fix code

hutool-db/src/main/java/cn/hutool/db/meta/ResultColumn.java

@@ -151,17 +151,16 @@ public class ResultColumn {
 		return className;
 	}
 
-	public static enum ColumnNullable {
+	public enum ColumnNullable {
 		NO_NULLS(ResultSetMetaData.columnNoNulls),
 		NULLABLE(ResultSetMetaData.columnNullable),
 		UNKNOWN(ResultSetMetaData.columnNullableUnknown);
 
-		final int value;
-
-		private ColumnNullable(final int value) {
-			this.value = value;
-		}
-
+		/**
+		 * ResultSetMetaData中的int值转枚举
+		 * @param nullable nullable值
+		 * @return ColumnNullable
+		 */
 		public static ColumnNullable of(final int nullable) {
 			switch (nullable) {
 				case ResultSetMetaData.columnNoNulls:
@@ -172,5 +171,10 @@ public class ResultColumn {
 					return UNKNOWN;
 			}
 		}
+
+		final int value;
+		ColumnNullable(final int value) {
+			this.value = value;
+		}
 	}
 }

hutool-db/src/main/java/cn/hutool/db/sql/ConditionGroup.java

@@ -13,6 +13,7 @@ import java.util.List;
  * @since 5.7.21
  */
 public class ConditionGroup extends Condition {
+	private static final long serialVersionUID = 1L;
 	/**
 	 * 条件列表
 	 */