struts2上传文件显示进度条实例---有图有代码，一看就会

啰嗦两句：显示进度条其实没那么困难

有时候，不知道是环境问题还是人品问题，遇到的bug总是莫名其妙的。可是说到底还是某个知识点不太熟练。这次吐槽一下前端jquery的submit方法。下午的时候测试提交能顺利完成任务，可是到了十一点多的时候就不行了。我知道，程序员十大谎言之一就是：我真的没改这部分代码。好吧，既然不太清除bug到底是怎么出现的，那么就换一种提交方法吧。
所以直接把button类型改成submit，再设置它的click事件，让表单自己提交好了。知识点的盲区就在这时候出现了。由于要轮询后台文件的上传进度信息，不得不一边提交file一遍ajax获取进度。实在是不太清楚setinterval这个方法是异步还是同步，会不会阻塞submit（又和上一段中提到的文件submit不成功混在一起，就测试了好久）。在这个地方也停留了好久。。。
最后，项目还残存的问题就是：明明是每隔500ms向后台请求的进度信息，但是实际上后台并不能够在这段时间内返回对应的信息。亟待优化！
效果图如下：

获取文件上传信息的基本步骤：经测试有效

上传文件时如何获取上传进度信息？

从网上查一下资料就可以知道struts2对文件上传的request请求做了封装，也就是说在调用上传文件的action时就已经上传temp完成了。
那么既然这样，我们就可以重写struts2封装request的类：org.apache.struts2.dispatcher.multipart.JakartaMultiPartRequest;
由于这个类的许多方法都是private的，那么也就是说我们是无法通过extends来重写父类的一些方法的。怎么办呢？
暴力一点！
直接自定义一个JakartaMultiPartRequest类型的类，把父类的方法全部copy过来，然后在struts.xml中配置：

<struts>    <bean type="org.apache.struts2.dispatcher.multipart.MultiPartRequest"          name="myRequestParser" class="listener.MultiPartRequest"          scope="default" optional="true" />    <!-- 注意struts2.3.15.1以前版本这里为struts.multipart.handler， struts2.3.15.1（包含2.3.15.1）这里为struts.multipart.parser-->    <constant name="struts.multipart.handler" value="myRequestParser"/>    <!--action-->    ....    </struts>

接下来我们实现上述配置文件中的MultiPartRequest类：
通过intellij的反编译插件，我们decode JakartaMultiPartRequest这个类：源码如下—-大量代码来袭，直接copy这部分吧 不用细看

/* * $Id: JakartaMultiPartRequest.java 1384107 2012-09-12 20:14:23Z lukaszlenart $ * * Licensed to the Apache Software Foundation (ASF) under one * or more contributor license agreements.  See the NOTICE file * distributed with this work for additional information * regarding copyright ownership.  The ASF licenses this file * to you under the Apache License, Version 2.0 (the * "License"); you may not use this file except in compliance * with the License.  You may obtain a copy of the License at * *  http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, * software distributed under the License is distributed on an * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY * KIND, either express or implied.  See the License for the * specific language governing permissions and limitations * under the License. */package org.apache.struts2.dispatcher.multipart;import com.opensymphony.xwork2.LocaleProvider;import com.opensymphony.xwork2.inject.Inject;import com.opensymphony.xwork2.util.LocalizedTextUtil;import com.opensymphony.xwork2.util.logging.Logger;import com.opensymphony.xwork2.util.logging.LoggerFactory;import org.apache.commons.fileupload.FileItem;import org.apache.commons.fileupload.FileUploadBase;import org.apache.commons.fileupload.FileUploadException;import org.apache.commons.fileupload.RequestContext;import org.apache.commons.fileupload.disk.DiskFileItem;import org.apache.commons.fileupload.disk.DiskFileItemFactory;import org.apache.commons.fileupload.servlet.ServletFileUpload;import org.apache.struts2.StrutsConstants;import javax.servlet.http.HttpServletRequest;import java.io.File;import java.io.IOException;import java.io.InputStream;import java.io.UnsupportedEncodingException;import java.util.ArrayList;import java.util.Collections;import java.util.Enumeration;import java.util.HashMap;import java.util.List;import java.util.Locale;import java.util.Map;import java.util.Set;/** * Multipart form data request adapter for Jakarta Commons Fileupload package. */public class JakartaMultiPartRequest implements MultiPartRequest {    static final Logger LOG = LoggerFactory.getLogger(JakartaMultiPartRequest.class);    // maps parameter name -> List of FileItem objects    protected Map<String, List<FileItem>> files = new HashMap<String, List<FileItem>>();    // maps parameter name -> List of param values    protected Map<String, List<String>> params = new HashMap<String, List<String>>();    // any errors while processing this request    protected List<String> errors = new ArrayList<String>();    protected long maxSize;    private Locale defaultLocale = Locale.ENGLISH;    @Inject(StrutsConstants.STRUTS_MULTIPART_MAXSIZE)    public void setMaxSize(String maxSize) {        this.maxSize = Long.parseLong(maxSize);    }    @Inject    public void setLocaleProvider(LocaleProvider provider) {        defaultLocale = provider.getLocale();    }    /**     * Creates a new request wrapper to handle multi-part data using methods adapted from Jason Pell's     * multipart classes (see class description).     *     * @param saveDir the directory to save off the file     * @param request the request containing the multipart     * @throws java.io.IOException is thrown if encoding fails.     */    public void parse(HttpServletRequest request, String saveDir) throws IOException {        try {            setLocale(request);            processUpload(request, saveDir);        } catch (FileUploadBase.SizeLimitExceededException e) {            if (LOG.isWarnEnabled()) {                LOG.warn("Request exceeded size limit!", e);            }            String errorMessage = buildErrorMessage(e, new Object[]{e.getPermittedSize(), e.getActualSize()});            if (!errors.contains(errorMessage)) {                errors.add(errorMessage);            }        } catch (Exception e) {            if (LOG.isWarnEnabled()) {                LOG.warn("Unable to parse request", e);            }            String errorMessage = buildErrorMessage(e, new Object[]{});            if (!errors.contains(errorMessage)) {                errors.add(errorMessage);            }        }    }    protected void setLocale(HttpServletRequest request) {        if (defaultLocale == null) {            defaultLocale = request.getLocale();        }    }    protected String buildErrorMessage(Throwable e, Object[] args) {        String errorKey = "struts.messages.upload.error." + e.getClass().getSimpleName();        if (LOG.isDebugEnabled()) {            LOG.debug("Preparing error message for key: [#0]", errorKey);        }        return LocalizedTextUtil.findText(this.getClass(), errorKey, defaultLocale, e.getMessage(), args);    }    private void processUpload(HttpServletRequest request, String saveDir) throws FileUploadException, UnsupportedEncodingException {        for (FileItem item : parseRequest(request, saveDir)) {            if (LOG.isDebugEnabled()) {                LOG.debug("Found item " + item.getFieldName());            }            if (item.isFormField()) {                processNormalFormField(item, request.getCharacterEncoding());            } else {                processFileField(item);            }        }    }    private void processFileField(FileItem item) {        if (LOG.isDebugEnabled()) {            LOG.debug("Item is a file upload");        }        // Skip file uploads that don't have a file name - meaning that no file was selected.        if (item.getName() == null || item.getName().trim().length() < 1) {            LOG.debug("No file has been uploaded for the field: " + item.getFieldName());            return;        }        List<FileItem> values;        if (files.get(item.getFieldName()) != null) {            values = files.get(item.getFieldName());        } else {            values = new ArrayList<FileItem>();        }        values.add(item);        files.put(item.getFieldName(), values);    }    private void processNormalFormField(FileItem item, String charset) throws UnsupportedEncodingException {        if (LOG.isDebugEnabled()) {            LOG.debug("Item is a normal form field");        }        List<String> values;        if (params.get(item.getFieldName()) != null) {            values = params.get(item.getFieldName());        } else {            values = new ArrayList<String>();        }        // note: see http://jira.opensymphony.com/browse/WW-633        // basically, in some cases the charset may be null, so        // we're just going to try to "other" method (no idea if this        // will work)        if (charset != null) {            values.add(item.getString(charset));        } else {            values.add(item.getString());        }        params.put(item.getFieldName(), values);        item.delete();    }    private List<FileItem> parseRequest(HttpServletRequest servletRequest, String saveDir) throws FileUploadException {        DiskFileItemFactory fac = createDiskFileItemFactory(saveDir);        ServletFileUpload upload = new ServletFileUpload(fac);        upload.setSizeMax(maxSize);        return upload.parseRequest(createRequestContext(servletRequest));    }    private DiskFileItemFactory createDiskFileItemFactory(String saveDir) {        DiskFileItemFactory fac = new DiskFileItemFactory();        // Make sure that the data is written to file        fac.setSizeThreshold(0);        if (saveDir != null) {            fac.setRepository(new File(saveDir));        }        return fac;    }    /* (non-Javadoc)     * @see org.apache.struts2.dispatcher.multipart.MultiPartRequest#getFileParameterNames()     */    public Enumeration<String> getFileParameterNames() {        return Collections.enumeration(files.keySet());    }    /* (non-Javadoc)     * @see org.apache.struts2.dispatcher.multipart.MultiPartRequest#getContentType(java.lang.String)     */    public String[] getContentType(String fieldName) {        List<FileItem> items = files.get(fieldName);        if (items == null) {            return null;        }        List<String> contentTypes = new ArrayList<String>(items.size());        for (FileItem fileItem : items) {            contentTypes.add(fileItem.getContentType());        }        return contentTypes.toArray(new String[contentTypes.size()]);    }    /* (non-Javadoc)     * @see org.apache.struts2.dispatcher.multipart.MultiPartRequest#getFile(java.lang.String)     */    public File[] getFile(String fieldName) {        List<FileItem> items = files.get(fieldName);        if (items == null) {            return null;        }        List<File> fileList = new ArrayList<File>(items.size());        for (FileItem fileItem : items) {            File storeLocation = ((DiskFileItem) fileItem).getStoreLocation();            if (fileItem.isInMemory() && storeLocation != null && !storeLocation.exists()) {                try {                    storeLocation.createNewFile();                } catch (IOException e) {                    if (LOG.isErrorEnabled()) {                        LOG.error("Cannot write uploaded empty file to disk: " + storeLocation.getAbsolutePath(), e);                    }                }            }            fileList.add(storeLocation);        }        return fileList.toArray(new File[fileList.size()]);    }    /* (non-Javadoc)     * @see org.apache.struts2.dispatcher.multipart.MultiPartRequest#getFileNames(java.lang.String)     */    public String[] getFileNames(String fieldName) {        List<FileItem> items = files.get(fieldName);        if (items == null) {            return null;        }        List<String> fileNames = new ArrayList<String>(items.size());        for (FileItem fileItem : items) {            fileNames.add(getCanonicalName(fileItem.getName()));        }        return fileNames.toArray(new String[fileNames.size()]);    }    /* (non-Javadoc)     * @see org.apache.struts2.dispatcher.multipart.MultiPartRequest#getFilesystemName(java.lang.String)     */    public String[] getFilesystemName(String fieldName) {        List<FileItem> items = files.get(fieldName);        if (items == null) {            return null;        }        List<String> fileNames = new ArrayList<String>(items.size());        for (FileItem fileItem : items) {            fileNames.add(((DiskFileItem) fileItem).getStoreLocation().getName());        }        return fileNames.toArray(new String[fileNames.size()]);    }    /* (non-Javadoc)     * @see org.apache.struts2.dispatcher.multipart.MultiPartRequest#getParameter(java.lang.String)     */    public String getParameter(String name) {        List<String> v = params.get(name);        if (v != null && v.size() > 0) {            return v.get(0);        }        return null;    }    /* (non-Javadoc)     * @see org.apache.struts2.dispatcher.multipart.MultiPartRequest#getParameterNames()     */    public Enumeration<String> getParameterNames() {        return Collections.enumeration(params.keySet());    }    /* (non-Javadoc)     * @see org.apache.struts2.dispatcher.multipart.MultiPartRequest#getParameterValues(java.lang.String)     */    public String[] getParameterValues(String name) {        List<String> v = params.get(name);        if (v != null && v.size() > 0) {            return v.toArray(new String[v.size()]);        }        return null;    }    /* (non-Javadoc)     * @see org.apache.struts2.dispatcher.multipart.MultiPartRequest#getErrors()     */    public List<String> getErrors() {        return errors;    }    /**     * Returns the canonical name of the given file.     *     * @param filename the given file     * @return the canonical name of the given file     */    private String getCanonicalName(String filename) {        int forwardSlash = filename.lastIndexOf("/");        int backwardSlash = filename.lastIndexOf("\\");        if (forwardSlash != -1 && forwardSlash > backwardSlash) {            filename = filename.substring(forwardSlash + 1, filename.length());        } else if (backwardSlash != -1 && backwardSlash >= forwardSlash) {            filename = filename.substring(backwardSlash + 1, filename.length());        }        return filename;    }    /**     * Creates a RequestContext needed by Jakarta Commons Upload.     *     * @param req the request.     * @return a new request context.     */    private RequestContext createRequestContext(final HttpServletRequest req) {        return new RequestContext() {            public String getCharacterEncoding() {                return req.getCharacterEncoding();            }            public String getContentType() {                return req.getContentType();            }            public int getContentLength() {                return req.getContentLength();            }            public InputStream getInputStream() throws IOException {                InputStream in = req.getInputStream();                if (in == null) {                    throw new IOException("Missing content in the request");                }                return req.getInputStream();            }        };    }    /* (non-Javadoc)    * @see org.apache.struts2.dispatcher.multipart.MultiPartRequest#cleanUp()    */    public void cleanUp() {        Set<String> names = files.keySet();        for (String name : names) {            List<FileItem> items = files.get(name);            for (FileItem item : items) {                if (LOG.isDebugEnabled()) {                    String msg = LocalizedTextUtil.findText(this.getClass(), "struts.messages.removing.file",                            Locale.ENGLISH, "no.message.found", new Object[]{name, item});                    LOG.debug(msg);                }                if (!item.isInMemory()) {                    item.delete();                }            }        }    }}

好的，我们把上面这部分代码copy到我们自定义的public class MultiPartRequest extends JakartaMultiPartRequest {}中
复制粘贴完了之后，我们要ctrl f找到parseRequest方法。在这里，我们要设置文件上传进度监听器

  /**     * 自定义的parseRequest方法     * @param servletRequest     * @param saveDir     * @return     * @throws FileUploadException     */    private List<FileItem> parseRequest(HttpServletRequest servletRequest, String saveDir) throws FileUploadException {        System.out.println("调用parseRequest方法");        UploadProgressListener listener = new UploadProgressListener(servletRequest);        DiskFileItemFactory fac = createDiskFileItemFactory(saveDir);        ServletFileUpload upload = new ServletFileUpload(fac);        upload.setSizeMax(maxSize);        upload.setProgressListener(listener);        System.out.println("设置监听器成功");        return upload.parseRequest(createRequestContext(servletRequest));    }

在上面这个代码片段中可以看到：我们new了一个监听器UploadProgressListener 的实例，然后调用了ServletFileUpload .setProgressListener（listener）方法。也就是说：这里的监听器与我们以前写过的request,session等等监听器不同，不需要在web.xml中配置。这里只需要一行代码即可解决。

那么我们就来实现这个监听器吧！

这个监听器需要实org.apache.commons.fileupload.ProgressListener这个接口：我们直接implement一下。
在update方法中我们可以获取到已上传的文件长度，上传的文件的总长度，当前上传第几个文件。（当你上传一个文件的时候，打印日志就会发现这里会输出2。个人猜测是先上传到temp然后再上传到指定路径…）
我们在update方法中设置了文件上传状态实体类的实例，并且保存到session。这一步就是能让前端使用ajax访问到文件当前的上传进度信息。

package listener;import entity.FileUploadProgress;import org.apache.commons.fileupload.ProgressListener;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpSession;/** * Created by zipple on 2017/10/13. * 监听文件上传情况 * 实现org.apache.commons.fileupload.ProgressListener接口 */public class UploadProgressListener implements ProgressListener {    private HttpSession session;//创建监听器实例的时候获取session    //在自定义的MultiPartRequest 类中 创建此监听器的实例    public UploadProgressListener(HttpServletRequest request) {        session = request.getSession();        FileUploadProgress fileUploadProgress = new FileUploadProgress();        fileUploadProgress.setFlag(false);        session.setAttribute("fileUploadProgress", fileUploadProgress);    }    @Override    public void update(long readBytes, long totalBytes, int currentItem) {        //实现文件上传的核心方法        Object attribute = session.getAttribute("fileUploadProgress");//        System.out.println("当前已读取:"+readBytes+" 总长度:"+totalBytes+" 正在保存:"+currentItem);        FileUploadProgress fileUploadProgress;        if(null == attribute){            fileUploadProgress = new FileUploadProgress();            fileUploadProgress.setFlag(false);            System.out.println("uploadListener文件上传的开始时间："+fileUploadProgress.getStartTime());            session.setAttribute("fileUploadProgress", fileUploadProgress);        }else{            fileUploadProgress = (FileUploadProgress)attribute;        }        fileUploadProgress.setCurrentLength(readBytes);        fileUploadProgress.setTotalLength(totalBytes);        if(readBytes==totalBytes){            fileUploadProgress.setFlag(true);        }else{            fileUploadProgress.setFlag(false);        }        session.setAttribute("fileUploadProgress", fileUploadProgress);    }}

文件上传状态实体类代码：

package entity;/** * Created by zipple on 2017/10/14. * 上传文件进度信息实体类 */public class FileUploadProgress {    private long startTime = System.currentTimeMillis();//开始时间    private long totalLength=1;//文件上传的总长度    private long currentLength=0;//当前文件上传的长度    private boolean flag;//是否上传完成    public long getTotalLength() {        return totalLength;    }    public void setTotalLength(long totalLength) {        this.totalLength = totalLength;    }    public long getCurrentLength() {        return currentLength;    }    public void setCurrentLength(long currentLength) {        this.currentLength = currentLength;    }    public boolean isFlag() {        return flag;    }    public void setFlag(boolean flag) {        this.flag = flag;    }    public long getStartTime() {        return startTime;    }    public void setStartTime(long startTime) {        this.startTime = startTime;    }    public FileUploadProgress(){        super();    }}

前端获取后台文件上传的进度信息

好的，前面已经做完了所有的基本工作了。万事俱备，我们最后只需要实现对应的查询action即可。在这个地方我也要记录一个bug。在使用ajax访问这个action的时候，一直报错。当然，我在前面的博客中也吐槽过了，这个报错信息一点用没有。我又找了好久。后来发现jsonData只是单纯的定义了map对象，并没有new出它的实例，所以空指针异常了！！！
这里我们使用的是返回json数据。（需要struts2-json-plugin-2.3.16.jar）

package action;import com.opensymphony.xwork2.Action;import entity.FileUploadProgress;import org.apache.struts2.ServletActionContext;import util.DataUtil;import java.util.HashMap;import java.util.Map;/** * Created by zipple on 2017/10/15. * 获取文件进度信息 */public class ProgressAction implements Action {    private Map<String,Object> jsonData;    @Override    public String execute() throws Exception {        System.out.println("获取上传文件进度信息");        jsonData = new HashMap<>();//初始化jsonData!!!!        FileUploadProgress p;        Object attribute = ServletActionContext.getRequest().getSession().getAttribute("fileUploadProgress");        if(null == attribute){            System.out.println("session中没有fileupload信息");            jsonData.put("completed", false);            jsonData.put("isStarted", false);            setJsonData(jsonData);            return SUCCESS;        }else{            System.out.println("session中有fileupload信息");            p = (FileUploadProgress)attribute;        }        System.out.println("action中获取到的文件上传的开始时间："+p.getStartTime());        System.out.println("action运行到这里的时间:"+System.currentTimeMillis());        long time = (System.currentTimeMillis() - p.getStartTime())/ 1000 + 1; //已传输的时间 单位:s        System.out.println("截至目前上传时间："+time);        double v = ((double)p.getCurrentLength()) / (double)time; // b/s        System.out.println("传输速度："+v);        System.out.println("pAction:当前上传--"+p.getCurrentLength());        jsonData.put("percent", DataUtil.percent(p.getCurrentLength(),p.getTotalLength()));        jsonData.put("remain", (int)(p.getTotalLength()/v-time));        jsonData.put("isStarted", true);        jsonData.put("completed", p.isFlag());        if (p.isFlag()){            System.out.println("已完成，重置fileUploadProgress");            ServletActionContext.getRequest().getSession().removeAttribute("fileUploadProgress");        }        setJsonData(jsonData);        return SUCCESS;    }    public Map<String,Object> getJsonData() {        return jsonData;    }    public void setJsonData(Map<String,Object> jsonData) {        this.jsonData = jsonData;    }}

返回json数据的struts.xml配置如下:

 <package name="json" extends="struts-default,json-default">        <action name="getProgress" class="action.ProgressAction" method="execute">            <result name="success" type="json">                <param name="root">jsonData</param><!-- action中的要返回的属性 -->            </result>        </action>        </package>

项目做到这里，后端的事情已经做完了。接下来就是前端显示进度条的事情。需要的同学可以继续往下看咯。

前端那些事儿——css实现进度条控件

css:可以直接copy，无需细看（firefox下测试无问题）

.progress{    height: 20px;    background: #ebebeb;    border-left: 1px solid transparent;    border-right: 1px solid transparent;    border-radius: 10px;}.progress .blue {    background: #5aaadb;    border-color: #459fd6 #3094d2 #277db2;    background-image: -webkit-linear-gradient(top, #aed5ed 0%, #7bbbe2 70%, #5aaadb 100%);    background-image: -moz-linear-gradient(top, #aed5ed 0%, #7bbbe2 70%, #5aaadb 100%);    background-image: -o-linear-gradient(top, #aed5ed 0%, #7bbbe2 70%, #5aaadb 100%);    background-image: linear-gradient(to bottom, #aed5ed 0%, #7bbbe2 70%, #5aaadb 100%);}.progress > span {    position: relative;    float: left;    margin: 0 -1px;    min-width: 30px;    height: 18px;    line-height: 16px;    text-align: right;    background: #cccccc;    border: 1px solid;    border-color: #bfbfbf #b3b3b3 #9e9e9e;    border-radius: 10px;    background-image: -webkit-linear-gradient(top, #f0f0f0 0%, #dbdbdb 70%, #cccccc 100%);    background-image: -moz-linear-gradient(top, #f0f0f0 0%, #dbdbdb 70%, #cccccc 100%);    background-image: -o-linear-gradient(top, #f0f0f0 0%, #dbdbdb 70%, #cccccc 100%);    background-image: linear-gradient(to bottom, #f0f0f0 0%, #dbdbdb 70%, #cccccc 100%);    -webkit-box-shadow: inset 0 1px rgba(255, 255, 255, 0.3), 0 1px 2px rgba(0, 0, 0, 0.2);    box-shadow: inset 0 1px rgba(255, 255, 255, 0.3), 0 1px 2px rgba(0, 0, 0, 0.2);}.progress > span > span {    padding: 0 8px;    font-size: 11px;    font-weight: bold;    color: #404040;    color: rgba(0, 0, 0, 0.7);    text-shadow: 0 1px rgba(255, 255, 255, 0.4);}.progress > span:before {    content: '';    position: absolute;    top: 0;    bottom: 0;    left: 0;    right: 0;    z-index: 1;    height: 18px;    background: url("http://js.itivy.com/5-progress-bars/img/progress.png") 0 0 repeat-x;    border-radius: 10px;}

html调用progress代码很简单，就一行：这里设置隐藏，上传文件时再显示

      <div class="progress" style="width: 400px;" hidden="hidden"><span class="blue" style="width: 1%;"><span>1%</span></span></div>

控制进度条代码：在提交文件时同步调用此计时器即可。

setInterval(progressBar,500);    /**      * 展示上传进度条      */function progressBar () {         console.log("询问后台进度...");         $.ajax({             type : "GET",  //提交方式             url : "getProgress.action",//路径             success : function(result) {//返回数据根据结果进行相应的处理                 console.log(result);                 console.log("文件是否上传完成"+result.completed);                 if (result.isStarted){                     if (result.completed){                         $(".progress").hide();                         clearInterval(progressBar);//清除计时器                     }else{                         $(".progress >span").css({"width":result.percent});                         $(".progress >span>span").text(result.percent);                         $(".remain").text(result.remain);                     }                 }else{                     console.log("文件还没有提交");                 }             },             //异常处理             error:function (XMLHttpRequest, textStatus, errorThrown) {                 console.log(XMLHttpRequest+"---"+textStatus+"---"+errorThrown);             }         });      }

看到这里，上传文件显示进度条的相关内容基本上是结束了。
有问题的，可以留言交流~

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