优化Excel自定义格式样式重复创建问题

ruoyi-common/src/main/java/com/ruoyi/common/utils/poi/ExcelUtil.java

@@ -106,6 +106,11 @@ public class ExcelUtil<T>
      */
     public Map<String, String> sysDictMap = new HashMap<String, String>();
 
+    /**
+     * 单元格样式缓存
+     */
+    private Map<String, CellStyle> cellStyleCache = new HashMap<String, CellStyle>();
+
     /**
      * Excel sheet最大行数，默认65536
      */
@@ -418,7 +423,7 @@ public class ExcelUtil<T>
                     Object val = this.getCellValue(row, entry.getKey());
 
                     // 如果不存在实例则新建.
-                    entity = (entity == null ? clazz.getDeclaredConstructor().newInstance() : entity);
+                    entity = (entity == null ? clazz.newInstance() : entity);
                     // 从map中得到对应列的field.
                     Field field = (Field) entry.getValue()[0];
                     Excel attr = (Excel) entry.getValue()[1];
@@ -1125,7 +1130,7 @@ public class ExcelUtil<T>
      * 添加单元格
      */
     @SuppressWarnings("deprecation")
-	public Cell addCell(Excel attr, Row row, T vo, Field field, int column)
+    public Cell addCell(Excel attr, Row row, T vo, Field field, int column)
     {
         Cell cell = null;
         try
@@ -1202,9 +1207,16 @@ public class ExcelUtil<T>
      */
     private CellStyle createCellStyle(CellStyle cellStyle, String format)
     {
+        String key = cellStyle.getIndex() + "|" + format;
+        CellStyle cached = cellStyleCache.get(key);
+        if (cached != null)
+        {
+            return cached;
+        }
         CellStyle style = wb.createCellStyle();
         style.cloneStyleFrom(cellStyle);
         style.setDataFormat(wb.getCreationHelper().createDataFormat().getFormat(format));
+        cellStyleCache.put(key, style);
         return style;
     }
 
@@ -1426,7 +1438,7 @@ public class ExcelUtil<T>
     {
         try
         {
-            Object instance = excel.handler().getDeclaredConstructor().newInstance();
+            Object instance = excel.handler().newInstance();
             Method formatMethod = excel.handler().getMethod("format", new Class[] { Object.class, String[].class, Cell.class, Workbook.class });
             value = formatMethod.invoke(instance, value, excel.args(), cell, this.wb);
         }