Hibernate分页查询的实现

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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;
    }

}

测试下就可以看到效果了
   int curpage = 1;//当前页
   int pagesize = 2;//每页显示数
可以改这两个参数试试
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