Admin: 1 версия

2010-06-01T06:51:30Z

1 версия

в 18:01, 31 мая 2010

2010-05-31T18:01:45Z

Новая страница

== Collection Mapping: Many-To-Many map based on HashMap ==



<source lang="java">
/////////////////////////////////////////////////////////////////////////
public class Benefit {
private int id;
private int cost;
public Benefit() {
}
public Benefit(int c) {
cost = c;
}
public void setId(int i) {
id = i;
}
public int getId() {
return id;
}
public void setCost(int i) {
cost = i;
}
public int getCost() {
return cost;
}
}
/////////////////////////////////////////////////////////////////////////
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-mapping
PUBLIC "-//Hibernate/Hibernate Mapping DTD//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-2.0.dtd">
<hibernate-mapping>
<class name="Employee" table="employee">
<id name="id" unsaved-value="0">
<generator class="increment"/>
</id>

<map name="benefits" table="employee_benefit" cascade="all">
<key column="parent_id"/>
<index column="benefit_name" type="string"/>
<many-to-many column="benefit_id" class="Benefit"/>
</map>
<property name="name" type="string"/>
</class>
<class name="Benefit" table="benefit">
<id name="id" unsaved-value="0">
<generator class="increment"/>
</id>
<property name="cost" type="int"/>
</class>
</hibernate-mapping>

/////////////////////////////////////////////////////////////////////////

import java.util.*;
public class Employee {
private int id;
private String name;
private Map benefits;
public Employee() {
}
public void setId(int i) {
id = i;
}
public int getId() {
return id;
}
public void setName(String s) {
name = s;
}
public String getName() {
return name;
}
public void setBenefits(Map m) {
benefits = m;
}

public Map getBenefits() {
return benefits;
}
}
/////////////////////////////////////////////////////////////////////////

<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE hibernate-configuration PUBLIC
"-//Hibernate/Hibernate Configuration DTD//EN"
"http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd">
<hibernate-configuration>
<session-factory>

<property name="connection.driver_class">org.hsqldb.jdbcDriver</property>
<property name="connection.url">jdbc:hsqldb:data/tutorial</property>
<property name="connection.username">sa</property>
<property name="connection.password"></property>

<property name="connection.pool_size">1</property>

<property name="dialect">org.hibernate.dialect.HSQLDialect</property>

<property name="show_sql">true</property>

<mapping resource="Employee.hbm.xml"/>
</session-factory>
</hibernate-configuration>
/////////////////////////////////////////////////////////////////////////
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.Statement;
import java.sql.ResultSet;
import java.sql.ResultSetMetaData;
import org.hibernate.HibernateException;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.cfg.Configuration;
public class HibernateUtil {
public static final SessionFactory sessionFactory;
static {
try {
// Create the SessionFactory from hibernate.cfg.xml
sessionFactory = new Configuration().configure().buildSessionFactory();
} catch (Throwable ex) {
// Make sure you log the exception, as it might be swallowed
System.err.println("Initial SessionFactory creation failed." + ex);
throw new ExceptionInInitializerError(ex);
}
}
public static final ThreadLocal session = new ThreadLocal();
public static Session currentSession() throws HibernateException {
Session s = (Session) session.get();
// Open a new Session, if this thread has none yet
if (s == null) {
s = sessionFactory.openSession();
// Store it in the ThreadLocal variable
session.set(s);
}
return s;
}
public static void closeSession() throws HibernateException {
Session s = (Session) session.get();
if (s != null)
s.close();
session.set(null);
}

static Connection conn;
static Statement st;
public static void setup(String sql) {
try {
// Step 1: Load the JDBC driver.
Class.forName("org.hsqldb.jdbcDriver");
System.out.println("Driver Loaded.");
// Step 2: Establish the connection to the database.
String url = "jdbc:hsqldb:data/tutorial";
conn = DriverManager.getConnection(url, "sa", "");
System.out.println("Got Connection.");
st = conn.createStatement();
st.executeUpdate(sql);
} catch (Exception e) {
System.err.println("Got an exception! ");
e.printStackTrace();
System.exit(0);
}
}
public static void checkData(String sql) {
try {
HibernateUtil.outputResultSet(st
.executeQuery(sql));
// conn.close();
} catch (Exception e) {
e.printStackTrace();
}
}
public static void outputResultSet(ResultSet rs) throws Exception{
ResultSetMetaData metadata = rs.getMetaData();
int numcols = metadata.getColumnCount();
String[] labels = new String[numcols];
int[] colwidths = new int[numcols];
int[] colpos = new int[numcols];
int linewidth;
for (int i = 0; i < numcols; i++) {
labels[i] = metadata.getColumnLabel(i + 1); // get its label
System.out.print(labels[i]+" ");
}
System.out.println("------------------------");
while (rs.next()) {
for (int i = 0; i < numcols; i++) {
Object value = rs.getObject(i + 1);
if(value == null){
System.out.print(" ");
}else{
System.out.print(value.toString().trim()+" ");
}

}
System.out.println(" ");
}
}
}

/////////////////////////////////////////////////////////////////////////
import java.io.Serializable;
import java.util.*;
import org.hibernate.*;
import org.hibernate.cfg.*;
import org.hibernate.criterion.*;
import org.hibernate.event.*;
import org.hibernate.event.def.*;
public class Main {
public static void main(String[] args) throws Exception {
HibernateUtil.setup("create table employee (id int,name varchar);");
HibernateUtil.setup("create table benefit (id int,cost int);");
HibernateUtil.setup("create table employee_benefit (parent_id int,benefit_name varchar,benefit_id int);");

Session session = HibernateUtil.currentSession();
Employee sp = new Employee();
Employee sp3 = new Employee();

sp.setName("Joe");
HashMap p = new HashMap();
p.put("health", new Benefit(200));
p.put("dental", new Benefit(300));
sp.setBenefits(p);
sp3.setName("Jim");
sp3.setBenefits(p);
session.save(sp);
session.save(sp3);
session.flush();
HibernateUtil.closeSession();
session = HibernateUtil.currentSession();
Employee sp2 = (Employee)session.load(Employee.class, new Integer(sp.getId()));
Map p2 = sp2.getBenefits();
System.out.println(((Benefit)p2.get("health")).getCost());
System.out.println(((Benefit)p2.get("dental")).getCost());

session.flush();
session.close();
HibernateUtil.checkData("select * from employee");
HibernateUtil.checkData("select * from benefit");
HibernateUtil.checkData("select * from employee_benefit");
}
}

</source>



== Many To Many Map Cascade Load ==



<source lang="java">
/////////////////////////////////////////////////////////////////////////
import java.util.*;
import org.hibernate.*;
import org.hibernate.criterion.*;
public class SimpleRetrieveTest {

public static void main(String[] args) {
HibernateUtil.setup("create table m_EVENTS ( uid int, name VARCHAR, start_Date date, duration int, location_id int);");
HibernateUtil.setup("create table m_speakers ( uid int, firstName VARCHAR, lastName VARCHAR);");
HibernateUtil.setup("create table event_speakers (elt int, event_id int, speaker_id int);");

// hibernate code start
Session session = HibernateUtil.currentSession();
Transaction tx = session.beginTransaction();

EventManyToMany event = new EventManyToMany();
event.setName("Inverse test");
event.setSpeakers(new HashSet());
event.getSpeakers().add(new SpeakerManyToMany("John", "Smith", event));
event.getSpeakers().add(new SpeakerManyToMany("Dave", "Smith", event));
event.getSpeakers().add(new SpeakerManyToMany("Joan", "Smith", event));

session.save(event);

event = (EventManyToMany) session.load(EventManyToMany.class, event.getId());
Set speakers = event.getSpeakers();
for (Iterator i = speakers.iterator(); i.hasNext();) {
SpeakerManyToMany speaker = (SpeakerManyToMany) i.next();
System.out.println(speaker.getFirstName());
System.out.println(speaker.getLastName());
System.out.println(speaker.getId());
}

tx.rumit();
HibernateUtil.closeSession();
HibernateUtil.sessionFactory.close();
HibernateUtil.checkData("select * from m_speakers");
HibernateUtil.checkData("select uid, name from m_events");
// hibernate code end
}

}

/////////////////////////////////////////////////////////////////////////
<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC
"-//Hibernate/Hibernate Mapping DTD 2.0//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-2.0.dtd">
<hibernate-mapping>
<class name="SpeakerManyToMany" table="m_speakers">
<id name="id" column="uid" type="long">
<generator class="increment"/>
</id>
<property name="firstName" type="string" length="20"/>
<property name="lastName" type="string" length="20"/>
<set name="events" table="event_speakers" cascade="all">
<key column="speaker_id"/>
<many-to-many class="EventManyToMany"/>
</set>
</class>
</hibernate-mapping>

/////////////////////////////////////////////////////////////////////////
import java.util.Set;
import java.util.HashSet;
public class SpeakerManyToMany {
private Long id;
private String firstName;
private String lastName;
private Set events;
public SpeakerManyToMany() {
}
public SpeakerManyToMany(String firstName, String lastName) {
setFirstName(firstName);
setLastName(lastName);
}
public SpeakerManyToMany(String firstName, String lastName, EventManyToMany event) {
this(firstName, lastName);
addEvent(event);
}
public Long getId() {
return id;
}
public void setId(Long id) {
this.id = id;
}
public String getFirstName() {
return firstName;
}
public void setFirstName(String firstName) {
this.firstName = firstName;
}
public String getLastName() {
return lastName;
}
public void setLastName(String lastName) {
this.lastName = lastName;
}
public Set getEvents() {
return this.events;
}
public void setEvents(Set events) {
this.events = events;
}
private void addEvent(EventManyToMany event) {
if (events == null) {
events = new HashSet();
}
events.add(event);
}
}

/////////////////////////////////////////////////////////////////////////
import java.util.Date;
import java.util.Set;
public class EventManyToMany {
private Long id;
private String name;
private Date startDate;
private int duration;
private Set speakers;
private Set attendees;
private LocationManyToMany location;
public void setId(Long id) {
this.id = id;
}

public Long getId() {
return id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public Date getStartDate() {
return startDate;
}
public void setStartDate(Date startDate) {
this.startDate = startDate;
}
public int getDuration() {
return duration;
}
public void setDuration(int duration) {
this.duration = duration;
}
public LocationManyToMany getLocation() {
return location;
}
public void setLocation(LocationManyToMany location) {
this.location = location;
}
public void setSpeakers(Set speakers) {
this.speakers = speakers;
}

public Set getSpeakers() {
return speakers;
}
public Set getAttendees() {
return attendees;
}
public void setAttendees(Set attendees) {
this.attendees = attendees;
}
}

/////////////////////////////////////////////////////////////////////////
<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC
"-//Hibernate/Hibernate Mapping DTD 2.0//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-2.0.dtd">
<hibernate-mapping>
<class name="EventManyToMany" table="m_events">
<id name="id" column="uid" type="long" unsaved-value="null">
<generator class="increment"/>
</id>
<property name="name" type="string" length="100"/>
<property name="startDate" column="start_date"
type="date"/>
<property name="duration" type="integer"/>
<many-to-one name="location" column="location_id"
class="LocationManyToMany"/>
<set name="speakers" table="event_speakers" cascade="all">
<key column="event_id"/>
<many-to-many class="SpeakerManyToMany"/>
</set>
</class>
</hibernate-mapping>

/////////////////////////////////////////////////////////////////////////
<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE hibernate-configuration PUBLIC
"-//Hibernate/Hibernate Configuration DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd">
<hibernate-configuration>
<session-factory>

<property name="connection.driver_class">org.hsqldb.jdbcDriver</property>
<property name="connection.url">jdbc:hsqldb:data/tutorial</property>
<property name="connection.username">sa</property>
<property name="connection.password"></property>

<property name="connection.pool_size">1</property>

<property name="dialect">org.hibernate.dialect.HSQLDialect</property>

<property name="show_sql">true</property>
<mapping resource="EventManyToMany.hbm.xml"/>
<mapping resource="SpeakerManyToMany.hbm.xml"/>
<mapping resource="LocationManyToMany.hbm.xml"/>
</session-factory>
</hibernate-configuration>

</source>



== Many to Many Map Cascade Save ==



<source lang="java">
/////////////////////////////////////////////////////////////////////////

import java.util.*;
import org.hibernate.*;
import org.hibernate.criterion.*;
public class SimpleRetrieveTest {

public static void main(String[] args) {
HibernateUtil.setup("create table m_EVENTS ( uid int, name VARCHAR, start_Date date, duration int, location_id int);");
HibernateUtil.setup("create table m_speakers ( uid int, firstName VARCHAR, lastName VARCHAR);");
HibernateUtil.setup("create table event_speakers (elt int, event_id int, speaker_id int);");

// hibernate code start
Session session = HibernateUtil.currentSession();
Transaction tx = session.beginTransaction();

EventManyToMany event = new EventManyToMany();
event.setName("Inverse test");
event.setSpeakers(new HashSet());
event.getSpeakers().add(new SpeakerManyToMany("John", "Smith", event));
event.getSpeakers().add(new SpeakerManyToMany("Dave", "Smith", event));
event.getSpeakers().add(new SpeakerManyToMany("Joan", "Smith", event));

session.save(event);

tx.rumit();
HibernateUtil.closeSession();
HibernateUtil.sessionFactory.close();
HibernateUtil.checkData("select * from m_speakers");
HibernateUtil.checkData("select uid, name from m_events");
// hibernate code end
}

}

/////////////////////////////////////////////////////////////////////////
<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC
"-//Hibernate/Hibernate Mapping DTD 2.0//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-2.0.dtd">
<hibernate-mapping>
<class name="EventManyToMany" table="m_events">
<id name="id" column="uid" type="long" unsaved-value="null">
<generator class="increment"/>
</id>
<property name="name" type="string" length="100"/>
<property name="startDate" column="start_date"
type="date"/>
<property name="duration" type="integer"/>
<many-to-one name="location" column="location_id"
class="LocationManyToMany"/>
<set name="speakers" table="event_speakers" cascade="all">
<key column="event_id"/>
<many-to-many class="SpeakerManyToMany"/>
</set>
</class>
</hibernate-mapping>

/////////////////////////////////////////////////////////////////////////
import java.util.Date;
import java.util.Set;
public class EventManyToMany {
private Long id;
private String name;
private Date startDate;
private int duration;
private Set speakers;
private Set attendees;
private LocationManyToMany location;
public void setId(Long id) {
this.id = id;
}

public Long getId() {
return id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public Date getStartDate() {
return startDate;
}
public void setStartDate(Date startDate) {
this.startDate = startDate;
}
public int getDuration() {
return duration;
}
public void setDuration(int duration) {
this.duration = duration;
}
public LocationManyToMany getLocation() {
return location;
}
public void setLocation(LocationManyToMany location) {
this.location = location;
}
public void setSpeakers(Set speakers) {
this.speakers = speakers;
}

public Set getSpeakers() {
return speakers;
}
public Set getAttendees() {
return attendees;
}
public void setAttendees(Set attendees) {
this.attendees = attendees;
}
}

/////////////////////////////////////////////////////////////////////////
<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC
"-//Hibernate/Hibernate Mapping DTD 2.0//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-2.0.dtd">
<hibernate-mapping>
<class name="SpeakerManyToMany" table="m_speakers">
<id name="id" column="uid" type="long">
<generator class="increment"/>
</id>
<property name="firstName" type="string" length="20"/>
<property name="lastName" type="string" length="20"/>
<set name="events" table="event_speakers" cascade="all">
<key column="speaker_id"/>
<many-to-many class="EventManyToMany"/>
</set>
</class>
</hibernate-mapping>

/////////////////////////////////////////////////////////////////////////
import java.util.Set;
import java.util.HashSet;
public class SpeakerManyToMany {
private Long id;
private String firstName;
private String lastName;
private Set events;
public SpeakerManyToMany() {
}
public SpeakerManyToMany(String firstName, String lastName) {
setFirstName(firstName);
setLastName(lastName);
}
public SpeakerManyToMany(String firstName, String lastName, EventManyToMany event) {
this(firstName, lastName);
addEvent(event);
}
public Long getId() {
return id;
}
public void setId(Long id) {
this.id = id;
}
public String getFirstName() {
return firstName;
}
public void setFirstName(String firstName) {
this.firstName = firstName;
}
public String getLastName() {
return lastName;
}
public void setLastName(String lastName) {
this.lastName = lastName;
}
public Set getEvents() {
return this.events;
}
public void setEvents(Set events) {
this.events = events;
}
private void addEvent(EventManyToMany event) {
if (events == null) {
events = new HashSet();
}
events.add(event);
}
}

/////////////////////////////////////////////////////////////////////////

</source>

← Предыдущая	Версия 06:51, 1 июня 2010
(нет различий)

Java/Hibernate/Relation Many to Many - История изменений

Admin: 1 версия

в 18:01, 31 мая 2010