Customer.java
public class Customer {
public Customer() {
super();
// TODO Auto-generated constructor stub
}
public Customer(String cust_name, String cust_source) {
super();
this.cust_name = cust_name;
this.cust_source = cust_source;
}
private Long cust_id;
private String cust_name;
private String cust_source;
private String cust_industry;
private String cust_level;
private String cust_phone;
private String cust_mobile;
//Represented by ORM: multiple contacts corresponding to a customer
//A collection of multiple prevented parties. Hibernate uses Set sets by default
private Set<LinkMan> linkMans=new HashSet<LinkMan>();
//Omit get and set methods
}LinkMan.java
public class LinkMan {
private Long lkm_id;
private String lkm_name;
private String lkm_gender;
private String lkm_phone;
private String lkm_mobile;
private String lkm_email;
private String lkm_qq;
private String lkm_position;
private String lkm_memo;
//By ORM: a contact can only belong to one customer
//Objects placed on one side
private Customer customer;
//Omit get and set methods
}Customer.hbm.xml
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-mapping PUBLIC
"-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd">
<hibernate-mapping>
<class name="com.hibernate.domain.Customer" table="cst_customer">
<! -- create OID and primary key mapping -- >
<id name="cust_id" column="cust_id">
<generator class="native"/>
</id>
<! -- establish correspondence between common properties and fields in the table -- >
<property name="cust_name" column="cust_name"/>
<property name="cust_source" column="cust_source"/>
<property name="cust_industry" column="cust_industry"/>
<property name="cust_level" column="cust_level"/>
<property name="cust_phone" column="cust_phone"/>
<property name="cust_mobile" column="cust_mobile"/>
<! -- configure one to many mapping: a set of placed many sides -- >
<!--
set Tags
*Name: the attribute name of the object collection of multiple parties
*Cascade: cascade
*inverse: give up the maintenance right of foreign key default false: do not give up
-->
<set name="linkMans">
<!--
key Tags
*column: the name of the foreign key of more than one party
-->
<key column="lkm_cust_id"/>
<!--
One to many label
*class: the full path of multiple parties
-->
<one-to-many class="com.hibernate.domain.LinkMan"/>
</set>
</class>
</hibernate-mapping>LinkMan.hbm.xml
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-mapping PUBLIC
"-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd">
<hibernate-mapping>
<class name="com.hibernate.domain.LinkMan" table="cst_linkman">
<! -- create OID and primary key mapping -- >
<id name="lkm_id" column="lkm_id">
<generator class="native"/>
</id>
<! -- create mapping between common attributes and table fields -- >
<property name="lkm_name"/>
<property name="lkm_gender"/>
<property name="lkm_phone"/>
<property name="lkm_mobile"/>
<property name="lkm_email"/>
<property name="lkm_qq"/>
<property name="lkm_position"/>
<property name="lkm_memo"/>
<! -- configure many to one relationship: objects placed on one side -- >
<!--
Many to one tag
*Name: property name of one party's object
*class: the full path of one party
*column: the name of the foreign key of the table on more than one side
-->
<many-to-one name="customer" cascade="save-update,delete" class="com.hibernate.domain.Customer" column="lkm_cust_id"/>
</class>
</hibernate-mapping>
HibernateUtils.java
public class HibernateUtils {
public static final Configuration cfg;
public static final SessionFactory sf;
static{
cfg = new Configuration().configure();
sf = cfg.buildSessionFactory();
}
public static Session openSession(){
return sf.openSession();
}
public static Session getCurrentSession() {
return sf.getCurrentSession();//Need configuration
}
}hibernate.cfg.xml under src
<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE hibernate-configuration PUBLIC "-//Hibernate/Hibernate Configuration DTD 3.0//EN" "http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd"> <hibernate-configuration> <session-factory> <!-- Basic parameters of connecting database --> <!-- hibernate-release-5.0.7.Final\project\etc\hibernate.properties --> <!-- localhost:3306 --> <property name="hibernate.connection.driver_class">com.mysql.jdbc.Driver</property> <property name="hibernate.connection.url">jdbc:mysql:///hibernate_day04</property> <property name="hibernate.connection.username">root</property> <property name="hibernate.connection.password">password</property> <!-- To configure Hibernate Dialect --> <property name="hibernate.dialect">org.hibernate.dialect.MySQLDialect</property> <!-- ==========Optional configuration========= --> <!-- Printing sql --> <property name="hibernate.show_sql">true</property> <!-- Format sql --> <property name="hibernate.format_sql">true</property> <!-- Automatic table building create update --> <property name="hibernate.hbm2ddl.auto">update</property> <!-- Set transaction isolation level --> <!-- 1 read uncommitted :Dirty reading, non repeatable reading and virtual reading all happen 2 read committed :Solve dirty reading (oracle default) 4 repeatable read :Solving dirty and non repeatable reading(mysql default) 8 serializable :Solve all problems. Serial execution, low efficiency --> <property name="hibernate.connection.isolation">4</property> <!-- Configure the Session --> <!-- No need session.close() --> <property name="hibernate.current_session_context_class">thread</property> <!-- Introducing mapping --> <mapping resource="com/hibernate/domain/Customer.hbm.xml"/> <mapping resource="com/hibernate/domain/LinkMan.hbm.xml"/> </session-factory> </hibernate-configuration>
Test class
import java.util.List;
import org.hibernate.Criteria;
import org.hibernate.Session;
import org.hibernate.Transaction;
import org.hibernate.criterion.DetachedCriteria;
import org.hibernate.criterion.Order;
import org.hibernate.criterion.Projections;
import org.hibernate.criterion.Restrictions;
import org.junit.Test;
import com.hibernate.domain.Customer;
import com.hibernate.domain.LinkMan;
import com.hibernate.utils.HibernateUtils;
/**
* QBC Queries
* @author zhang
*
*/
public class HibernateDemo2 {
@Test
/**
* Simple query
*/
public void demo1() {
Session session=HibernateUtils.getCurrentSession();
Transaction tx=session.beginTransaction();
//Get the object of Criteria
Criteria criteria = session.createCriteria(Customer.class);
List<Customer> list=criteria.list();
for (Customer customer : list) {
System.out.println(customer);
}
tx.commit();
}
@Test
/**
* Sort query
*/
public void demo2() {
Session session=HibernateUtils.getCurrentSession();
Transaction tx=session.beginTransaction();
//Sort query
Criteria criteria = session.createCriteria(Customer.class);
// Criteria. Addorder (order. ASC ("cust" ID)); / / ascending
criteria.addOrder(Order.desc("cust_id"));
List<Customer> list=criteria.list();
for (Customer customer : list) {
System.out.println(customer);
}
tx.commit();
}
@Test
/**
* Paging query
*/
public void demo3() {
Session session=HibernateUtils.getCurrentSession();
Transaction tx=session.beginTransaction();
//Paging query
Criteria criteria = session.createCriteria(LinkMan.class);
criteria.setFirstResult(10);
criteria.setMaxResults(10);
List<LinkMan> list = criteria.list();
for (LinkMan linkMan : list) {
System.out.println(linkMan);
}
tx.commit();
}
@Test
/**
* Conditional query
*/
public void demo4() {
Session session=HibernateUtils.getCurrentSession();
Transaction tx=session.beginTransaction();
//Conditional query
Criteria criteria = session.createCriteria(Customer.class);
//Setting conditions
/**
* == eq
* > gt
* >= ge
* < lt
* <= le
* <> ne
* like
* in
* and
* or
*/
criteria.add(Restrictions.eq("cust_source", "Computer"));
// Criteria. Add (restrictions. Or (restrictions. Like ("cust'u name", "Li%"));
criteria.add(Restrictions.like("cust_name", "Plum%"));//Juxtaposition of two conditions
List<Customer> list = criteria.list();
for (Customer customer : list) {
System.out.println(customer);
}
tx.commit();
}
@Test
//Statistical query
public void demo5() {
Session session=HibernateUtils.getCurrentSession();
Transaction tx=session.beginTransaction();
Criteria criteria = session.createCriteria(Customer.class);
/**
* add :Common condition
* addOrder :sort
* setProjection :Aggregate function and group by having
*/
criteria.setProjection(Projections.rowCount());
// Object object = criteria.uniqueResult();
Long num=(Long) criteria.uniqueResult();
System.out.println(num);
tx.commit();
}
@Test
/**
* Offline condition query
*/
public void demo6() {
//web level
DetachedCriteria detachedCriteria=DetachedCriteria.forClass(Customer.class);
detachedCriteria.add(Restrictions.like("cust_name", "Plum%"));
//dao level
Session session=HibernateUtils.getCurrentSession();
Transaction transaction=session.beginTransaction();
Criteria criteria = detachedCriteria.getExecutableCriteria(session);
List<Customer> list = criteria.list();
for (Customer customer : list) {
System.out.println(customer);
}
transaction.commit();
}
}
If you feel like this query, it has a big gap with SQL and is more inclined to object-oriented.