org.springframework.biz.web.multipart.commons.MultipartStatusResolver Maven / Gradle / Ivy
package org.springframework.biz.web.multipart.commons;
import java.util.List;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpSession;
import org.apache.commons.fileupload.FileItem;
import org.apache.commons.fileupload.FileUpload;
import org.apache.commons.fileupload.FileUploadBase;
import org.apache.commons.fileupload.FileUploadException;
import org.apache.commons.fileupload.ProgressListener;
import org.apache.commons.fileupload.servlet.ServletFileUpload;
import org.springframework.web.multipart.MaxUploadSizeExceededException;
import org.springframework.web.multipart.MultipartException;
import org.springframework.web.multipart.commons.CommonsMultipartResolver;
/**
*
* Spring中带进度条的文件上传
* 1、Spring的DispatcherServlet在初始化的时候会去容器中查找是否有可用的MultipartResolver，如果有的话就会使用此resolver将request转换为MultipartHttpServletRequest。
* 2、Spring提供了两个resolver，CommonsMultipartResolver，StandardServletMultipartResolver。我们可以任选其一。
* CommonsMultipartResolver的parseRequest方法调用commons-fileupload的ServletFileupload完成了对request的解析工作。
* 3、最后在controller的配置文件中指定resolver： <bean id="multipartResolver" class="org.springframework.biz.web.multipart.commons.MultipartStatusResolver"></bean>
*/
public class MultipartStatusResolver extends CommonsMultipartResolver {
@Override
public MultipartParsingResult parseRequest(HttpServletRequest request) throws MultipartException {
String encoding = "utf-8";
FileUpload fileUpload = super.prepareFileUpload(encoding);
final HttpSession session = request.getSession();
fileUpload.setProgressListener(new ProgressListener() {
public void update(long pBytesRead, long pContentLength, int pItems) {
int percent = (int) (((float)pBytesRead / (float)pContentLength) * 100);
session.setAttribute("percent", percent + "%");
}
});
try {
List fileItems = ((ServletFileUpload) fileUpload).parseRequest(request);
return super.parseFileItems(fileItems, encoding);
}
catch (FileUploadBase.SizeLimitExceededException ex) {
throw new MaxUploadSizeExceededException(fileUpload.getSizeMax(), ex);
}
catch (FileUploadException ex) {
throw new MultipartException("Could not parse multipart servlet request", ex);
}
}
}