ORMLite抽象类的外部集合
我有4个班级：
@DatabaseTable(tableName = "bucket")
public class Bucket {
...
@ForeignCollectionField(eager = true)
private Collection<Good> goods;
...
}
public abstract class Good {
...
@DatabaseField(foreign = true, foreignAutoCreate = true, foreignAutoRefresh = true)
private Bucket bucket;
...
}
@DatabaseTable(tableName = "bread")
public class Bread extends Good {
...
}
@DatabaseTable(tableName = "milk")
public class Milk extends Good {
...
}
所以，在Bucket里面我有ForeignCollectionField的抽象类Good ，当然，它没有自己的数据库表。
数据库条目正常创建，但是当我尝试调用queryForAll()它给我错误：
bucketDao.queryForAll();
// no such table: good (code 1): , while compiling: SELECT * FROM `basecard` WHERE `bucket_id` = ?
有没有办法解决这个问题？
或者我甚至不能创建抽象类的ForeignCollectionField？
我发现解决这个问题非常简单。
我只是从Bucket模型中删除了@ForeignCollectionField 。 所以，Inside Bucket表ORMLite对Good实体一无所知。
坚持数据：
// 1 using bucketDao add bucket
bucketDao.add(bucket)
// 2 iterate over collection
for (Bread bread: breadList) {
bread.setBucket(bucket); // set current bucket to good item
breadDao.add(bread); // using breadDao add bread
}
// 3 do the same with milk collection
for (Milk milk: milkList) {
milk.setBucket(bucket);
milkDao.add(milk);
}
加载数据：
int bucketId = 1; // for example working with bucket with id=1
Bucket bucket = bucketDao.queryForEq("id", bucketId)); // query for this bucket
List<Milk> milkList = milkDao.queryForEq("bucket_id", bucketId); // query for all milks, that has a foreign key to current bucket
List<Break> breadList = breadDao.queryForEq("bucket_id", bucketId); // the same for bread
// finally set milks and breads to Good collection inside Bucket
List<Good> goodList = new ArrayList<>();
goodList.addAll(milkList);
goodList.addAll(breadList);
bucket.setGoods(goodList);