完善 Excel 导入模版下拉选择生成实现

yudao-framework/yudao-spring-boot-starter-excel/src/main/java/cn/iocoder/yudao/framework/excel/core/enums/ExcelColumn.java

@@ -0,0 +1,25 @@
+package cn.iocoder.yudao.framework.excel.core.enums;
+
+import lombok.AllArgsConstructor;
+import lombok.Getter;
+
+/**
+ * Excel 列名枚举
+ * 默认枚举 26 列列名如果有需求更多的列名请自行补充
+ *
+ * @author HUIHUI
+ */
+@Getter
+@AllArgsConstructor
+public enum ExcelColumn {
+    A(0), B(1), C(2), D(3), E(4), F(5), G(6), H(7), I(8),
+    J(9), K(10), L(11), M(12), N(13), O(14), P(15), Q(16),
+    R(17), S(18), T(19), U(20), V(21), W(22), X(23), Y(24),
+    Z(25);
+
+    /**
+     * 列索引
+     */
+    private final int colNum;
+
+}

yudao-framework/yudao-spring-boot-starter-excel/src/main/java/cn/iocoder/yudao/framework/excel/core/handler/SelectSheetWriteHandler.java

@@ -1,7 +1,9 @@
 package cn.iocoder.yudao.framework.excel.core.handler;
 
 import cn.hutool.core.collection.CollUtil;
+import cn.hutool.core.lang.Assert;
 import cn.iocoder.yudao.framework.common.core.KeyValue;
+import cn.iocoder.yudao.framework.excel.core.enums.ExcelColumn;
 import com.alibaba.excel.write.handler.SheetWriteHandler;
 import com.alibaba.excel.write.metadata.holder.WriteSheetHolder;
 import com.alibaba.excel.write.metadata.holder.WriteWorkbookHolder;
@@ -11,6 +13,8 @@ import org.apache.poi.ss.util.CellRangeAddressList;
 
 import java.util.Comparator;
 import java.util.List;
+import java.util.Map;
+import java.util.stream.Collectors;
 
 /**
  * 基于固定 sheet 实现下拉框
@@ -20,18 +24,20 @@ import java.util.List;
 public class SelectSheetWriteHandler implements SheetWriteHandler {
 
     private static final String DICT_SHEET_NAME = "字典sheet";
+    public static final int FIRST_ROW = 1; // 数据起始行从 0 开始，本项目第一行有标题所以从 1 开始如果您的 Excel 有多行标题请自行更改
+    public static final int LAST_ROW = 2000; // 下拉列需要创建下拉框的行数，默认两千行如需更多请自行调整
+    private final List<KeyValue<ExcelColumn, List<String>>> selectMap;
 
-    // TODO @puhui999：key 不使用 int 值么？感觉不是很优雅哈。
-    private final List<KeyValue<Integer, List<String>>> selectMap;
-
-    private static final char[] ALPHABET = new char[]{'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'};
-
-    public SelectSheetWriteHandler(List<KeyValue<Integer, List<String>>> selectMap) {
+    public SelectSheetWriteHandler(List<KeyValue<ExcelColumn, List<String>>> selectMap) {
         if (CollUtil.isEmpty(selectMap)) {
             this.selectMap = null;
             return;
         }
+        // 校验一下 key 是否唯一
+        Map<String, Long> nameCounts = selectMap.stream()
+                .collect(Collectors.groupingBy(item -> item.getKey().name(), Collectors.counting()));
+        Assert.isFalse(nameCounts.entrySet().stream().allMatch(entry -> entry.getValue() > 1), "下拉数据 key 重复请排查！！！");
+
         selectMap.sort(Comparator.comparing(item -> item.getValue().size())); // 升序不然创建下拉会报错
         this.selectMap = selectMap;
     }
@@ -41,16 +47,14 @@ public class SelectSheetWriteHandler implements SheetWriteHandler {
         if (CollUtil.isEmpty(selectMap)) {
             return;
         }
-        // 需要设置下拉框的 sheet 页
-        Sheet currentSheet = writeSheetHolder.getSheet();
-        DataValidationHelper helper = currentSheet.getDataValidationHelper();
-        Workbook workbook = writeWorkbookHolder.getWorkbook();
 
-        // 数据字典的 sheet 页
+        // 1.1 获取相应操作对象
+        DataValidationHelper helper = writeSheetHolder.getSheet().getDataValidationHelper(); // 需要设置下拉框的 sheet 页的数据验证助手
+        Workbook workbook = writeWorkbookHolder.getWorkbook(); // 获得工作簿
+
+        // 1.2 创建数据字典的 sheet 页
         Sheet dictSheet = workbook.createSheet(DICT_SHEET_NAME);
-        for (KeyValue<Integer, List<String>> keyValue : selectMap) {
-            // 设置下拉单元格的首行、末行、首列、末列
-            CellRangeAddressList rangeAddressList = new CellRangeAddressList(1, 65533, keyValue.getKey(), keyValue.getKey());
+        for (KeyValue<ExcelColumn, List<String>> keyValue : selectMap) {
             int rowLen = keyValue.getValue().size();
             // 设置字典 sheet 页的值 每一列一个字典项
             for (int i = 0; i < rowLen; i++) {
@@ -58,58 +62,42 @@ public class SelectSheetWriteHandler implements SheetWriteHandler {
                 if (row == null) {
                     row = dictSheet.createRow(i);
                 }
-                row.createCell(keyValue.getKey()).setCellValue(keyValue.getValue().get(i));
+                row.createCell(keyValue.getKey().getColNum()).setCellValue(keyValue.getValue().get(i));
             }
-
-            // TODO @puhui999：下面 1. 2.1 2.2 2.3 我是按照已经理解的，调整了下格式；这样可读性更好；在 52 到 62 行，你可以看看，是不是也弄下序号；
-            // 1. 创建可被其他单元格引用的名称
-            Name name = workbook.createName();
-            // TODO @puhui999：下面的 excelColumn 和 refers 两行，是不是可以封装成一个方法，替代 getExcelColumn；
-            String excelColumn = getExcelColumn(keyValue.getKey());
-            String refers = DICT_SHEET_NAME + "!$" + excelColumn + "$1:$" + excelColumn + "$" + rowLen; // 下拉框数据来源 eg:字典sheet!$B1:$B2
-            name.setNameName("dict" + keyValue.getKey()); // 设置名称的名字
-            name.setRefersToFormula(refers); // 设置公式
-
-            // 2.1 设置约束
-            DataValidationConstraint constraint = helper.createFormulaListConstraint("dict" + keyValue.getKey()); // 设置引用约束
-            DataValidation validation = helper.createValidation(constraint, rangeAddressList);
-            if (validation instanceof HSSFDataValidation) {
-                validation.setSuppressDropDownArrow(false);
-            } else {
-                validation.setSuppressDropDownArrow(true);
-                validation.setShowErrorBox(true);
-            }
-            // 2.2 阻止输入非下拉框的值
-            validation.setErrorStyle(DataValidation.ErrorStyle.STOP);
-            validation.createErrorBox("提示", "此值不存在于下拉选择中！");
-            // 2.3 添加下拉框约束
-            writeSheetHolder.getSheet().addValidationData(validation);
+            // 1.3 设置单元格下拉选择
+            setColSelect(writeSheetHolder, workbook, helper, keyValue);
         }
     }
 
     /**
-     * 将数字列转化成为字母列
-     *
-     * @param num 数字
-     * @return 字母
+     * 设置单元格下拉选择
      */
-    // TODO @puhui999：这个是必须字母列哇？还是数字其实也可以哈？主要想看看，怎么能把这个逻辑，进一步简化
-    private String getExcelColumn(int num) {
-        String column;
-        int len = ALPHABET.length - 1;
-        int first = num / len;
-        int second = num % len;
-        if (num <= len) {
-            column = ALPHABET[num] + "";
+    private static void setColSelect(WriteSheetHolder writeSheetHolder, Workbook workbook, DataValidationHelper helper,
+                                     KeyValue<ExcelColumn, List<String>> keyValue) {
+        // 1.1 创建可被其他单元格引用的名称
+        Name name = workbook.createName();
+        String excelColumn = keyValue.getKey().name();
+        // 1.2 下拉框数据来源 eg:字典sheet!$B1:$B2
+        String refers = DICT_SHEET_NAME + "!$" + excelColumn + "$1:$" + excelColumn + "$" + keyValue.getValue().size();
+        name.setNameName("dict" + keyValue.getKey()); // 设置名称的名字
+        name.setRefersToFormula(refers); // 设置公式
+        // 2.1 设置约束
+        DataValidationConstraint constraint = helper.createFormulaListConstraint("dict" + keyValue.getKey()); // 设置引用约束
+        // 设置下拉单元格的首行、末行、首列、末列
+        CellRangeAddressList rangeAddressList = new CellRangeAddressList(FIRST_ROW, LAST_ROW,
+                keyValue.getKey().getColNum(), keyValue.getKey().getColNum());
+        DataValidation validation = helper.createValidation(constraint, rangeAddressList);
+        if (validation instanceof HSSFDataValidation) {
+            validation.setSuppressDropDownArrow(false);
         } else {
-            column = ALPHABET[first - 1] + "";
-            if (second == 0) {
-                column = column + ALPHABET[len];
-            } else {
-                column = column + ALPHABET[second - 1];
-            }
+            validation.setSuppressDropDownArrow(true);
+            validation.setShowErrorBox(true);
         }
-        return column;
+        // 2.2 阻止输入非下拉框的值
+        validation.setErrorStyle(DataValidation.ErrorStyle.STOP);
+        validation.createErrorBox("提示", "此值不存在于下拉选择中！");
+        // 2.3 添加下拉框约束
+        writeSheetHolder.getSheet().addValidationData(validation);
     }
 
 }

yudao-framework/yudao-spring-boot-starter-excel/src/main/java/cn/iocoder/yudao/framework/excel/core/util/ExcelUtils.java

@@ -1,6 +1,7 @@
 package cn.iocoder.yudao.framework.excel.core.util;
 
 import cn.iocoder.yudao.framework.common.core.KeyValue;
+import cn.iocoder.yudao.framework.excel.core.enums.ExcelColumn;
 import cn.iocoder.yudao.framework.excel.core.handler.SelectSheetWriteHandler;
 import com.alibaba.excel.EasyExcel;
 import com.alibaba.excel.converters.longconverter.LongStringConverter;
@@ -44,11 +45,11 @@ public class ExcelUtils {
      * @param sheetName Excel sheet 名
      * @param head      Excel head 头
      * @param data      数据列表哦
-     * @param selectMap 下拉选择数据 Map
+     * @param selectMap 下拉选择数据 Map<下拉所对应的列表名，下拉数据>
      * @throws IOException 写入失败的情况
      */
     public static <T> void write(HttpServletResponse response, String filename, String sheetName,
-                                 Class<T> head, List<T> data, List<KeyValue<Integer, List<String>>> selectMap) throws IOException {
+                                 Class<T> head, List<T> data, List<KeyValue<ExcelColumn, List<String>>> selectMap) throws IOException {
         // 输出 Excel
         EasyExcel.write(response.getOutputStream(), head)
                 .autoCloseStream(false) // 不要自动关闭，交给 Servlet 自己处理