Hibernate video learning notes (10) Other Mappings

ComponentIng

 

InHibernateMedium, ComponentIs the logical component of an object,The fundamental difference between it and entity is that there is noOid,

ComponentCan be a value object (Ddd)

 

UseComponentBenefits of ing: it achieves fine-grained division of object models, with more distinct layers and higher reuse rates.

<Class name = "com. bjsxt. hibernate. User" table = "t_user">

<ID name = "ID">

<Generator class = "native"/>

</ID>

<Property name = "name"/>

<Component name = "Contact">

<Property name = "email"/>

<Property name = "Address"/>

<Property name = "zipcode"/>

<Property name = "contacttel"/>

</Component>

</Class>

 

The corresponding table is stillUserTable is only an object strength subdivision

 

User user = new user ();

User. setname ("Zhang San");

Contact contact = new contact ();

Contact. setaddress ("XXXXX ");

Contact. setemail ("xxx@rrr.com ");

Contact. setzipcode ("1111111 ");

Contact. setcontacttel ("9999999999 ");

User. setcontact (contact );

Session. Save (User );

 

Composite primary key ing

Composite (union) primary key ing

 

Generally, attributes related to the composite primary key are put into a class separately.

*This class must implement the serialization Interface

*OverwriteHashcodeAndEqualsMethod

 

Public class fiscalyearperiodpk implements serializable {

 

//Accounting Year

Private int fiscalyear;

//Monthly accounting

Private int fiscalperiod;

 

Public int getfiscalyear (){

Return fiscalyear;

}

 

Public void setfiscalyear (INT fiscalyear ){

This. fiscalyear = fiscalyear;

}

 

Public int getfiscalperiod (){

Return fiscalperiod;

}

 

Public void setfiscalperiod (INT fiscalperiod ){

This. fiscalperiod = fiscalperiod;

}

 

@ Override

Public int hashcode (){

Final int prime = 31;

Int result = 1;

Result = prime * result + fiscalperiod;

Result = prime * result + fiscalyear;

Return result;

}

 

@ Override

Public Boolean equals (Object OBJ ){

If (this = OBJ)

Return true;

If (OBJ = NULL)

Return false;

If (getclass ()! = Obj. getclass ())

Return false;

Final fiscalyearperiodpk Other = (fiscalyearperiodpk) OBJ;

If (fiscalperiod! = Other. fiscalperiod)

Return false;

If (fiscalyear! = Other. fiscalyear)

Return false;

Return true;

}

}

 

<Class name = "com. bjsxt. hibernate. fiscalyearperiod" table = "t_fiscal_year_period">

<Composite-ID name = "fiscalyearperiodpk">

<Key-property name = "fiscalyear"/>

<Key-property name = "fiscalperiod"/>

</Composite-ID>

<Property name = "begindate"/>

<Property name = "enddate"/>

<Property name = "periodsts"/>

</Class>

 

In the inheritance ing, ifClassOfAbstractAttributeTrueNo table is generated.

 

Set

List

Array

Map

T_collectionmapping

id	name
1	Xxx

 

T_set_values

set_id	set_value
1	A
1	B

 

T_list_value

list_id	list_value	list_index
1	C	0
1	D	1

 

T_array_value

array_id	array_value	array_index
1	E	0
1	F	1

 

T_map_value

map_id	map_key	map_value
1	k1	V1
1	K2	V2

 

<ID name = "ID">

<Generator class = "native"/>

</ID>

<Property name = "name"/>

<Set name = "setvalue" table = "t_set_value">

<Key column = "set_id"/>

<Element type = "string" column = "set_value"/>

</Set>

<List name = "listvalue" table = "t_list_value">

<Key column = "list_id"/>

<List-index column = "list_index"/> //To save order

<Element type = "string" column = "list_value"/>

</List>

<Array name = "arrayvalue" table = "t_array_value">

<Key column = "array_id"/>

<List-index column = "array_index"/>

<Element type = "string" column = "array_value"/>

</Array>

<Map Name = "mapvalue" table = "t_map_value">

<Key column = "map_id"/>

<Map-Key type = "string" column = "map_key"/>

<Element type = "string" column = "map_value"/>

</Map>