Java/Hibernate/Hibernate Data Type
Содержание
Date Calendar Type Demo
<source lang="java">
///////////////////////////////////////////////////////////////////////// <?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="BasicAccount" table="account">
<id name="id" type="string" unsaved-value="null">
<generator class="uuid.hex"/>
</id>
<property name="name"/>
<property name="accountnumber"/>
<property name="setupdate">
<column name="setup" sql-type="Date"/>
</property>
<property name="balance" type="double"/>
</class>
</hibernate-mapping> ///////////////////////////////////////////////////////////////////////// import java.util.*; public class BasicAccount {
private String id;
private String name;
private String accountnumber;
private Date setupdate;
private double balance;
public BasicAccount() {
}
public void setId(String s) {
id = s;
}
public String getId() {
return id;
}
public void setName(String s) {
name = s;
}
public String getName() {
return name;
}
public void setAccountnumber(String s) {
accountnumber = s;
}
public String getAccountnumber() {
return accountnumber;
}
public void setSetupdate(Date d) {
setupdate = d;
}
public Date getSetupdate() {
return setupdate;
}
public void setBalance(double d) {
balance = d;
}
public double getBalance() {
return balance;
}
}
/////////////////////////////////////////////////////////////////////////
<?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="BasicAccount.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);
System.out.print(value.toString().trim()+" ");
}
}
}
} /////////////////////////////////////////////////////////////////////////
import java.io.Serializable; import java.util.*; import java.sql.*; 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 account (id varchar not null,name varchar,accountnumber varchar,setup Date,balance double);");
Session session = HibernateUtil.currentSession();
BasicAccount account = new BasicAccount();
account.setName("Joe");
account.setAccountnumber("39084");
account.setSetupdate(new java.util.Date());
account.setBalance(4054.00);
session.save(account);
session.flush();
BasicAccount account2 = (BasicAccount)session.load
(BasicAccount.class, account.getId());
System.out.println(account.getId() + " : " + account.getSetupdate());
System.out.println(account2.getId() +
" : " + account2.getSetupdate());
session.close();
session.close();
HibernateUtil.checkData("select * from account");
}
}
/////////////////////////////////////////////////////////////////////////
</source>
Float Data Type
<source lang="java">
///////////////////////////////////////////////////////////////////////// import java.io.Serializable; import java.util.*; import java.sql.*; 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 books(id int, title VARCHAR, author VARCHAR,isbn VARCHAR not null, pagecount int, copyright int, cost numeric(12,2));");
Session session = HibernateUtil.currentSession();
Book book = new Book();
book.setTitle("Title");
book.setIsbn("000000000000000");
book.setAuthor("name");
book.setCopyright(9);
book.setPages(330);
book.setCost(29.99f);
session.save(book);
session.flush();
session.close();
HibernateUtil.checkData("select * from books");
}
}
/////////////////////////////////////////////////////////////////////////
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);
System.out.print(value.toString().trim()+" ");
}
}
}
} ///////////////////////////////////////////////////////////////////////// <?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="Book.hbm.xml"/>
</session-factory>
</hibernate-configuration>
/////////////////////////////////////////////////////////////////////////
public class Book{
private int id;
private String title;
private String author;
private String isbn;
private int pages;
private int copyright;
private float cost;
public Book() {
}
public void setId(int i) {
id = i;
}
public int getId() {
return id;
}
public void setTitle(String s) {
title = s;
}
public String getTitle() {
return title;
}
public void setAuthor(String s) {
author = s;
}
public String getAuthor() {
return author;
}
public void setIsbn(String s) {
isbn = s;
}
public String getIsbn() {
return isbn;
}
public void setPages(int i) {
pages = i;
}
public int getPages() {
return pages;
}
public void setCopyright(int i) {
copyright = i;
}
public int getCopyright() {
return copyright;
}
public void setCost(float f) {
cost = f;
}
public float 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="Book" table="books">
<id name="id" type="int" unsaved-value="0">
<generator class="increment"/>
</id>
<property name="title"/>
<property name="author"/>
<property name="isbn" not-null="true"/>
<property name="pages" type="integer" column="pagecount" />
<property name="copyright"/>
<property name="cost">
<column name="cost" sql-type="NUMERIC(12,2)"/>
</property>
</class> </hibernate-mapping>
/////////////////////////////////////////////////////////////////////////
</source>
Java Type VS Hibernate Type
<source lang="java">
/* Chapter 4 - Database Connecting and Schema Generation Professional Hibernate by Eric Pugh and Joseph D. Gradecki Wrox Press 2004
- /
Java Class Attribute Type Hibernate Type Possible SQL Type-Vendor Specific Integer, int, long short integer, long, short Appropriate SQL type char character char java.math.BigDecimal big_decimal NUMERIC, NUMBER float, double float, double float, double java.lang.Boolean, boolean boolean, yes_no, boolean, int
true_false
java.lang.string string varchar, varchar2 Very long strings text CLOB, TEXT java.util.Date date, time, timestamp DATE, TIME, TIMESTAMP java.util.Calendar calendar, calendar_date TIMESTAMP, DATE java.util.Locale locale varchar,varchar2 java.util.TimeZone timezone varchar, varchar2 java.util Currency Currency varchar, varchar2 java.sql.Clob clob CLOB java.sql.Blob blob BLOB Java object serializable binary field byte array binary binary field java.lang.Class class varchar, varchar2
</source>
Mapping Blob Binary Data Just Mapping (have bugs)
Save Date Type
<source lang="java">
///////////////////////////////////////////////////////////////////////// import java.util.Date; import org.hibernate.Session; import org.hibernate.Transaction; public class SimpleSaveTest {
public static void main(String[] args) {
HibernateUtil.setup("create table EVENTS ( EVENT_ID int, EVENT_DATE date, title VARCHAR);");
// hibernate code start
Session session = HibernateUtil.currentSession();
Transaction tx = session.beginTransaction();
Event theEvent = new Event();
theEvent.setTitle("My Event");
theEvent.setDate(new Date());
session.save(theEvent);
tx.rumit();
HibernateUtil.closeSession();
HibernateUtil.sessionFactory.close();
// hibernate code end
HibernateUtil.checkData("select * from events;");
}
}
///////////////////////////////////////////////////////////////////////// <?xml version="1.0"?> <!DOCTYPE hibernate-mapping PUBLIC
"-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">
<hibernate-mapping>
<class name="Event" table="EVENTS">
<id name="id" column="EVENT_ID">
<generator class="increment"/>
</id>
<property name="date" type="timestamp" column="EVENT_DATE"/>
<property name="title"/>
</class>
<class name="EventWithAttendee" table="eventwithattendee">
<id name="id" column="uid" type="long" unsaved-value="null">
<generator class="native"/>
</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="Location"/>
<set name="attendees" cascade="all">
<key column="event_id"/>
<one-to-many class="EventAttendee"/>
</set>
</class>
<class name="EventAttendee" table="attendees">
<id name="id" column="uid" type="long">
<generator class="native"/>
</id>
<property name="firstName" type="string" length="20"/>
<property name="lastName" type="string" length="20"/>
</class>
<class name="Location" table="locations">
<id name="id" column="uid" type="long">
<generator class="native"/>
</id>
<property name="name" type="string"/>
<property name="address" type="string"/>
</class>
</hibernate-mapping>
/////////////////////////////////////////////////////////////////////////
import java.util.Date; public class Event {
private Long id;
private String title;
private Date date;
Event() {
}
public Long getId() {
return id;
}
private void setId(Long id) {
this.id = id;
}
public Date getDate() {
return date;
}
public void setDate(Date date) {
this.date = date;
}
public String getTitle() {
return title;
}
public void setTitle(String title) {
this.title = title;
}
public String toString() {
return "ID:" + id + "\nTitle:" + title + "\nDate:" + date;
}
}
</source>
