EasyExcel导入导出下载模板（带下拉）

EasyExcel导入导出网上资料很多，这里就不多做描述了，总之就是一款比较轻而小，易用的excel操作工具包；这里在项目中使用到，做下笔记。以及表格中下拉框的实现；
声明：本文思路是借鉴于某大神的，然后自己进行二次改版而成的，用注解的方式来进行动态下拉列表的绑定。所以代码略微有点多。还有另一种方式，则是将数据源传入进来直接进行绑定，这样可以做到真正的与业务分离，可以更加灵活。

EasyExcel导入

EasyExcel.read(file.getInputStream(), ImportSecurityPerson.class,new PeronDataListener(securityPersonService, dto)).sheet(0).doRead();

这里一句话就可以导入成功，参数为文件流，需要导出的表格的表头实体类，第三个是读取时的监听类即可。实体类如下：

@Data
@ToString(callSuper = true)
@ApiModel(value = " 安保人员导入 ", description = " 安保人员导入 ")
public class ImportSecurityPerson {/** 安保公司name **/@ApiModelProperty(value = "安保公司name")@ExcelProperty(value = "公司名称(必填)",index = 0)private String securityCompanyName;/** 安保人员姓名 **/@ApiModelProperty(value = "安保人员姓名")@ExcelProperty(value = "人员姓名(必填)",index = 1)private String securityPersonName;/** 安保人员性别 **/@ApiModelProperty(value = "安保人员性别")@ExcelProperty(value = "性别(必填)",index = 2)private String sexCode;/** 在职状态 **/@ApiModelProperty(value = "在职状态")@ExcelProperty(value = "状态(必填)",index = 3)private String inPostStatusCode;/** 作业区 **/@ApiModelProperty(value = "作业区")@ExcelProperty(value = "作业区(必填)",index = 4)private String workZoneCode;/** 学历 **/@ApiModelProperty(value = "学历")@ExcelProperty(value = "学历",index = 5)private String eduLevelCode;@ApiModelProperty(value = "错误信息")@ExcelIgnoreprivate String msg;@ExcelIgnoreprivate String uuid;}

ExcelProperty 需要导出的表格属性，ExcelIgnore 忽略此属性。index则是顺序，value是标题；监听类中有三个重要的方法：invokeHeadMap(Map<Integer, String> headMap, AnalysisContext context)：此方法可以进行头部标题判断，判断是否是需要导入的表格；invoke(ImportSecurityPerson data, AnalysisContext context)：每解析一行便会回调此方法，可以在这个方法中做一些处理；doAfterAllAnalysed(AnalysisContext context)：解析完成所有数据后执行此方法，可以进行批量入库，导入成功，错误的信息反馈（如导入成功条数，错误条数）等。

EasyExcel导出

response.setContentType("application/vnd.ms-excel");
response.setCharacterEncoding("utf-8");
String fileName = URLEncoder.encode("安保人员", "UTF-8").replaceAll("\\+", "%20");
response.setHeader("Content-disposition", "attachment;filename*=utf-8''" + fileName + ".xlsx");
List<SecurityPersonVo> securityPersonVos = securityPersonService.listSecurityPersons(getUserCharacter(), dto);
EasyExcel.write(response.getOutputStream(), SecurityPersonVo.class).sheet(0).sheetName("人员").doWrite(securityPersonVos);

首先设置response的信息，securityPersonVos 为数据源。导出的参数为第一个：输出流；第二个：导出的实体类，和导入是一样的；导出非常简单，对于样式的话，也可以在write后进行调用registerWriteHandler方法，写自定义样式就可以满足。

EasyExcel下载模板

其实下载模板和导出是一样的，只是在这里加了一些初始化的数据，如下拉内容项。下载模板的实体类有一点点特殊，就是采用了注解方式进行绑定下拉的内容。进入正题：

response.setContentType("application/vnd.openxmlformats-officedocument.spreadsheetml.sheet");
response.setCharacterEncoding("utf-8");
String fileName = URLEncoder.encode("安保人员导入模板", "UTF-8").replaceAll("\\+", "%20");
response.setHeader("Content-disposition", "attachment;filename*=utf-8''" + fileName + ".xlsx");
//用作需要传入的入参，如无须参数，则为空
Map<String, String> map = new HashMap<>();
map.put("clientId", user.getCustomerId());
ExcelWriter excelWriter = EasyExcel.write(response.getOutputStream()).build();
WriteSheet writeSheet = EasyExcelUtil.writeSelectedSheet(DownLoadSecurityPerson.class,0, "安保人员", map);//写
excelWriter.write(new ArrayList<String>(), writeSheet);
//手动关闭
excelWriter.finish();

以上是下载模板的代码，具体看下这个工具类：EasyExcelUtil

我们先看下表格实体类：

@Data
@ToString(callSuper = true)
@ApiModel(value = " 治安人员导入 ", description = " 治安人员导入 ")
public class DownLoadSecurityPerson {/** 安保公司name **/@ApiModelProperty(value = "安保公司name")@ExcelProperty(value = "公司名称(必填)",index = 0)private String securityCompanyName;/** 安保人员姓名 **/@ApiModelProperty(value = "安保人员姓名")@ExcelProperty(value = "人员姓名(必填)",index = 1)private String securityPersonName;/** 安保人员性别 **/@ApiModelProperty(value = "安保人员性别")@ExcelSelected(source = {"男","女"})@ExcelProperty(value = "性别(必填)",index = 2)private String sexCode;/** 在职状态 **/@ApiModelProperty(value = "在职状态")@ExcelSelected(source = {"在职","离职"})@ExcelProperty(value = "状态(必填)",index = 3)private String inPostStatusCode;/** 作业区 **/@ApiModelProperty(value = "作业区")@ExcelSelected(sourceClass = ZoneExcelSelectImpl.class)@ExcelProperty(value = "作业区(必填)",index = 4)private String workZoneCode;/** 学历 **/@ApiModelProperty(value = "学历")@ExcelSelected(sourceClass = EduExcelSelectImpl.class)@ExcelProperty(value = "学历",index = 5)private String eduLevelCode;
}

模板标题类属性使用了ExcelSelected注解，用来绑定下拉内容，如何是固定的值，则采用source 来赋予，如果是动态的，则动态获取绑定。

注解类

@Documented
@Retention(RetentionPolicy.RUNTIME)
@Target(ElementType.FIELD)
public @interface ExcelSelected {/*** 固定下拉内容*/String[] source() default {};/*** 动态下拉内容*/Class<? extends ExcelDynamicSelect>[] sourceClass() default {};/*** 设置下拉框的起始行，默认为第二行*/int firstRow() default 1;/*** 设置下拉框的结束行，默认为最后一行*/int lastRow() default 0x10000;
}

注解解析类

@Data
@Slf4j
public class ExcelSelectedResolve {/*** 下拉内容*/private String[] source;/*** 设置下拉框的起始行，默认为第二行*/private int firstRow;/*** 设置下拉框的结束行，默认为最后一行*/private int lastRow;public String[] resolveSelectedSource(ExcelSelected excelSelected, Map<String,String> map) {if (excelSelected == null) {return null;}// 获取固定下拉框的内容String[] source = excelSelected.source();if (source.length > 0) {return source;}// 获取动态下拉框的内容Class<? extends ExcelDynamicSelect>[] classes = excelSelected.sourceClass();if (classes.length > 0) {try {ExcelDynamicSelect excelDynamicSelect = classes[0].newInstance();String[] dynamicSelectSource = excelDynamicSelect.getSource(map);if (dynamicSelectSource != null && dynamicSelectSource.length > 0) {return dynamicSelectSource;}} catch (InstantiationException | IllegalAccessException e) {log.error("解析动态下拉框数据异常", e);}}return null;}
}

动态数据源接口

public interface ExcelDynamicSelect {/*** 获取动态生成的下拉框可选数据* @return 动态生成的下拉框可选数据*/String[] getSource(Map<String,String> map);
}

动态数据源实现类

public class EduExcelSelectImpl implements ExcelDynamicSelect{@Overridepublic String[] getSource(Map<String,String> map) {SecurityPersonService bean = SpringContextUtil.getBean(SecurityPersonService.class);Map<String, String> stringStringMap = bean.mapDict();Collection<String> values = stringStringMap.values();return values.toArray(new String[values.size()]);}
}public class ZoneExcelSelectImpl implements ExcelDynamicSelect{@Overridepublic String[] getSource(Map<String,String> map) {SecurityPersonService bean = SpringContextUtil.getBean(SecurityPersonService.class);Map<String, String> stringStringMap = bean.mapCustomerDict(map.get("clientId"));Collection<String> values = stringStringMap.values();return values.toArray(new String[values.size()]);}
}

接下来是工具类

public class EasyExcelUtil {/*** 创建即将导出的sheet页（sheet页中含有带下拉框的列）* @param head 导出的表头信息和配置* @param sheetNo sheet索引* @param sheetName sheet名称* @param map 入参* @return sheet页*/public static <T> WriteSheet writeSelectedSheet(Class<T> head, Integer sheetNo, String sheetName,Map<String,String> map) {Map<Integer, ExcelSelectedResolve> selectedMap = this.resolveSelectedAnnotation(head,map);return EasyExcel.writerSheet(sheetNo, sheetName).head(head).registerWriteHandler(new CommentWriteHandler()) //创建批注.registerWriteHandler(new CustomColumnWidthStyle()) //自适应宽度.registerWriteHandler(new CustomSheetWriteHandler(selectedMap)) //绑定下拉数据源.build();}/*** 解析表头类中的下拉注解* @param head 表头类* @param <T> 泛型* @return Map<下拉框列索引, 下拉框内容> map*/private static <T> Map<Integer, ExcelSelectedResolve> resolveSelectedAnnotation(Class<T> head,Map<String,String> map) {//用来存储对应的列与值对象Map<Integer, ExcelSelectedResolve> selectedMap = new HashMap<>();// getDeclaredFields(): 返回全部声明的属性；getFields(): 返回public类型的属性Field[] fields = head.getDeclaredFields();for (int i = 0; i < fields.length; i++){Field field = fields[i];// 解析注解信息ExcelSelected selected = field.getAnnotation(ExcelSelected.class);ExcelProperty property = field.getAnnotation(ExcelProperty.class);if (selected != null) {ExcelSelectedResolve excelSelectedResolve = new ExcelSelectedResolve();String[] source = excelSelectedResolve.resolveSelectedSource(selected,map);if (source != null && source.length > 0){excelSelectedResolve.setSource(source);excelSelectedResolve.setFirstRow(selected.firstRow());excelSelectedResolve.setLastRow(selected.lastRow());if (property != null && property.index() >= 0){selectedMap.put(property.index(), excelSelectedResolve);} else {selectedMap.put(i, excelSelectedResolve);}}}}return selectedMap;}
}

最重要的在绑定类CustomSheetWriteHandler

@Data
@AllArgsConstructor
public class CustomSheetWriteHandler implements SheetWriteHandler {private final Map<Integer, ExcelSelectedResolve> selectedMap;@Overridepublic void beforeSheetCreate(WriteWorkbookHolder writeWorkbookHolder, WriteSheetHolder writeSheetHolder) {}@Overridepublic void afterSheetCreate(WriteWorkbookHolder writeWorkbookHolder, WriteSheetHolder writeSheetHolder) {// 区间设置 第一列第一行和第二行的数据。由于第一行是头，所以第一、二行的数据实际上是第二三行// 这里可以对cell进行任何操作Sheet sheet = writeSheetHolder.getSheet();DataValidationHelper helper = sheet.getDataValidationHelper();selectedMap.forEach((k, v) -> {// 设置下拉列表的行： 首行，末行，首列，末列CellRangeAddressList rangeList = new CellRangeAddressList(v.getFirstRow(), v.getLastRow(), k, k);// 设置下拉列表的值DataValidationConstraint constraint = helper.createExplicitListConstraint(v.getSource());// 设置约束DataValidation validation = helper.createValidation(constraint, rangeList);// 阻止输入非下拉选项的值validation.setErrorStyle(DataValidation.ErrorStyle.STOP);validation.setShowErrorBox(true);validation.setSuppressDropDownArrow(true);validation.createErrorBox("提示", "请选择下拉选项中的内容");sheet.addValidationData(validation);});}
}

至此，就完成了下载模板带有下拉选项的表格。
完整代码GitHub： https://github.com/qinyunsurd/EasyExcel