fix convert bug

hutool-poi/src/main/java/cn/hutool/poi/excel/reader/BeanSheetReader.java

@@ -42,7 +42,7 @@ public class BeanSheetReader<T> implements SheetReader<List<T>> {
 
 		final List<T> beanList = new ArrayList<>(mapList.size());
 		for (Map<String, Object> map : mapList) {
-			beanList.add(BeanUtil.toBean(map, this.beanClass));
+			beanList.add(BeanUtil.toBeanIgnoreError(map, this.beanClass));
 		}
 		return beanList;
 	}

hutool-poi/src/test/java/cn/hutool/poi/excel/Issue1729Test.java

@@ -0,0 +1,30 @@
+package cn.hutool.poi.excel;
+
+import lombok.Data;
+import org.junit.Assert;
+import org.junit.Test;
+
+import java.util.List;
+
+/**
+ * issue#1729@Github<br>
+ * 日期为空时返回""而非null，因此会导致日期等字段的转换错误，此处转bean时忽略错误。
+ */
+public class Issue1729Test {
+
+	@Test
+	public void readTest() {
+		final ExcelReader reader = ExcelUtil.getReader("UserProjectDO.xlsx");
+		final List<UserProjectDO> read = reader.read(0, 1, UserProjectDO.class);
+		Assert.assertEquals("aa", read.get(0).getProjectName());
+		Assert.assertNull(read.get(0).getEndTrainTime());
+		Assert.assertEquals("2020-02-02", read.get(0).getEndTestTime().toString());
+	}
+
+	@Data
+	public static class UserProjectDO {
+		private String projectName;
+		private java.sql.Date endTrainTime;
+		private java.sql.Date endTestTime;
+	}
+}