try fix #142

hsweb-boost/hsweb-boost-excel/src/main/java/org/hswebframework/web/excel/DefaultExcelImporter.java

@@ -94,7 +94,7 @@ public class DefaultExcelImporter implements ExcelImporter {
     }
 
     @SneakyThrows
-    protected <T> ExcelCellConverter<T> createConvert(Class<ExcelCellConverter> converterClass, Class<T> type) {
+    protected <T> ExcelCellConverter<T> createConvert(Class<? extends ExcelCellConverter> converterClass, Class<T> type) {
         if (converterClass != ExcelCellConverter.class) {
             try {
                 return ApplicationContextHolder.get().getBean(converterClass);

hsweb-boost/hsweb-boost-excel/src/main/java/org/hswebframework/web/excel/Excel.java

@@ -55,6 +55,6 @@ public @interface Excel {
      * @return 实例必须注入到spring容器中
      * @see org.springframework.context.ApplicationContext#getBean(Class)
      */
-    Class<ExcelCellConverter> converter() default ExcelCellConverter.class;
+    Class<? extends ExcelCellConverter> converter() default ExcelCellConverter.class;
 
 }