hibernate分页查询的实现

hibernate分页查询的实现
在mysql中新建数据好USER表，字段有3个，分别是id、username、password，贴上脚本仅供参考

create table `ding`.`user`(

`id` intdefault
'' not
null,

`username` varchar(30),

`password` varchar(30),

primary key (`id`)

);

切换到数据库透视图，新建一个mysql连接（这里就不再多说了）。

新建一个web工程，然后右键选择myeclipse，选择add hibernate........ ，把hibernate的jar加入到工程中，选择的时候注意jar包要放在lib中，可以检查下，其中有一下会选择刚新建的mysql连接，加完以后就会看到SRC下多了一个hibernate.cfg.xml文件，内容包含了配置的连接信息，如下：

<?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/ding

</property>

<property name="dialect">

org.hibernate.dialect.MySQLDialect

</property>

<property name="myeclipse.connection.profile">mysql</property>

<property name="connection.password">ding</property>

<property name="connection.driver_class">

com.mysql.jdbc.Driver

</property>

</session-factory>

</hibernate-configuration>

切换到数据库透视图，启动那个连接找到建的USER表，右键选择Hibernate Reverse Engineering...，在弹出的框里面点击 Java src folder 一行最右侧的 Browser.. 按钮来选择源码目录，这里我选择自己工程src 目录，并把下面的 Java package 右侧的输入框中输入自己想要的包名，我这里是test，接着选中下面的复选框，我选前面两个:

[x] Hibernate mapping file (*.hbm.xml) for each database table

[x] Java Data Object (POJO <> DB Table)

第2项下面的复选create abstract class我这里不选，点击next，再在ID generator选择increment（自增长），点完成。

返回j2ee透视图，会看到在test包下生成了User.java和User.hbm.xml文件，如下：

public class Userimplements java.io.Serializable {

private Integer id;

private String username;

private String password;

public Integer getId() {

returnthis.id;

}

public
void setId(Integer id) {

this.id= id;

}

public String getUsername() {

returnthis.username;

}

public
void setUsername(String username) {

this.username= username;

}

public String getPassword() {

returnthis.password;

}

public
void setPassword(String password) {

this.password= password;

}

}

<?xml version="1.0"
encoding="utf-8"?>

<!DOCTYPE hibernate-mapping PUBLIC"-//Hibernate/Hibernate
Mapping DTD 3.0//EN"

"http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">

<!--

Mapping file autogenerated by MyEclipse Persistence Tools

-->

<hibernate-mapping>

<class name="test.User"
table="user">

<id name="id"
type="java.lang.Integer">

<column name="id"/>

<generatorclass="increment"/>

</id>

<property name="username"
type="java.lang.String">

<column name="username"
length="30"/>

</property>

<property name="password"
type="java.lang.String">

<column name="password"
length="30"/>

</property>

</class>

</hibernate-mapping>

同时在原先的hibernate.cfg.xml中加入了 <mapping resource="test/User.hbm.xml" />，最终的hibernate.cfg.xml文件如下：

<?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/ding

</property>

<property name="dialect">

org.hibernate.dialect.MySQLDialect

</property>

<property name="myeclipse.connection.profile">mysql</property>

<property name="connection.password">ding</property>

<property name="connection.driver_class">

com.mysql.jdbc.Driver

</property>

<mapping resource="test/User.hbm.xml"/>

</session-factory>

</hibernate-configuration>

写个Test测试类

public class Test {

/**

* @Description 方法实现功能描述

* @param args

* void

* @throws 抛出异常说明

*/

public
static void main(String[] args) {

SessionFactory sf =new Configuration().configure().buildSessionFactory();

Session session = sf.openSession();

String hql ="from User";

int curpage=
1;//当前页

int pagesize=
2;//每页显示数

//以上两项有一项为0则查出所有记录

List list = findOnePage(session, hql, curpage, pagesize);

for(Iterator i= list.iterator();i.hasNext();){

User user = (User) i.next();

System.out.println("username==="+user.getUsername());

}

}

public
static List findOnePage(Session session,String strHQL,int offset,
int pagesize){

List lst =null;

try {

Query query = session.createQuery(strHQL);

if (offset!=
0&& pagesize!=
0) {

query.setFirstResult((offset -1)
* pagesize);

query.setMaxResults(pagesize);

}

lst = query.list();

} catch (Exception ex) {

ex.printStackTrace();

}

return lst;

}

}