes(parsingResult.getMultipartParameterContentTypes());
}
};
} else {
MultipartParsingResult parsingResult = this.parseRequest(request);
return new DefaultMultipartHttpServletRequest(request, parsingResult.getMultipartFiles(), parsingResult.getMultipartParameters(), parsingResult.getMultipartParameterContentTypes());
}
}
protected MultipartParsingResult parseRequest(HttpServletRequest request) throws MultipartException {
String encoding = this.determineEncoding(request);
FileUpload fileUpload = this.prepareFileUpload(encoding);
try {
List<FileItem> fileItems = ((ServletFileUpload)fileUpload).parseRequest(request);
return this.parseFileItems(fileItems, encoding);
} catch (SizeLimitExceededException var5) {
throw new MaxUploadSizeExceededException(fileUpload.getSizeMax(), var5);
} catch (FileSizeLimitExceededException var6) {
throw new MaxUploadSizeExceededException(fileUpload.getFileSizeMax(), var6);
} catch (FileUploadException var7) {
throw new MultipartException("Failed to parse multipart servlet request", var7);
}
}
逻辑也不难
在使用的时候，首先要添加相关jar
<dependency>
<groupId>commons-io</groupId>
<artifactId>commons-io</artifactId>
<version>1.4</version>
</dependency>
<dependency>
<groupId>commons-fileupload</groupId>
<artifactId>commons-fileupload</artifactId>
<version>1.2.2</version>
</dependency>
配置multipartResolver解析器，替换原来默认的
<!-- 定义文件上传解析器 -->
<bean id="multipartResolver" class="org.springframework.web.multipart.commons.CommonsMultipartResolver">
<!-- 设定默认编码 -->
<property name="defaultEncoding" value="UTF-8"></property>
<!-- 设定文件上传的最大值为5MB，5*1024*1024 -->
<property name="maxUploadSize" value="5242880"></property>
<!-- 设定文件上传时写入内存的最大值，如果小于这个参数不会生成临时文件，默认为10240 -->
<property name="maxInMemorySize" value="40960"></property>
<!-- 上传文件的临时路径 -->
<property name="uploadTempDir" value="fileUpload/temp"></property>
<!-- 延迟文件解析 -->
<property name="resolveLazily" value="true"/>
</bean>
这两天发现了一个坑，还需要配置个转换器
@Configuration
@EnableWebMvc
public class MVCConfiguration extends WebMvcConfigurerAdapter {
@Override
public void configureMessageConverters(List<HttpMessageConverter<?>> converters) {
super.configureMessageConverters(converters);
// 初始化转换器
FastJsonHttpMessageConverter fastConvert = new FastJsonHttpMessageConverter();
// 初始化一个转换器配置
FastJsonConfig fastJsonConfig = new FastJsonConfig();
fastJsonConfig.setSerializerFeatures(SerializerFeature.PrettyFormat);
// 将配置设置给转换器并添加到HttpMessageConverter转换器列表中
fastConvert.setFastJsonConfig(fastJsonConfig);
List<MediaType> supportedMediaTypes = new ArrayList<>();
supportedMediaTypes.add(MediaType.APPLICATION_JSON_UTF8);
fastConvert.setSupportedMediaTypes(supportedMediaTypes);
converters.add(fastConvert);
}
}
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作者：frozenpower
来源：CSDN
原文：https://blog.csdn.net/frozenpower/article/details/81142034
版权声明：本文为博主原创文章，转载请附上博文链接！