<hibernate-mapping>
    <class name="stu.one2many.pojo.Tclass" table="tclass">
        <id name="cid" type="java.lang.Long">
            <column name="cid"/>
            <generator class="native"/>
        </id>
        <property name="cname" type="java.lang.String">
            <column name="cname" length="24" not-null="true"/>
        </property>
        <!-- set元素属性说明：
           name="students" 设置表示多个学生的变量名；
           inverse="true" 关系控制反转,不掌握主控权,表示Tclass不控制与Student关联关系，而是将这种关联控制的权利转给Student。
           cascade="all" 表示级联操作，操作班级的时候，对班级关联的学生也做同样的操作。
           lazy="true" 查询班级的时候，延迟查询班级下的学生。
        -->
        <set name="students" inverse="true" cascade="all" lazy="true">
            <key>
                <!--
                    name="fk_cid" 指定关联的外键列；
                    not-null="true" 说明这个外间列不能为空，多余的。
                -->
                <column name="fk_cid" not-null="true"/>
            </key>
            <!-- 指定所关联的类 -->
            <one-to-many class="stu.one2many.pojo.Student"/>
        </set>
    </class>
</hibernate-mapping>

<hibernate-mapping>
    <class name="stu.one2many.pojo.Student" table="student">
        <id name="sid" type="java.lang.Long">
            <column name="sid" />
            <generator class="native" />
        </id>
        <!-- 表示多个Student关联一个Tclass -->
        <!--  
            name="tclass" 关联的成员变量名;
            class="stu.one2many.pojo.Tclass" 表示所关联的类;
            fetch="select" 查询策略,有两个选项select和join,
          select表示通过外联接来进行查询,查询速度稍慢,但消耗资源少;
          join表示通过内连接来查询,速度快,但消耗资源多.
         -->
        <many-to-one name="tclass"  
            class="stu.one2many.pojo.Tclass"  
            fetch="select">
            <!-- 指定关联的外键列 -->
            <column name="fk_cid" not-null="true" />
        </many-to-one>
        <property name="sname" type="java.lang.String">
            <column name="sname" length="24" not-null="true" />
        </property>
    </class>
</hibernate-mapping>

public class Test {

    /**
     * @param args
     */
    public static void main(String[] args) {
        testSave();
//        testDeleteTclass();

    }

    public static void testSave() {
        Tclass c = new Tclass();
        c.setCname("某班级");
        Student s1 = new Student();
        Student s2 = new Student();
        s1.setSname("张三");
        s1.setTclass(c);
        s2.setSname("李四");
        s2.setTclass(c);
        c.getStudents().add(s1);
        c.getStudents().add(s2);

        Session session = HibernateSessionFactory.getSession();
        Transaction tx = session.beginTransaction();
        session.save(c);
        tx.commit();
        session.close();
    }

    public static void testUpdateClass() {
        System.out.println("----------------正在调用testUpdateClass()----------------");
        Session session = HibernateSessionFactory.getSession();
        Tclass c = (Tclass) session.load(Tclass.class, Long.valueOf(1L));
        System.out.println(c);
        c.setCname("班级更名");
        session.beginTransaction().commit();
    }

    public static void testUpdateStudent() {
        System.out.println("----------------正在调用testUpdateStudent()----------------");
        Session session = HibernateSessionFactory.getSession();
        Tclass c = (Tclass) session.load(Tclass.class, Long.valueOf(3L));
        Student s = (Student) session.load(Student.class, Long.valueOf(2L));
        s.setSname("学生改名换姓-王八");
        s.setTclass(c);
        System.out.println(c);
        System.out.println(s);
        session.beginTransaction().commit();
        System.out.println(s);
        System.out.println(s.getTclass());
    }

    public static void testDeleteStudent() {
        System.out.println("----------------正在调用testDelete()----------------");
        Session session = HibernateSessionFactory.getSession();
        Student s = (Student) session.load(Student.class, Long.valueOf(5L));
        System.out.println(s);
        System.out.println(s.getTclass());
        session.delete(s);
        session.beginTransaction().commit();
    }

    public static void testDeleteTclass() {
        System.out.println("----------------正在调用testDelete()----------------");
        Session session = HibernateSessionFactory.getSession();
        Tclass c = (Tclass) session.load(Tclass.class, Long.valueOf(3L));
        System.out.println(c);
        session.delete(c);
        session.beginTransaction().commit();
    }

    public static void testQueryClass() {
        System.out.println("----------------正在调用testQueryClass()----------------");
        Session session = HibernateSessionFactory.getSession();
        Tclass c = (Tclass) session.load(Tclass.class, new Long("1"));
        System.out.println(c);
        System.out.println(c.getStudents());

    }

    public static void testQueryStudent() {
        System.out.println("----------------正在调用testQueryStudent()----------------");
        Session session = HibernateSessionFactory.getSession();
        Student s = (Student) session.load(Student.class, new Long("1"));
        System.out.println(s);
        System.out.println(s.getTclass());
    }
}

public class Foo implements java.io.Serializable {

    // Fields

    private Long pid;

    private Integer version;

    private String name;

    // Constructors
    // Property accessors
    .......

    public String toString() {
        return "Foo{" +
                "pid=" + pid +
                ", version=" + version +
                ", name='" + name + '\'' +
                '}';
    }
}

<hibernate-mapping>
    <class name="stu.one2many.pojo.Foo" table="foo"  
           optimistic-lock="version">
        <id name="pid" type="java.lang.Long">
            <column name="pid" />
            <generator class="native" />
        </id>
        <!-- 版本控制字段必须在id后配置 -->
        <version name="version" type="java.lang.Integer">
            <column name="version" />
        </version>
        <property name="name" type="java.lang.String">
            <column name="name" length="24" not-null="true" />
        </property>
    </class>
</hibernate-mapping>

public class TestFoo {

    /**
  * @param args
  */
    public static void main(String[] args) {
  testSave();
  
    }
    public static void testSave(){
  Foo foo1 = new Foo("foo1");
  
  Session session = HibernateSessionFactory.getSession();
  session.save(foo1);
  session.beginTransaction().commit();
        session.close();
    }
}

public class Bar implements java.io.Serializable, Comparable {

    // Fields    

    private Long id;
    private Date timestamp;
    private String name;

    // Constructors
    // Property accessors
    .......

    public String toString() {
        return "Bar{" +
                "id=" + id +
                ", timestamp=" + timestamp +
                ", name='" + name + '\'' +
                '}';
    }

    /**
     * 排序接口方法实现，为了能对查询结果按照id的大小进行排序
     * @param o 排序对象
     * @return 比较值
     */
    public int compareTo(Object o) {
        Bar bar = (Bar) o;
        Long res = this.id - bar.getId();
        return res.intValue();
    }
}

<hibernate-mapping>
    <class name="stu.one2many.pojo.Bar" table="bar" optimistic-lock="version">
        <id name="id" type="java.lang.Long">
            <column name="id" />
            <generator class="native" />
        </id>
        <version name="timestamp" type="java.util.Date">
            <column name="timestamp" length="0" not-null="true" />
        </version>
        <property name="name" type="java.lang.String">
            <column name="name" length="24" not-null="true" />
        </property>
    </class>
</hibernate-mapping>

public class TestBar {
    public static void main(String args[]) {
        testUpdateBar();
        testQueryBar();
    }

    public static void testSaveBar() {
        Bar bar = new Bar("bar");
        Session session = HibernateSessionFactory.getSession();
        session.save(bar);
        session.beginTransaction().commit();
        session.close();
    }

    public static void testQueryBar() {
        Session session = HibernateSessionFactory.getSession();
        String hql = "from Bar";
        Query query = session.createQuery(hql);
        List<Bar> barList = query.list();
        Collections.sort(barList);
        for (Bar bar : barList) {
            System.out.println(bar.getId() + ":\t" + bar.getTimestamp().getTime());
        }
        session.close();
    }

    public static void testUpdateBar() {
        Session session = HibernateSessionFactory.getSession();
        String hql = "from Bar";
        Query query = session.createQuery(hql);
        List<Bar> barList = query.list();
        for (Bar bar : barList) {
            bar.setName("newBar");
        }
        session.beginTransaction().commit();
        session.close();
    }
}

public class TestStack {
    public static void main(String args[]){
        test();
    }
    public static void  test(){
        Stack stack = new Stack();
        String s1= "1";
        String s2="2";
        String s3= "3";
        String s4= "4";
        stack.push(s1);
        stack.push(s2);
        stack.push(s3);
        stack.push(s4);

        for(;!stack.isEmpty();){
            System.out.println(stack.pop());
        }

        //for语句先判断是否符合条件,然后确定是否执行循环
        for(int i=0;i>10;i--){
            System.out.println(">>> "+i);
        }
    }
}

import org.hibernate.HibernateException;
import org.hibernate.Session;
import org.hibernate.cfg.Configuration;

/**
* Configures and provides access to Hibernate sessions, tied to the
* current thread of execution.  Follows the Thread Local Session
* pattern, see {@link http://hibernate.org/42.html }.
*/
public class HibernateSessionFactory {

    /**  
     * Location of hibernate.cfg.xml file.
     * Location should be on the classpath as Hibernate uses  
     * #resourceAsStream style lookup for its configuration file.  
     * The default classpath location of the hibernate config file is  
     * in the default package. Use #setConfigFile() to update  
     * the location of the configuration file for the current session.    
     */
    private static String CONFIG_FILE_LOCATION = "/hibernate.cfg.xml";
    private static final ThreadLocal<Session> threadLocal = new ThreadLocal<Session>();
    private  static Configuration configuration = new Configuration();
    private static org.hibernate.SessionFactory sessionFactory;
    private static String configFile = CONFIG_FILE_LOCATION;

    static {
        try {
      configuration.configure(configFile);
      sessionFactory = configuration.buildSessionFactory();
  } catch (Exception e) {
      System.err
        .println("%%%% Error Creating SessionFactory %%%%");
      e.printStackTrace();
  }
    }
    private HibernateSessionFactory() {
    }
  
    /**
     * Returns the ThreadLocal Session instance.  Lazy initialize
     * the <code>SessionFactory</code> if needed.
     *
     *  @return Session
     *  @throws HibernateException
     */
    public static Session getSession() throws HibernateException {
        Session session = (Session) threadLocal.get();

  if (session == null || !session.isOpen()) {
      if (sessionFactory == null) {
    rebuildSessionFactory();
      }
      session = (sessionFactory != null) ? sessionFactory.openSession()
        : null;
      threadLocal.set(session);
  }

        return session;
    }

    /**
     *  Rebuild hibernate session factory
     *
     */
    public static void rebuildSessionFactory() {
  try {
      configuration.configure(configFile);
      sessionFactory = configuration.buildSessionFactory();
  } catch (Exception e) {
      System.err
        .println("%%%% Error Creating SessionFactory %%%%");
      e.printStackTrace();
  }
    }

    /**
     *  Close the single hibernate session instance.
     *
     *  @throws HibernateException
     */
    public static void closeSession() throws HibernateException {
        Session session = (Session) threadLocal.get();
        threadLocal.set(null);

        if (session != null) {
            session.close();
        }
    }

    /**
     *  return session factory
     *
     */
    public static org.hibernate.SessionFactory getSessionFactory() {
  return sessionFactory;
    }

    /**
     *  return session factory
     *
     *    session factory will be rebuilded in the next call
     */
    public static void setConfigFile(String configFile) {
  HibernateSessionFactory.configFile = configFile;
  sessionFactory = null;
    }

    /**
     *  return hibernate configuration
     *
     */
    public static Configuration getConfiguration() {
  return configuration;
    }

}

<?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">

<!-- Generated by MyEclipse Hibernate Tools.                   -->
<hibernate-configuration>

    <session-factory>
  <property name="connection.username">root</property>
  <property name="connection.url">
      jdbc:mysql://localhost:3306/testdb
  </property>
  <property name="dialect">
      org.hibernate.dialect.MySQLDialect
  </property>
  <property name="myeclipse.connection.profile">
      com.mysql.jdbc.Driver
  </property>
  <property name="connection.password">leizhimin</property>
  <property name="connection.driver_class">
      com.mysql.jdbc.Driver
  </property>
  <property name="show_sql">true</property>
  <!--<property name="format_sql">true</property>-->
        <property name="hbm2ddl.auto">create</property>


        <mapping resource="stu/one2many/pojo/Tclass.hbm.xml" />
  <mapping resource="stu/one2many/pojo/Student.hbm.xml" />
  <mapping resource="stu/one2many/pojo/Foo.hbm.xml"></mapping>
  <mapping resource="stu/one2many/pojo/Bar.hbm.xml" />

    </session-factory>

</hibernate-configuration>

/*
SQLyog Enterprise - MySQL GUI v6.5
MySQL - 5.0.45-community-nt : Database - testdb
*********************************************************************
*/


/*!40101 SET NAMES utf8 */;

/*!40101 SET SQL_MODE=''*/;

/*!40014 SET @OLD_FOREIGN_KEY_CHECKS=@@FOREIGN_KEY_CHECKS, FOREIGN_KEY_CHECKS=0 */;
/*!40101 SET @OLD_SQL_MODE=@@SQL_MODE, SQL_MODE='NO_AUTO_VALUE_ON_ZERO' */;

create database if not exists testdb;

USE testdb;

/*Table structure for table bar */

DROP TABLE IF EXISTS bar;

CREATE TABLE bar (
  id bigint(20) NOT NULL auto_increment,
  timestamp datetime NOT NULL,
  name varchar(24) NOT NULL,
  PRIMARY KEY  (id)
) ENGINE=InnoDB DEFAULT CHARSET=gbk;

/*Table structure for table foo */

DROP TABLE IF EXISTS foo;

CREATE TABLE foo (
  pid bigint(20) NOT NULL auto_increment,
  version int(11) NOT NULL,
  name varchar(24) NOT NULL,
  PRIMARY KEY  (pid)
) ENGINE=InnoDB DEFAULT CHARSET=gbk;

/*Table structure for table student */

DROP TABLE IF EXISTS student;

CREATE TABLE student (
  sid bigint(20) NOT NULL auto_increment,
  fk_cid bigint(20) NOT NULL,
  sname varchar(24) NOT NULL,
  PRIMARY KEY  (sid),
  KEY FK8FFE823B3AA29689 (fk_cid),
  CONSTRAINT FK8FFE823B3AA29689 FOREIGN KEY (fk_cid) REFERENCES tclass (cid)
) ENGINE=InnoDB AUTO_INCREMENT=3 DEFAULT CHARSET=gbk;

/*Table structure for table tclass */

DROP TABLE IF EXISTS tclass;

CREATE TABLE tclass (
  cid bigint(20) NOT NULL auto_increment,
  cname varchar(24) NOT NULL,
  PRIMARY KEY  (cid)
) ENGINE=InnoDB AUTO_INCREMENT=2 DEFAULT CHARSET=gbk;

/*!40101 SET SQL_MODE=@OLD_SQL_MODE */;
/*!40014 SET FOREIGN_KEY_CHECKS=@OLD_FOREIGN_KEY_CHECKS */;