Merge pull request #385 from liaochong/Hotfix/4.3.0.RC2

Hotfix/4.3.0.rc2

Author: liaochong

pom.xml

@@ -11,7 +11,7 @@
 
     <groupId>com.github.liaochong</groupId>
     <artifactId>myexcel</artifactId>
-    <version>4.3.0.RC2</version>
+    <version>4.3.0.RC3</version>
     <packaging>jar</packaging>
 
     <name>myexcel</name>

src/main/java/com/github/liaochong/myexcel/core/AbstractExcelFactory.java

@@ -16,6 +16,7 @@
 package com.github.liaochong.myexcel.core;
 
 import com.github.liaochong.myexcel.core.parser.ContentTypeEnum;
+import com.github.liaochong.myexcel.core.parser.DropDownLists;
 import com.github.liaochong.myexcel.core.parser.HtmlTableParser;
 import com.github.liaochong.myexcel.core.parser.Td;
 import com.github.liaochong.myexcel.core.parser.Tr;
@@ -564,29 +565,38 @@ private Cell setLink(Td td, Row currentRow, HyperlinkType hyperlinkType) {
     }
 
     private String setDropDownList(Td td, Sheet sheet, String content) {
-        if (content.length() > 250) {
-            throw new IllegalArgumentException("The total number of words in the drop-down list should not exceed 250.");
-        }
-        CellRangeAddressList addressList = new CellRangeAddressList(
+        if (content != null && !content.isEmpty()) {
+            CellRangeAddressList addressList = new CellRangeAddressList(
                 td.row, td.getRowBound(), td.col, td.getColBound());
-        DataValidationHelper dvHelper = sheet.getDataValidationHelper();
-        String[] list = content.split(",");
-        DataValidationConstraint dvConstraint = dvHelper.createExplicitListConstraint(list);
-        DataValidation validation = dvHelper.createValidation(
-                dvConstraint, addressList);
-        if (td.promptContainer != null) {
-            validation.createPromptBox(td.promptContainer.title, td.promptContainer.text);
-            validation.setShowPromptBox(true);
-        }
-        if (validation instanceof XSSFDataValidation) {
-            validation.setSuppressDropDownArrow(true);
-            validation.setShowErrorBox(true);
-        } else {
-            validation.setSuppressDropDownArrow(false);
-        }
-        sheet.addValidationData(validation);
-        if (list.length > 0) {
-            return list[0];
+            DataValidationHelper dvHelper = sheet.getDataValidationHelper();
+            String[] list;
+            DataValidation validation;
+            if (content.length() <= 250) {
+                list = content.split(",");
+                DataValidationConstraint dvConstraint = dvHelper.createExplicitListConstraint(list);
+                validation = dvHelper.createValidation(
+                    dvConstraint, addressList);
+
+            } else {
+                DropDownLists.Index index = DropDownLists.getHiddenSheetIndex(content, workbook);
+                list = new String[]{index.firstLine};
+                validation = dvHelper.createValidation(dvHelper.createFormulaListConstraint(index.path), addressList);
+            }
+
+            if (td.promptContainer != null) {
+                validation.createPromptBox(td.promptContainer.title, td.promptContainer.text);
+                validation.setShowPromptBox(true);
+            }
+            if (validation instanceof XSSFDataValidation) {
+                validation.setSuppressDropDownArrow(true);
+                validation.setShowErrorBox(true);
+            } else {
+                validation.setSuppressDropDownArrow(false);
+            }
+            sheet.addValidationData(validation);
+            if (list.length > 0) {
+                return list[0];
+            }
         }
         return null;
     }

src/main/java/com/github/liaochong/myexcel/core/parser/DropDownLists.java

@@ -0,0 +1,69 @@
+package com.github.liaochong.myexcel.core.parser;
+
+import org.apache.poi.ss.usermodel.Cell;
+import org.apache.poi.ss.usermodel.Row;
+import org.apache.poi.ss.usermodel.Sheet;
+import org.apache.poi.ss.usermodel.Workbook;
+
+import java.util.Map;
+import java.util.Objects;
+import java.util.concurrent.ConcurrentHashMap;
+
+public final class DropDownLists {
+
+    private static final Map<String, Index> INDEX = new ConcurrentHashMap<>();
+
+    private DropDownLists() {
+    }
+
+    public static Index getHiddenSheetIndex(String input, Workbook workbook) {
+        return INDEX.computeIfAbsent(input, hash -> createAndWriteHiddenSheet(input, workbook));
+    }
+
+    private static Index createAndWriteHiddenSheet(String input, Workbook workbook) {
+        String sheetName = "MyExcel_HiddenDat@List-0";
+        Sheet sheet = workbook.getSheet(sheetName);
+        if (sheet == null) {
+            sheet = workbook.createSheet(sheetName);
+            int index = workbook.getSheetIndex(sheet);
+            workbook.setSheetHidden(index, true);
+        }
+        int rowNum = sheet.getLastRowNum() + 1;
+        Row row = sheet.createRow(rowNum);
+        String[] list = input.split(",");
+        for (int i = 0; i < list.length; i++) {
+            Cell cell = row.createCell(i);
+            cell.setCellValue(list[i]);
+        }
+        int displayRowNum = rowNum + 1;
+        return new Index(list[0], rowNum, "'" + sheetName + "'!$" + displayRowNum + ":$" + displayRowNum);
+    }
+
+    public static class Index {
+
+        public String firstLine;
+
+        public int rowNum;
+
+        public String path;
+
+        public Index(String firstLine, int rowNum, String path) {
+            this.firstLine = firstLine;
+            this.rowNum = rowNum;
+            this.path = path;
+        }
+
+        @Override
+        public boolean equals(Object o) {
+            if (this == o) return true;
+            if (!(o instanceof Index)) return false;
+            Index index = (Index) o;
+            return rowNum == index.rowNum && Objects.equals(firstLine, index.firstLine) && Objects.equals(path, index.path);
+        }
+
+        @Override
+        public int hashCode() {
+            return Objects.hash(firstLine, rowNum, path);
+        }
+    }
+}