Hibernate逍遥游记-第3章对象-关系映射基础-access="field"、dynamic-insert、dynamic-update、formula、update=false

1.

package mypack;

import java.util.*;

public class Monkey{

  private Long id;
  private String firstname;
  private String lastname;
  private char gender;
  private int age;
  private int avgAge;
  private String description;

  public Monkey() {}

  public Monkey(String firstname,String lastname,char gender,int age,String description){
    this.firstname=firstname;
    this.lastname=lastname;
    this.gender=gender;
    this.age=age;
    this.description=description;
  }

  public Long getId() {
    return this.id;
  }

  private 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 String getName(){
    return firstname+ " "+lastname;
  }

  public void setName(String name){
    StringTokenizer t=new StringTokenizer(name);
    firstname=t.nextToken();
    lastname=t.nextToken();
  }

  public int getAge(){
    return this.age;
  }

  public void setAge( int age ){
    this.age = age;
  }

  public int getAvgAge(){
    return this.avgAge;
  }

  private void setAvgAge( int avgAge){
    this.avgAge = avgAge;
  }

  public char getGender(){
    return this.gender;
  }
  
  public void setGender(char gender){
    if(gender!='F' && gender!='M'){
      throw new IllegalArgumentException("Invalid Gender");
    }
    this.gender =gender ;
  }

  public String getDescription(){
    return this.description;
  }

  public void setDescription(String description){
    this.description=description;
  }
}

 

2.

<?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="mypack.Monkey" table="MONKEYS" dynamic-insert="true" dynamic-update="true" >
    <id name="id">
      <generator class="increment"/>
    </id>

    <property name="name" column="NAME" /> 
    <property name="gender" column="GENDER" access="field" />
    <property name="age" column="AGE" />

    <property name="avgAge" 
       formula="(select avg(m.AGE) from MONKEYS m)" />

   <property name="description"  type="text" column="`MONKEY  DESCRIPTION`"/>
  
 </class>
</hibernate-mapping>

 

3.

package mypack;

import org.hibernate.*;
import org.hibernate.cfg.Configuration;
import java.util.*;

public class BusinessService{
  public static SessionFactory sessionFactory;
  static{
     try{
       Configuration config = new Configuration()
                              .configure(); //加载hibernate.cfg.xml文件中配置的信息
      sessionFactory = config.buildSessionFactory();
    }catch(RuntimeException e){e.printStackTrace();throw e;}
  }

  public Monkey loadMonkey(long monkey_id){
    Session session = sessionFactory.openSession();
    Transaction tx = null;
    try {
      tx = session.beginTransaction();
      Monkey monkey=(Monkey)session.get(Monkey.class,new Long(monkey_id));
      tx.commit();
      return monkey;
    }catch (RuntimeException e) {
      if (tx != null) {
         tx.rollback();
      }
      throw e;
    } finally {
       session.close();
    }
  }

  public void saveMonkey(Monkey monkey){
    Session session = sessionFactory.openSession();
    Transaction tx = null;
    try {
      tx = session.beginTransaction();
      session.save(monkey);
      tx.commit();

    }catch (RuntimeException e) {
      if (tx != null) {
         tx.rollback();
      }
      throw e;
    } finally {
       session.close();
    }
  }

  public void loadAndUpdateMonkey(long monkeyId) {
    Session session = sessionFactory.openSession();
    Transaction tx = null;
    try {
      tx = session.beginTransaction();
      Monkey monkey=(Monkey)session.get(Monkey.class,new Long(monkeyId));
      monkey.setDescription("勇敢无畏!");
      tx.commit();

    }catch (RuntimeException e) {
      if (tx != null) {
        tx.rollback();
      }
      throw e;
    } finally {
      session.close();
    }
  }

  public void updateMonkey(Monkey monkey){
    Session session = sessionFactory.openSession();
    Transaction tx = null;
    try {
      tx = session.beginTransaction();
      session.update(monkey);
      tx.commit();

    }catch (RuntimeException e) {
      if (tx != null) {
         tx.rollback();
      }
      throw e;
    } finally {
       session.close();
    }
  }


  public void printMonkey(Monkey monkey){
    System.out.println("name:"+monkey.getName());
    System.out.println("gender:"+monkey.getGender());
    System.out.println("description:"+monkey.getDescription());
    System.out.println("age:"+monkey.getAge());
    System.out.println("avgAge:"+monkey.getAvgAge());
  }

   public void test(){
      Monkey monkey=new Monkey("悟空","孙",'M',500,"神通广大!");
      saveMonkey(monkey);

      monkey=loadMonkey(1);
      printMonkey(monkey);

      monkey.setDescription("齐天大圣!");
      updateMonkey(monkey);
      printMonkey(monkey);

      loadAndUpdateMonkey(1);
      printMonkey(monkey);
   }

  public static void main(String args[]) {
    new BusinessService().test();
    sessionFactory.close();
  }
}

 

4.

<?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="dialect">
            org.hibernate.dialect.MySQLDialect
        </property>
        <property name="connection.driver_class">
            com.mysql.jdbc.Driver
        </property>
        <property name="connection.url">
            jdbc:mysql://localhost:3306/sampledb
        </property>
        <property name="connection.username">
            root
        </property>
        <property name="connection.password">
            1234
        </property>
        <property name="show_sql">true</property>
        <mapping resource="mypack/Monkey.hbm.xml" />
    </session-factory>
</hibernate-configuration>

 

5.

drop database if exists SAMPLEDB;
create database SAMPLEDB;
use SAMPLEDB;

create table MONKEYS (
   ID bigint not null,
   NAME varchar(15),
   GENDER char(1),
   AGE int,
   `MONKEY  DESCRIPTION` text,
   primary key (id)
);