source: WIP, インポート忘れ

source/src/main/java/one/nem/lacerta/source/database/entity/Document.java

@@ -4,6 +4,8 @@ import androidx.room.ColumnInfo;
 import androidx.room.Entity;
 import androidx.room.PrimaryKey;
 
+import java.util.Date;
+
 @Entity(tableName = "document")
 public class Document {
     @PrimaryKey