I have 2 classes:
public class Car {
private Integer id;
private List<CarOrder> carOrders;
}
public class CarOrder {
private Car car;
private Long endDate;
private Long id;
}
and hibernate mapping
<class entity-name="car" name="test.es.Car" table="CARS" schema="ARK_ES">
<cache usage="read-write"/>
<id name="id" column="ID">
<generator class="sequence">
<param name="sequence">ES_SEQUENCE</param>
</generator>
</id>
<bag name="carOrders" inverse="true" lazy="true">
<cache usage="read-write"/>
<key column="CAR_ID"/>
<one-to-many not-found="ignore" entity-name="carOrder"/>
</bag>
</class>
<class entity-name="carOrder" name="temp.es.CarOrder" table="CAR_ORDERS" schema="ARK_ES">
<cache usage="read-write"/>
<id name="id" column="ID">
<generator class="sequence">
<param name="sequence">ES_ORDER_SEQUENCE</param>
</generator>
</id>
<property name="endDate" column="END_DATE"/>
<many-to-one name="car" entity-name="car">
<column name="CAR_ID"/>
</many-to-one>
</class>
I need to load all cars and car orders with endDate greater than some value. Also i need to cache the query for car order. i tried to use hibernate filters, but they are not cached. Is it possible to achieve this using hibernate api without custom queries?
I forgot to mention that car can have no orders, but it must be in result.
Thanks.
So you can use the #fitler and #filterdef annotation on your collection class. But then it is very important to enable the filters in the session. Please follow this link on how to enable filters, they are not enabled by default.
How to enable hibernate filter for sessionFactory.getCurrentSession()?
Related
I have two objets like:
public class Object1 implements Serializable {
protected Integer id; // This is the PK in the xml mapping
protected Integer otherId;
}
public class Object2 implements Serializable {
protected Integer id; // This is the PK in the xml mapping
protected Set<Object1> object1List; // I want to relate this set against the "otherId" attribute
}
And I have this hibernate XML mappings:
<class name="Object1" table="Object1Table">
<id name="id" type="java.lang.Integer">
<column name="id" />
<generator class="identity" />
</id>
<property name="otherId" type="java.lang.Integer">
<column name="other_id"></column>
</property>
</class>
<class name="Object2" table="Object2Table">
<id name="id" type="java.lang.Integer">
<column name="id" />
<generator class="identity" />
</id>
<set name="object1List" table="Object1Table" lazy="false" fetch="join" >
<key column="other_id" /> // This is not working
<one-to-many class="Object1" />
</set>
</class>
But I don't know how to relate the "set" mapping against the "other_id" attribute, it only works against the PK "id" of the "Object1" table.
Does anyone know how to solve this situation?
I think you need to mark the <set as inverse. Like crizzis mentioned, you'd be better off if you use the annotation model. A lot more people can help you with the annotation model. Apart from that, the HBM XML mapping will be replaced with the JPA orm.xml mapping at some point, so I wouldn't use that approach anymore.
I'm adding ResourcePermission to the object Report. Each Query object can have in a one-to-one relationship. A Query extends Resource and has ResourcePermission's in a one-to-many (one Query to many Permissions).
I need to add the same property to the Report object associated with the Query because it can have different permissions. When I add the list and the map the one Query to many Permission relationship I get
Caused by: org.hibernate.MappingException: Repeated column in mapping for entity: com.bio.ResourcePermission column: resource_id (should be mapped with insert="false" update="false")
Which I am not understanding why, the Report does not extend Query or Resource and therefore it isn't mapped twice. Can a table just not be the many for multiple one-to-many relationships?
<class name="com.bio.Report" table="REPORT">
<id name="id" type="long" column="id">
<generator class="foreign">
<param name="property">query</param>
</generator>
</id>
<property name="name" column="name"/>
<!--Trying to add this list mapping breaks it-->
<bag name="permissions" table="RESOURCE_PERMISSION">
<key column="resource_id" not-null="true"/>
<one-to-many class="com.bio.ResourcePermission"/>
</bag>
<!-- This query extends Resource-->
<one-to-one name="query" class="com.bio.Query" />
</class>
This is the original item that had ResourcePermissions
<class name="com.bio.Resource" table="RESOURCE">
<id name="id" type="long" column="id">
<generator class="native">
<param name="sequence">SEQ_RESOURCE_AUTO</param>
</generator>
</id>
<bag name="permissions" table="RESOURCE_PERMISSION" lazy="true" batch-size="50" cascade="all-delete-orphan">
<key column="resource_id" not-null="true"/>
<one-to-many class="com.bio.ResourcePermission"/>
</bag>
</class>
The Permission mapping
<class name="com.bio.ResourcePermission" table="RESOURCE_PERMISSION">
<id name="id" type="long" column="id">
<generator class="native">
<param name="sequence">SEQ_RES_PERM_AUTO</param>
</generator>
</id>
<property name="canEdit" column="edit"/>
<property name="canView" column="can_view"/>
<property name="canRun" column="run"/>
<property name="everyone" column="everyone"/>
</class>
I had to set inverse="true" on the Report mapping since the ReportPermission will be responsible for the relationship.
<bag name="permissions" table="RESOURCE_PERMISSION" inverse="true">
<key column="resource_id" not-null="true"/>
<one-to-many class="com.bio.ResourcePermission"/>
</bag>
I have many Model Entities like
class Employee {
private Integer id;
private String name;
}
class Address {
private Integer id;
private String address;
}
and many more..
Can we map all Entities together in single hbm xml mapping file?
I know it might not be good practice. but Still can we do it? If yes then how ?
Yes. It is possible to use a single mapping file.
Something like this:
<hibernate-mapping>
<class name="Employee" table="employee">
<id name="id" type="java.lang.Integer">
<column name="id"/>
<generator class="native"/>
</id>
<property name="name" type="java.lang.String">
<column name="name"/>
</property>
</class>
<class name="Address" table="address">
<id name="id" type="java.lang.Integer">
<column name="id"/>
<generator class="native"/>
</id>
<property name="address" type="java.lang.String">
<column name="address"></column>
</property>
</class>
</hibernate-mapping>
Yes you can do this, the dtd (http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd) allows multiple class elements in hibernate-mapping:
<!ELEMENT hibernate-mapping (
...
(class|subclass|joined-subclass|union-subclass)*,
...
)>
Even the documentation (http://docs.jboss.org/hibernate/orm/4.3/manual/en-US/html/ch05.html#mapping-declaration, second code block) maps as an example a Cat and a Dog class in the same file.
I have a table Project with fields
ID
PROJECT_BASELINE_ATTRIBUTES_ID (FK for table PROJECT_BASELINE_ATTR)
This table has the following mapping
<hibernate-mapping package="com.initech.db.model">
<class name="com.initech.db.model.Project" table="PROJECT">
<id name="id" column="id" type="java.lang.Long">
<meta attribute="use-in-tostring">true</meta>
<generator class="sequence">
<param name="sequence">PROJECT_ID_SEQ</param>
</generator>
</id>
<many-to-one name="projectBaselineAttributes" column="PROJECT_BASELINE_ATTRIBUTES_ID" class="com.initech.db.model.ProjectBaselineAttributes" cascade="all" not-null="true">
<meta attribute="use-in-tostring">true</meta>
</many-to-one>^
</class>
</hibernate-mapping>
The respective Project.java class has the fields
private Long id;
private ProjectBaselineAttributes projectBaselineAttributes;
Furthermore, I have a table PROJECT_BASELINE_ATTR, containing the field
ID
The Hibernate mapping:
<hibernate-mapping package="com.initech.db.model">
<class name="com.initech.db.model.ProjectBaselineAttributes" table="PROJECT_BASELINE_ATTR">
<id name="id" column="id" type="java.lang.Long">
<generator class="sequence">
<param name="sequence">PRO_BASE_ATTR_ID_SEQ</param>
</generator>
</id>
<set name="projects" table="PROJECT" inverse="true" lazy="true" fetch="select">
<key>
<column name="PROJECT_BASELINE_ATTRIBUTES_ID" precision="22" scale="0" not-null="true" />
</key>
<one-to-many class="com.initech.db.model.Project" />
</set>
</class>
</hibernate-mapping>
The respective ProjectBaselineAttributes.java class has the fields
private Long id;
private Set projects = new HashSet();
The current mapping is not ideal, as the relationship between the two tables is actually one-to-one, but in the ProjectBaselineAttributes I have a set of Projects, even though there is always one Projet for one ProjectBaseLineattributes. What should the mapping look like for ProjectBaselineAttributes so that I can get the associated Project "singularly", i.e. so that the class ProjectBaselineAttributes.java would look like this:
private Long id;
private Project project;
Here's the section of the Hibernate documentation which details how to map such a bidirectional one-to-one association using a foreign key.
<class name="Person">
<id name="id" column="personId">
<generator class="native"/>
</id>
<many-to-one name="address"
column="addressId"
unique="true"
not-null="true"/>
</class>
<class name="Address">
<id name="id" column="addressId">
<generator class="native"/>
</id>
<one-to-one name="person"
property-ref="address"/>
</class>
create table Person ( personId bigint not null primary key, addressId bigint not null unique )
create table Address ( addressId bigint not null primary key )
You can try the below mappings as told in this example.
In the parent bean,
<one-to-one name="one2oneSubA1" class="com.manu.hibernate.mappings.domain.ASub1" cascade="all"
property-ref="parent"/>
In the child bean,
<many-to-one name="parent"
class="com.manu.hibernate.mappings.domain.AMain" column="a_id"
unique="true" cascade="save-update" />
I'm sure there must be thousands of examples demonstrating this association but I can't seem to find one anywhere.
I have a one-many relationship from Parent-Child and a many-one relationship from Child-Parent:
class Parent {
private Long id;
private String name;
private List<Child> children;
}
class Child {
private Long id;
private String name;
private Parent parent;
}
I'm expecting to end up with 2 tables that look as follows:
Parent
- id : bigint
- name : varchar
Child
- id : bigint
- parent_id : bigint
- sequence : bigint
- name : varchar
Have I got the right idea? If so does anyone know what I need to put in my mapping file so that when a parent is deleted so too are it's children.
Thanks in advance.
James
Found the solution in the end although I don't understand why I need insert="false" and update="false":
<hibernate-mapping>
<class name="foo.Parent" table="Parent">
<id name="id" type="int" column="id">
<generator class="native" />
</id>
<property name="name" type="java.lang.String" column="name" length="50" />
<list name="children" cascade="all">
<key column="parent_id" />
<index column="sequence" />
<one-to-many class="foo.Child" />
</list>
</class>
<class name="foo.Child" table="Child">
<id name="id" type="int" column="id">
<generator class="native" />
</id>
<property name="name" type="java.lang.String" column="name" length="50" />
<many-to-one name="parent" class="foo.Parent" column="parent_id" insert="false" update="false" />
</class>
</hibernate-mapping>