android-ORMLite多对多关系

概述为了用ORMLite在这两个类之间建立多对多关系：@DatabaseTable(tableName="test1")publicclassTest1{@ForeignCollectionFieldprivateForeignCollection<Test2>test2Collection;}@DatabaseTable(tableName="test2")publicclassTest2{

为了用Ormlite在这两个类之间建立多对多关系：

@Databasetable(tablename = "test1")public class Test1 {    @ForeignCollectionFIEld    private ForeignCollection<Test2> test2Collection;}@Databasetable(tablename = "test2")public class Test2 {    @ForeignCollectionFIEld    private ForeignCollection<Test1> test1Collection;}

我面临的问题是在创建表时使用Ormlite,不知道此类之间的外键.

为了建立这种关系,我必须像这样在每个类上添加一个ForeignDatabaseFIEld：

@Databasetable(tablename = "test1")public class Test1 {    @DatabaseFIEld(foreign = true, foreignautoRefresh = true)    private Test2 test2;    @ForeignCollectionFIEld    private ForeignCollection<Test2> test2Collection;}@Databasetable(tablename = "test2")public class Test2 {    @DatabaseFIEld(foreign = true, foreignautoRefresh = true)    private Test1 test1;    @ForeignCollectionFIEld    private ForeignCollection<Test1> test2Collection;}

这似乎是一种奇怪的方式？

解决方法:

In order to make this relation do I have to add a single ForeignDatabaseFIEld on each class like that:

对于多对多关系,将对象关联在一起的最佳方法是使用“联接表”.在您的情况下,将有一个名为Test1Test2Join的第三个表.

@Databasetable(tablename = "test1test2join")public class Test1Test2Join {    @DatabaseFIEld(generatedID = true)    private long ID;    @DatabaseFIEld(foreign = true)    private Test1 test1;    @DatabaseFIEld(foreign = true)    private Test test2;}

有关更多信息,请参见many-to-many example.

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