webupload+servlet+fileupload实现文件的批量上传

先看结果图。上传前端页面：

上传后台显示：

上传图片文件夹：

图片的批量上传真的折磨了我一周。之所以对图片的批量上传这么执着是因为我之前自己做的几个项目都用到了图片上传，时光邮寄就只是单张图片上传，而个人云相册用到了批量上传，之前用的那个框架我觉得不美观，而且我只是把框架用来复用，并没有好好研究，所以说起来还是算不会。而上周做公司的项目的时候，也碰到了图片上传。所以我觉得图片上传功能的实现还是挺有必要的，尤其是图片的批量上传。

于是百度，我发现了webupload这个前端框架，感觉还是挺美观的。而且可以直接用，简单改一下upload.js里的图片上传处理server就行，可以简单上手。

于是，上周就开始了图片批量上传的研究，不，现在还应该说是这周，毕竟星期天还没结束。但是实现过程中，真的是碰到了一系列问题，电脑卡死，缓存，刷新不了，idea惹我，哎，用idea部署，它老是不加载更新的js文件，导致我以为我改错upload.js的路径了，而且当时我的请求方式为option，但是我改了请求方式的为post，我真的是被弄的晕头转向，导致想放弃。今天和小何去逛了锦里，然后聊了一下午的天，谈起长大后的很多迫不得已，谈起更好的生活，谈起奋斗，哈哈哈，夸张了。今天很热，我们在商场吹了一下午空调。回来后，我还是觉得有必要把这个问题解决。所以我重建了一个项目，我改的路径老是不刷新，重新部署项目都不起作用，于是我重启了电脑，等了整整十分钟，电脑的idea才卡起来，我真的是，是时候过年给自己配置一台号的电脑了。然后终于现在解决了，成功了。

FileUploadServlet

package com.zhouyajuan.servlet;

import org.apache.commons.fileupload.FileItem;
import org.apache.commons.fileupload.disk.DiskFileItemFactory;
import org.apache.commons.fileupload.servlet.ServletFileUpload;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.File;
import java.io.IOException;
import java.io.UnsupportedEncodingException;
import java.util.Iterator;
import java.util.List;

public class FileUploadServlet extends HttpServlet {
    private static final long serialVersionUID = 1L;
    private String uploadPath = "E:/SPRINGBOOT/demo/Image/web/images/"; // 上传文件的目录
    private String tempPath = "E:/SPRINGBOOT/demo/Image/web/temp/"; // 临时文件目录
    File tempPathFile;

    @Override
    public void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        //设置响应编码格式，防止乱码
        try {
            req.setCharacterEncoding("UTF-8");
        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();
        }

        //设置响应编码格式，防止乱码
        resp.setContentType("text/html;charset=UTF-8");

        try {
            // Create a factory for disk-based file items
            DiskFileItemFactory factory = new DiskFileItemFactory();

            // Set factory constraints
            //factory.setSizeThreshold(1000); // 设置缓冲区大小，这里是4kb
            factory.setRepository(tempPathFile);// 设置缓冲区目录

            // Create a new file upload handler
            ServletFileUpload upload = new ServletFileUpload(factory);

            // Set overall request size constraint
            //upload.setSizeMax(41943); // 设置最大文件尺寸，这里是4MB

            List<FileItem> items = upload.parseRequest(req);// 得到所有的文件
            Iterator<FileItem> i = items.iterator();
            while (i.hasNext()) {
                FileItem fi = (FileItem) i.next();
                String fileName = fi.getName();

                if (fileName != null) {
                    System.out.println(fileName+"filename:");
                    File fullFile = new File(fi.getName());
                    File savedFile = new File(uploadPath, fullFile.getName());
                    fi.write(savedFile);
                }
            }
            System.out.print("upload succeed");
        } catch (Exception e) {
            // 可以跳转出错页面
            e.printStackTrace();
        }
    }

    @Override
    public void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        doPost(req, resp);
    }
}

web.xml

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_4_0.xsd"
         version="4.0">
    
    <servlet>
        <servlet-name>FileUploadServlet</servlet-name>
        <servlet-class>com.zhouyajuan.servlet.FileUploadServlet</servlet-class>
    </servlet>
    <servlet-mapping>
        <servlet-name>FileUploadServlet</servlet-name>
        <url-pattern>/server/fileupload</url-pattern>
    </servlet-mapping>
</web-app>

index.jsp

<%-- Created by IntelliJ IDEA. --%>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>

<head>
  <meta http-equiv="Content-Type" content="text/html;charset=UTF-8">
  <title>WebUploader演示</title>
  <link rel="stylesheet" type="text/css" href="webuploader-0.1.4/css/webuploader.css" />
  <link rel="stylesheet" type="text/css" href="webuploader-0.1.4/examples/image-upload/style.css" />
</head>
<body>
<div id="wrapper">
  <div id="container">
    <!--头部，相册选择和格式选择-->
    <div id="uploader">
      <div class="queueList">
        <div id="dndArea" class="placeholder">
          <div id="filePicker"></div>
          <p>或将照片拖到这里，单次最多可选300张</p>
        </div>

      </div>
      <div class="statusBar" style="display:none;">
        <div class="progress">
          <span class="text">0%</span>
          <span class="percentage"></span>
        </div><div class="info"></div>
        <div class="btns">
          <div id="filePicker2"></div><div class="uploadBtn">开始上传</div>
        </div>
      </div>
    </div>
  </div>
</div>
<script type="text/javascript" src="webuploader-0.1.4/examples/image-upload/jquery.js"></script>
<script type="text/javascript" src="webuploader-0.1.4/dist/webuploader.js"></script>
<script type="text/javascript" src="webuploader-0.1.4/examples/image-upload/upload.js"></script>
</body>
</html>

upload.js

(function( $ ){
    // 当domReady的时候开始初始化
    $(function() {
        var $wrap = $('#uploader'),

            // 图片容器
            $queue = $( '<ul class="filelist"></ul>' )
                .appendTo( $wrap.find( '.queueList' ) ),

            // 状态栏，包括进度和控制按钮
            $statusBar = $wrap.find( '.statusBar' ),

            // 文件总体选择信息。
            $info = $statusBar.find( '.info' ),

            // 上传按钮
            $upload = $wrap.find( '.uploadBtn' ),

            // 没选择文件之前的内容。
            $placeHolder = $wrap.find( '.placeholder' ),

            $progress = $statusBar.find( '.progress' ).hide(),

            // 添加的文件数量
            fileCount = 0,

            // 添加的文件总大小
            fileSize = 0,

            // 优化retina, 在retina下这个值是2
            ratio = window.devicePixelRatio || 1,

            // 缩略图大小
            thumbnailWidth = 110 * ratio,
            thumbnailHeight = 110 * ratio,

            // 可能有pedding, ready, uploading, confirm, done.
            state = 'pedding',

            // 所有文件的进度信息，key为file id
            percentages = {},
            // 判断浏览器是否支持图片的base64
            isSupportBase64 = ( function() {
                var data = new Image();
                var support = true;
                data.onload = data.onerror = function() {
                    if( this.width != 1 || this.height != 1 ) {
                        support = false;
                    }
                }
                data.src = "data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///ywAAAAAAQABAAACAUwAOw==";
                return support;
            } )(),

            // 检测是否已经安装flash，检测flash的版本
            flashVersion = ( function() {
                var version;

                try {
                    version = navigator.plugins[ 'Shockwave Flash' ];
                    version = version.description;
                } catch ( ex ) {
                    try {
                        version = new ActiveXObject('ShockwaveFlash.ShockwaveFlash')
                                .GetVariable('$version');
                    } catch ( ex2 ) {
                        version = '0.0';
                    }
                }
                version = version.match( /\d+/g );
                return parseFloat( version[ 0 ] + '.' + version[ 1 ], 10 );
            } )(),

            supportTransition = (function(){
                var s = document.createElement('p').style,
                    r = 'transition' in s ||
                            'WebkitTransition' in s ||
                            'MozTransition' in s ||
                            'msTransition' in s ||
                            'OTransition' in s;
                s = null;
                return r;
            })(),

            // WebUploader实例
            uploader;

        if ( !WebUploader.Uploader.support('flash') /*&& WebUploader.browser.ie*/ ) {

            // flash 安装了但是版本过低。
            if (flashVersion) {
                (function(container) {
                    window['expressinstallcallback'] = function( state ) {
                        switch(state) {
                            case 'Download.Cancelled':
                                alert('您取消了更新！')
                                break;

                            case 'Download.Failed':
                                alert('安装失败')
                                break;

                            default:
                                alert('安装已成功，请刷新！');
                                break;
                        }
                        delete window['expressinstallcallback'];
                    };

                    var swf = './expressInstall.swf';
                    // insert flash object
                    var html = '<object type="application/' +
                            'x-shockwave-flash" data="' +  swf + '" ';

                    if (WebUploader.browser.ie) {
                        html += 'classid="clsid:d27cdb6e-ae6d-11cf-96b8-444553540000" ';
                    }

                    html += 'width="100%" height="100%" style="outline:0">'  +
                        '<param name="movie" value="' + swf + '" />' +
                        '<param name="wmode" value="transparent" />' +
                        '<param name="allowscriptaccess" value="always" />' +
                    '</object>';

                    container.html(html);

                })($wrap);

            // 压根就没有安转。
            } else {
                $wrap.html('<a href="http://www.adobe.com/go/getflashplayer" target="_blank" border="0"><img alt="get flash player" src="http://www.adobe.com/macromedia/style_guide/images/160x41_Get_Flash_Player.jpg" /></a>');
            }

            return;
        } else if (!WebUploader.Uploader.support()) {
            alert( 'Web Uploader 不支持您的浏览器！');
            return;
        }

        // 实例化
        uploader = WebUploader.create({
            pick: {
                id: '#filePicker',
                label: '点击选择图片'
            },
            formData: {
                uid: 123
            },
            dnd: '#dndArea',
            paste: '#uploader',
            swf: '../../dist/Uploader.swf',
            chunked: false,
            chunkSize: 512 * 1024,
            server: 'http://localhost:8080/Image/server/fileupload',
            // runtimeOrder: 'flash',
            // server: 'http://liaoxuezhi.fe.baidu.com/webupload/fileupload.php',
            // server: 'http://www.2betop.net/fileupload.php',
            //

            // accept: {
            //     title: 'Images',
            //     extensions: 'gif,jpg,jpeg,bmp,png',
            //     mimeTypes: 'image/*'
            // },

            // 禁掉全局的拖拽功能。这样不会出现图片拖进页面的时候，把图片打开。
            disableGlobalDnd: true,
            fileNumLimit: 300,
            fileSizeLimit: 200 * 1024 * 1024,    // 200 M
            fileSingleSizeLimit: 2 * 1024 * 1024    // 50 M
        });

        // 拖拽时不接受 js, txt 文件。
        uploader.on( 'dndAccept', function( items ) {
            var denied = false,
                len = items.length,
                i = 0,
                // 修改js类型
                unAllowed = 'text/plain;application/javascript ';

            for ( ; i < len; i++ ) {
                // 如果在列表里面
                if ( ~unAllowed.indexOf( items[ i ].type ) ) {
                    denied = true;
                    break;
                }
            }

            return !denied;
        });

        // uploader.on('filesQueued', function() {
        //     uploader.sort(function( a, b ) {
        //         if ( a.name < b.name )
        //           return -1;
        //         if ( a.name > b.name )
        //           return 1;
        //         return 0;
        //     });
        // });

        // 添加“添加文件”的按钮，
        uploader.addButton({
            id: '#filePicker2',
            label: '继续添加'
        });

        uploader.on('ready', function() {
            window.uploader = uploader;
        });

        // 当有文件添加进来时执行，负责view的创建
        function addFile( file ) {
            var $li = $( '<li id="' + file.id + '">' +
                    '<p class="title">' + file.name + '</p>' +
                    '<p class="imgWrap"></p>'+
                    '<p class="progress"><span></span></p>' +
                    '</li>' ),

                $btns = $('<div class="file-panel">' +
                    '<span class="cancel">删除</span>' +
                    '<span class="rotateRight">向右旋转</span>' +
                    '<span class="rotateLeft">向左旋转</span></div>').appendTo( $li ),
                $prgress = $li.find('p.progress span'),
                $wrap = $li.find( 'p.imgWrap' ),
                $info = $('<p class="error"></p>'),

                showError = function( code ) {
                    switch( code ) {
                        case 'exceed_size':
                            text = '文件大小超出';
                            break;

                        case 'interrupt':
                            text = '上传暂停';
                            break;

                        default:
                            text = '上传失败，请重试';
                            break;
                    }

                    $info.text( text ).appendTo( $li );
                };

            if ( file.getStatus() === 'invalid' ) {
                showError( file.statusText );
            } else {
                // @todo lazyload
                $wrap.text( '预览中' );
                uploader.makeThumb( file, function( error, src ) {
                    var img;

                    if ( error ) {
                        $wrap.text( '不能预览' );
                        return;
                    }

                    if( isSupportBase64 ) {
                        img = $('<img src="'+src+'">');
                        $wrap.empty().append( img );
                    } else {
                        $.ajax('http://localhost:8080/Image/server/fileupload', {
                            method: 'POST',
                            data: src,
                            dataType:'json'
                        }).done(function( response ) {
                            if (response.result) {
                                img = $('<img src="'+response.result+'">');
                                $wrap.empty().append( img );
                            } else {
                                $wrap.text("预览出错");
                            }
                        });
                    }
                }, thumbnailWidth, thumbnailHeight );

                percentages[ file.id ] = [ file.size, 0 ];
                file.rotation = 0;
            }

            file.on('statuschange', function( cur, prev ) {
                if ( prev === 'progress' ) {
                    $prgress.hide().width(0);
                } else if ( prev === 'queued' ) {
                    $li.off( 'mouseenter mouseleave' );
                    $btns.remove();
                }

                // 成功
                if ( cur === 'error' || cur === 'invalid' ) {
                    console.log( file.statusText );
                    showError( file.statusText );
                    percentages[ file.id ][ 1 ] = 1;
                } else if ( cur === 'interrupt' ) {
                    showError( 'interrupt' );
                } else if ( cur === 'queued' ) {
                    percentages[ file.id ][ 1 ] = 0;
                } else if ( cur === 'progress' ) {
                    $info.remove();
                    $prgress.css('display', 'block');
                } else if ( cur === 'complete' ) {
                    $li.append( '<span class="success"></span>' );
                }

                $li.removeClass( 'state-' + prev ).addClass( 'state-' + cur );
            });

            $li.on( 'mouseenter', function() {
                $btns.stop().animate({height: 30});
            });

            $li.on( 'mouseleave', function() {
                $btns.stop().animate({height: 0});
            });

            $btns.on( 'click', 'span', function() {
                var index = $(this).index(),
                    deg;

                switch ( index ) {
                    case 0:
                        uploader.removeFile( file );
                        return;

                    case 1:
                        file.rotation += 90;
                        break;

                    case 2:
                        file.rotation -= 90;
                        break;
                }

                if ( supportTransition ) {
                    deg = 'rotate(' + file.rotation + 'deg)';
                    $wrap.css({
                        '-webkit-transform': deg,
                        '-mos-transform': deg,
                        '-o-transform': deg,
                        'transform': deg
                    });
                } else {
                    $wrap.css( 'filter', 'progid:DXImageTransform.Microsoft.BasicImage(rotation='+ (~~((file.rotation/90)%4 + 4)%4) +')');
                    // use jquery animate to rotation
                    // $({
                    //     rotation: rotation
                    // }).animate({
                    //     rotation: file.rotation
                    // }, {
                    //     easing: 'linear',
                    //     step: function( now ) {
                    //         now = now * Math.PI / 180;

                    //         var cos = Math.cos( now ),
                    //             sin = Math.sin( now );

                    //         $wrap.css( 'filter', "progid:DXImageTransform.Microsoft.Matrix(M11=" + cos + ",M12=" + (-sin) + ",M21=" + sin + ",M22=" + cos + ",SizingMethod='auto expand')");
                    //     }
                    // });
                }


            });

            $li.appendTo( $queue );
        }

        // 负责view的销毁
        function removeFile( file ) {
            var $li = $('#'+file.id);

            delete percentages[ file.id ];
            updateTotalProgress();
            $li.off().find('.file-panel').off().end().remove();
        }

        function updateTotalProgress() {
            var loaded = 0,
                total = 0,
                spans = $progress.children(),
                percent;

            $.each( percentages, function( k, v ) {
                total += v[ 0 ];
                loaded += v[ 0 ] * v[ 1 ];
            } );

            percent = total ? loaded / total : 0;


            spans.eq( 0 ).text( Math.round( percent * 100 ) + '%' );
            spans.eq( 1 ).css( 'width', Math.round( percent * 100 ) + '%' );
            updateStatus();
        }

        function updateStatus() {
            var text = '', stats;

            if ( state === 'ready' ) {
                text = '选中' + fileCount + '张图片，共' +
                        WebUploader.formatSize( fileSize ) + '。';
            } else if ( state === 'confirm' ) {
                stats = uploader.getStats();
                if ( stats.uploadFailNum ) {
                    text = '已成功上传' + stats.successNum+ '张照片至XX相册，'+
                        stats.uploadFailNum + '张照片上传失败，<a class="retry" href="#">重新上传</a>失败图片或<a class="ignore" href="#">忽略</a>'
                }

            } else {
                stats = uploader.getStats();
                text = '共' + fileCount + '张（' +
                        WebUploader.formatSize( fileSize )  +
                        '），已上传' + stats.successNum + '张';

                if ( stats.uploadFailNum ) {
                    text += '，失败' + stats.uploadFailNum + '张';
                }
            }

            $info.html( text );
        }

        function setState( val ) {
            var file, stats;

            if ( val === state ) {
                return;
            }

            $upload.removeClass( 'state-' + state );
            $upload.addClass( 'state-' + val );
            state = val;

            switch ( state ) {
                case 'pedding':
                    $placeHolder.removeClass( 'element-invisible' );
                    $queue.hide();
                    $statusBar.addClass( 'element-invisible' );
                    uploader.refresh();
                    break;

                case 'ready':
                    $placeHolder.addClass( 'element-invisible' );
                    $( '#filePicker2' ).removeClass( 'element-invisible');
                    $queue.show();
                    $statusBar.removeClass('element-invisible');
                    uploader.refresh();
                    break;

                case 'uploading':
                    $( '#filePicker2' ).addClass( 'element-invisible' );
                    $progress.show();
                    $upload.text( '暂停上传' );
                    break;

                case 'paused':
                    $progress.show();
                    $upload.text( '继续上传' );
                    break;

                case 'confirm':
                    $progress.hide();
                    $upload.text( '开始上传' ).addClass( 'disabled' );

                    stats = uploader.getStats();
                    if ( stats.successNum && !stats.uploadFailNum ) {
                        setState( 'finish' );
                        return;
                    }
                    break;
                case 'finish':
                    stats = uploader.getStats();
                    if ( stats.successNum ) {
                        alert( '上传成功' );
                    } else {
                        // 没有成功的图片，重设
                        state = 'done';
                        location.reload();
                    }
                    break;
            }

            updateStatus();
        }

        uploader.onUploadProgress = function( file, percentage ) {
            var $li = $('#'+file.id),
                $percent = $li.find('.progress span');

            $percent.css( 'width', percentage * 100 + '%' );
            percentages[ file.id ][ 1 ] = percentage;
            updateTotalProgress();
        };

        uploader.onFileQueued = function( file ) {
            fileCount++;
            fileSize += file.size;

            if ( fileCount === 1 ) {
                $placeHolder.addClass( 'element-invisible' );
                $statusBar.show();
            }

            addFile( file );
            setState( 'ready' );
            updateTotalProgress();
        };

        uploader.onFileDequeued = function( file ) {
            fileCount--;
            fileSize -= file.size;

            if ( !fileCount ) {
                setState( 'pedding' );
            }

            removeFile( file );
            updateTotalProgress();

        };

        uploader.on( 'all', function( type ) {
            var stats;
            switch( type ) {
                case 'uploadFinished':
                    setState( 'confirm' );
                    break;

                case 'startUpload':
                    setState( 'uploading' );
                    break;

                case 'stopUpload':
                    setState( 'paused' );
                    break;

            }
        });

        uploader.onError = function( code ) {
            alert( 'Eroor: ' + code );
        };

        $upload.on('click', function() {
            if ( $(this).hasClass( 'disabled' ) ) {
                return false;
            }

            if ( state === 'ready' ) {
                uploader.upload();
            } else if ( state === 'paused' ) {
                uploader.upload();
            } else if ( state === 'uploading' ) {
                uploader.stop();
            }
        });

        $info.on( 'click', '.retry', function() {
            uploader.retry();
        } );

        $info.on( 'click', '.ignore', function() {
            alert( 'todo' );
        } );

        $upload.addClass( 'state-' + state );
        updateTotalProgress();
    });

})( jQuery );

 当然，需要fileupload插件，webupload框架，自己去找，去下。最后，发一张锦里的照片吧。

现在，终于可以放心的休息了。