java+layui的Excel导入导出

html：

<button class="layui-btn" onclick="exportData();">导出</button>
<button class="layui-btn" onclick="downloadTemplate();">模板下载</button>
<button id="importData" class="layui-btn" onclick="importData()">导入</button>

js：

//导入 用layui upload插件
layui.use([ "element", "laypage", "layer", "upload"], function() {
    var element = layui.element;
    var laypage = layui.laypage;
    var layer = layui.layer;
    var upload = layui.upload;//主要是这个
    layui.upload.render({
        elem: "#importData",//导入id
        url: "/xx/importData",
        size: '3072',
        accept: "file",
        exts: 'xls|xlsx|xlsm|xlt|xltx|xltm',
        done: function (result) {
            if (result.status == 0) {
                refreshTable()
            }
            if (result.message != null) {
                refreshTable();
                layer.msg(result.message)
            }
        }
    });
    refreshTable()
});

//导出
function exportData() {
    $.ajax({
        type: "post", url: "/xx/exportData", data: {}, success: function (result) {
            if (result.status == 0) {
                window.open(result.data)
            }
            if (result.message != null) {
                layer.msg(result.message)
            }
        }, error: function (XMLHttpRequest, textStatus, errorThrown) {
            layer.msg('{"status":"' + XMLHttpRequest.status + '","readyState":"' + XMLHttpRequest.readyState + '","textStatus":"' + textStatus + '","errorThrown":"' + errorThrown + '"}')
        }
    })
};

//模板下载
function downloadTemplate() {
    $.ajax({
        type: "post", url: "/xx/downloadTemplate", data: {}, success: function (result) {
            if (result.status == 0) {
                window.open(result.data)
            }
            if (result.message != null) {
                layer.msg(result.message)
            }
        }, error: function (XMLHttpRequest, textStatus, errorThrown) {
            layer.msg('{"status":"' + XMLHttpRequest.status + '","readyState":"' + XMLHttpRequest.readyState + '","textStatus":"' + textStatus + '","errorThrown":"' + errorThrown + '"}')
        }
    })
}

java后端：

 // 导入
    @PostMapping(value = "importData")
    ResultJson importData(@RequestParam MultipartFile file) {
        ResultJson resultJson = new ResultJson();
        List<ProjectJson> importData = null;
        try {
            importData = ExcelUtil.importExcel(file.getInputStream(), ProjectJson.class);
        } catch (IOException e) {
            e.printStackTrace();
        }
        if (null == importData) {
            resultJson.setStatus(1);
            resultJson.setMessage("导入失败！");
            return resultJson;
        }
        int num = 0;

        for (ProjectJson projectJson : importData) {
            ProjectManageEntity projectManageEntity = new ProjectManageEntity();
            num++;
            if (CommonUtil.isEmpty(projectJson.getNumber())) {
                resultJson.setMessage("导入失败！第" + num + "行的编号不能为空");
                resultJson.setStatus(1);
                return resultJson;
            }
            if (projectService.findByprojectNumber(projectJson.getNumber()) != null) {
                resultJson.setStatus(1);
                resultJson.setMessage("导入失败！第" + num + "行的编号重复");
                resultJson.setData(null);
                return resultJson;
            }

            projectManageEntity.setCreateDate(new Date());
            projectManageEntity.setUpdateDate(new Date());
            projectManageEntity.setName(projectJson.getName());
            projectManageEntity.setNumber(projectJson.getNumber());
            projectManageEntity.setType(projectJson.getType());
            projectManageEntity.setDeleteMark(false);
            projectManageEntity.setCode("PROJECT_MANAGE" + UUID.randomUUID());
            projectService.save(projectManageEntity);
        }

        resultJson.setStatus(0);
        resultJson.setMessage("导入成功！");
        resultJson.setData(null);
        return resultJson;
    }

    //导出
    @PostMapping(value = "exportData")
    ResultJson exportData() {
        String excelTitle = "项目管理";
        String path = "/export/company/excel/" + DateUtil.getEightDateFormat().format(new Date());
        String realPath = CommonUtil.createFolderPath(propertyUtil.getUploadPath() + path);

        return ExcelUtil.exportExcel(excelTitle, realPath, path, ProjectJson.class, projectService.getAll());
    }

    //下载模板
    @PostMapping(value = "downloadTemplate")
    public ResultJson downloadTemplate() {
        String excelTitle = "项目管理模板";
        String path = "/export/company/excel/" + DateUtil.getEightDateFormat().format(new Date());
        String realPath = CommonUtil.createFolderPath(propertyUtil.getUploadPath() + path);
        return ExcelUtil.exportExcel(excelTitle, realPath, path, ProjectJson.class, projectService.getDownloadTemplate());
    }

/**
     * 创建指定目录
     *
     * @param folderPath 目录地址
     * @return 目录地址
     */
    public static final String createFolderPath(String folderPath) {
        File file = new File(folderPath);
        if (System.getProperty("os.name").toLowerCase().startsWith("win")) {
            String[] diskNames = {"A:", "B:", "C:", "D:", "E:", "F:", "G:", "H:", "I:", "J:", "K:", "L:", "M:", "N:",
                    "O:", "P:", "Q:", "R:", "S:", "T:", "U:", "V:", "W:", "X:", "Y:", "Z:"};
            for (int i = 0; i < diskNames.length; i++) {
                if (i > 0) {
                    folderPath = folderPath.replace(diskNames[i - 1], diskNames[i]);
                } else {
                    folderPath = diskNames[0] + folderPath;
                }
                file = new File(folderPath);
                if (!file.exists()) {
                    file.mkdirs();
                }
                if (file.exists()) {
                    return folderPath;
                }
            }
            return null;
        } else {
            if (!file.exists()) {
                file.mkdirs();
            }
            if (file.exists()) {
                return folderPath;
            }
            return null;
        }
    }

public class ExcelUtil {

    /**
     * 导入Excel
     * 
     * @param inputstream
     *            Excel数据流
     * @param clazz
     *            注解的实体类
     * @return 导入的数据
     */
    public static <T> List<T> importExcel(InputStream inputstream, Class<T> clazz) {
        ImportParams params = new ImportParams();
        params.setTitleRows(1);
        params.setNeedSave(true);
        try {
            return ExcelImportUtil.importExcel(inputstream, clazz, params);
        } catch (Exception e) {
            e.printStackTrace();
            return null;
        }
    }

    /**
     * 导出Excel
     * 
     * @param excelTitle
     *            Excel标题
     * @param realPath
     *            真实路径
     * @param path
     *            响应路径
     * @param clazz
     *            注解的实体类
     * @param excels
     *            注解的实体类集合
     * @return 响应结果
     */
    public static <T> ResultJson exportExcel(String excelTitle, String realPath, String path, Class<T> clazz,
            List<T> excels) {
        ResultJson resultJson = new ResultJson();
        try {
            Workbook workbook = ExcelExportUtil.exportExcel(new ExportParams(excelTitle, excelTitle), clazz, excels);
            String filename = excelTitle + "-" + DateUtil.getEightDateFormat().format(new Date()) + ".xls";
            File dirPath = new File(realPath);
            if (!dirPath.exists()) {
                dirPath.mkdirs();
            }
            try {
                FileOutputStream outputStream = new FileOutputStream(realPath + "/" + filename);
                workbook.write(outputStream);
                resultJson.setStatus(0);
                resultJson.setData(path + "/" + filename);
            } catch (Exception e) {
                e.printStackTrace();
                resultJson.setStatus(1);
                return resultJson;
            }
        } catch (Exception e) {
            e.printStackTrace();
            resultJson.setStatus(1);
            return resultJson;
        }
        return resultJson;
    }

}