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使用Tomcat在Spring中上传文件与允许的最大大小有关

问题内容：

我对Spring相当陌生，我想拥有一个多部分表单并处理MaxUploadSizeExceededException异常，以便在jsp中显示错误消息。我遇到的主要问题是MaxUploadSizeLimitExceededExceptionResolver类中的ModelAndView对象，我不知道如何将其用于上述目的。

我拥有的文件：1）模型类UploadItem.java。2）查看表单UploadForm.jsp。3）控制器Uploadcontroller.java。4）类MaxUploadSizeLimitExceededExceptionResolver.java处理异常Uploadcontroller

1）模型UploadItem

public class UploadItem {
    private String name;
    private CommonsMultipartFile fileData;

    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
    public CommonsMultipartFile getFileData() {
        return fileData;
    }
    public void setFileData(CommonsMultipartFile fileData) {
        this.fileData = fileData;
    }
}

2）查看表单UploadForm.jsp

<html>
    <head>
        <META http-equiv="Content-Type" content="text/html;charset=UTF-8">
        <title>Upload form</title>
    </head>
    <body>
        <form:form modelAttribute="uploadItem" method="post" enctype="multipart/form-data">
            <fieldset>
                <legend>Upload Fields</legend>
                <p>
                    <form:label for="name" path="name">Name</form:label><br/>
                    <form:input path="name"/>
                </p>
                <p>
                    <form:label for="fileData" path="fileData">File</form:label><br/>
                    <form:input path="fileData" type="file"/>
                </p>
                <p>
                    <input type="submit" />
                </p>
            </fieldset>
        </form:form>
    </body>
</html>

3）控制器上传控制器

public class Uploadcontroller {
    @RequestMapping(method = RequestMethod.GET)
    public String getUploadForm(Model model) {
        model.addAttribute(new UploadItem());
        return "upload/uploadForm";
    }

    @RequestMapping(method = RequestMethod.POST)
    public String create(HttpServletRequest request, UploadItem uploadItem,
            BindingResult result, Exception exception) {
        if (result.hasErrors()) {
            // logger.info("create upload");
            for (ObjectError error : result.getAllErrors()) {
                System.err.println("Error: " + error.getCode() + " - "
                        + error.getDefaultMessage());
            }
            return "upload/uploadForm";
        }

        System.err.println("Test upload: " + uploadItem.getName());
        System.err.println("Test upload: "
                + uploadItem.getFileData().getOriginalFilename());

        // TODO redirect this
        return "/home";
    }
}

4）处理异常的组件Uploadcontroller

@Component
public class MaxUploadSizeLimitExceededExceptionResolver extends
        SimpleMappingExceptionResolver {
    private static final Logger logger = LoggerFactory
            .getLogger(HomeController.class);

    @Override
    public ModelAndView resolveException(HttpServletRequest request,
            HttpServletResponse response, Object handler, Exception exception) {
        Map<String, Object> model = new HashMap<String, Object>();
        logger.info("getUploadForm at the beggining");
        ModelAndView modelView = new ModelAndView();
        if (exception instanceof MaxUploadSizeExceededException)
        {
            model.put("errors", exception.getMessage());
            modelView.addObject("errors", exception.getMessage());
            logger.info("getUploadForm: MaxUploadSizeExceededException" );
        } else
        {
            model.put("errors", "Unexpected error: " + exception.getMessage());
            modelView.addObject("errors", "Unexpected error: " +exception.getMessage());
        }
        logger.info("getUploadForm at the end" );        
        model.put("uploadedFile", new UploadItem());
        modelView.addObject(new UploadItem());//("uploadedFile", new UploadItem());
        modelView.setViewName("/upload/uploadForm");
        return modelView;
    }
}

编辑以添加更多详细信息：实际上，问题出在另一个方向。我的maxUploadSize文件的大小设置为1MB，但是我试图对大于3
MB的文件进行测试。当我尝试使用一个文件直到最大2
MB正常工作时。问题是我得到了ERR_CONNECTION_RESET，似乎与Tomcat有关，它是maxSwallowSize的配置->stackoverflow.com/questions/29113262/…。我将继续研究并保持该线程更新。

新的消息。我尝试使用Tomcat 7.0.61，错误是ERR_CONNECTION_ABORTED我尝试使用Tomcat 6.0.43，没有错误！


问题答案：

经过调查，问题出在Tomcat。
在版本7.0.55中引入了属性maxSwallowSize，默认情况下将其设置为2MB。这使得Tomcat中止了上载请求。通过将此属性设置为另一个值，可以解决问题（我将其更改为-1，请不要在您的PRD环境中执行此操作，因为Tomcat确实会尝试获取要上传的X
MB文件）。为此，我在连接器属性的Tomcat服务器文件$ {tomcat_dir}
/conf/server.xml中添加了属性maxSwallowSize

<Connector port="8080" protocol="HTTP/1.1"
    connectionTimeout="20000"
    redirectPort="8443" 
    maxSwallowSize="-1"/>

您需要重新启动Tomcat，以便它采用此配置，如果不起作用，请删除服务器并再次添加。