Hibernate(四)

==================================投影（查询）=============================
投影查询：查询一个持久化类的一个或多个属性值
    1.将每条查询结果封装成Object对象
    2.将每条查询结果封装成Object数组
    3.将每条查询结果通过构造函数封装成对象

范例1：java.lang.ClassCastException: [Ljava.lang.Object; cannot be cast to com.Elastic.HibernateDemo3.ivy.entity.Dept
      [L：数组

 package com.Elastic.HibernateDemo3.ivy.test;

 import java.util.HashMap;

 import java.util.List;

 import java.util.Map;

 import org.hibernate.Query;

 import org.hibernate.SQLQuery;

 import org.hibernate.Session;

 import com.Elastic.HibernateDemo3.ivy.entity.Emp;

 import com.Elastic.HibernateDemo3.ivy.util.HibernateUtil;

 public class Test {

     public static void main(String[] args) {

         Session session = HibernateUtil.getSession();

         String hql = "select deptName,location from Dept";

         Query query = session.createQuery(hql);

         //2.将每条查询结果封装成Object数组

         List<Dept> depts = query.list();

         for (Dept dept : depts) {

             System.out.println(dept.getDeptName());

         }

     }

 }

范例2： Exception in thread "main" org.hibernate.hql.ast.QuerySyntaxException: expecting OPEN, found '[' near line 1, column 16 [select new Dept[deptName,location] from com.Elastic.HibernateDemo3.ivy.entity.Dept]

 package com.Elastic.HibernateDemo3.ivy.test;

 import java.util.HashMap;

 import java.util.List;

 import java.util.Map;

 import org.hibernate.Query;

 import org.hibernate.SQLQuery;

 import org.hibernate.Session;

 import com.Elastic.HibernateDemo3.ivy.entity.Emp;

 import com.Elastic.HibernateDemo3.ivy.util.HibernateUtil;

 public class Test {

     public static void main(String[] args) {

         Session session = HibernateUtil.getSession();

         //3.将每条查询结果通过构造函数封装成对象

         String hql = "select new Dept[deptName,location] from Dept";

         Query query = session.createQuery(hql);

         List<Dept> depts = query.list();

         for (Dept dept : depts) {

             System.out.println(dept.getDeptName());

         }

     }

 }

范例3：Exception in thread "main" org.hibernate.hql.ast.QuerySyntaxException: expecting OPEN, found '[' near line 1, column 16 [select new Dept[deptName,location] from com.Elastic.HibernateDemo3.ivy.entity.Dept]

 package com.Elastic.HibernateDemo3.ivy.test;

 import java.util.HashMap;

 import java.util.List;

 import java.util.Map;

 import org.hibernate.Query;

 import org.hibernate.SQLQuery;

 import org.hibernate.Session;

 import com.Elastic.HibernateDemo3.ivy.entity.Emp;

 import com.Elastic.HibernateDemo3.ivy.util.HibernateUtil;

 public class Test {

     public static void main(String[] args) {

         Session session = HibernateUtil.getSession();

         String hql = "select new Dept[deptName,location] from Dept";

         Query query = session.createQuery(hql);

         //2.将每条查询结果封装成Object数组

         <Object> objs = query.list();

         for (Object object : objs) {

             System.out.println(object);

         }

     }

 }

范例4：Exception in thread "main" org.hibernate.hql.ast.QuerySyntaxException: expecting OPEN, found '[' near line 1, column 16 [select new Dept[deptName,location] from com.Elastic.HibernateDemo3.ivy.entity.Dept]

 package com.Elastic.HibernateDemo3.ivy.test;

 import java.util.HashMap;

 import java.util.List;

 import java.util.Map;

 import org.hibernate.Query;

 import org.hibernate.SQLQuery;

 import org.hibernate.Session;

 import com.Elastic.HibernateDemo3.ivy.entity.Emp;

 import com.Elastic.HibernateDemo3.ivy.util.HibernateUtil;

 public class Test {

     public static void main(String[] args) {

         Session session = HibernateUtil.getSession();

         //将每条查询结果封装成Object数组与将每条查询结果通过构造函数封装成对象只能选其一？？？

         String hql = "select new Dept[deptName,location] from Dept";

         Query query = session.createQuery(hql);

         List<Object[]> depts = query.list();

         for (Object[] objects : depts) {

             System.out.println(objects[0].toString() + objects[1]);

         }

     }

 }

正确范例：

 import java.util.HashMap;

 import java.util.List;

 import java.util.Map;

 import org.hibernate.Query;

 import org.hibernate.SQLQuery;

 import org.hibernate.Session;

 import com.Elastic.HibernateDemo3.ivy.entity.Emp;

 import com.Elastic.HibernateDemo3.ivy.util.HibernateUtil;

 public class Test {

     public static void main(String[] args) {

         Session session = HibernateUtil.getSession();

         String hql = "select deptName,location from Dept";

         Query query = session.createQuery(hql);

         List<Object[]> depts = query.list();

         for (Object[] objects : depts) {

             System.out.println(objects[0].toString() + objects[1]);

         }

     }

 }

========================================分页查询===============================================
范例：

 package com.Elastic.HibernateDemo3.ivy.test;

 import java.util.HashMap;

 import java.util.List;

 import java.util.Map;

 import org.hibernate.Query;

 import org.hibernate.SQLQuery;

 import org.hibernate.Session;

 import com.Elastic.HibernateDemo3.ivy.entity.Dept;

 import com.Elastic.HibernateDemo3.ivy.entity.Emp;

 import com.Elastic.HibernateDemo3.ivy.util.HibernateUtil;

 public class Test {

     public static void main(String[] args) {

         Session session = HibernateUtil.getSession();

         String hql = "from Dept";

         Query query = session.createQuery(hql);

         //当前页码

         int pageIndex = 1;

         //每页显示的条数

         int pageSize = 2;

         //设置查询的起始位置

         query.setFirstResult((pageIndex - 1) * pageSize);

         //设置每页查询的（最大）条数

         query.setMaxResults(pageSize);

         List<Dept> depts = query.list();

         for (Dept dept : depts) {

             System.out.println(dept.getDeptName());

         }

     }

 }

==================================连接查询==============================
内联：只显示互相有值的两表

左外联：左边全部显示，右边null

右外联：右边全部显示，左边null

连接类型                HQL语法
内连接                 inner join 或 join
迫切内连接           inner join fetch或 join fetch    
左外连接              left outer join或 left join    
迫切左外连接        left outer join fetch或 left join fetch
右外连接             right outer join 或right join

注意：配置文件中的fetch属性效果不大，所以一般不在配置文件中使用这个属性。而是在业务有需求时，才在业务中使用

范例：Exception in thread "main" java.lang.ClassCastException: [Ljava.lang.Object; cannot be cast to com.Elastic.HibernateDemo3.ivy.entity.Emp
      迫切连接？？？

 package com.Elastic.HibernateDemo3.ivy.test;

 import java.util.HashMap;

 import java.util.List;

 import java.util.Map;

 import org.hibernate.Query;

 import org.hibernate.SQLQuery;

 import org.hibernate.Session;

 import com.Elastic.HibernateDemo3.ivy.entity.Dept;

 import com.Elastic.HibernateDemo3.ivy.entity.Emp;

 import com.Elastic.HibernateDemo3.ivy.util.HibernateUtil;

 public class Test {

     public static void main(String[] args) {

         Session session = HibernateUtil.getSession();

         String hql = "from Emp emp inner join emp.dept";

         List<Emp> emps = session.createQuery(hql).list();

         for (Emp emp : emps) {

             System.out.println(emp.getEmpName() + emp.getDept().getDeptName());

         }

     }

 }

正确范例：

 package com.Elastic.HibernateDemo3.ivy.test;

 import java.util.HashMap;

 import java.util.List;

 import java.util.Map;

 import org.hibernate.Query;

 import org.hibernate.SQLQuery;

 import org.hibernate.Session;

 import com.Elastic.HibernateDemo3.ivy.entity.Dept;

 import com.Elastic.HibernateDemo3.ivy.entity.Emp;

 import com.Elastic.HibernateDemo3.ivy.util.HibernateUtil;

 public class Test {

     public static void main(String[] args) {

         Session session = HibernateUtil.getSession();

         String hql = "from Emp emp inner join emp.dept";

         List<Emp> emps = session.createQuery(hql).list();

         for (Emp emp : emps) {

             System.out.println(emp.getEmpName() + emp.getDept().getDeptName());

         }

     }

 }

===================================子查询================================
子查询语句：应用在HQL查询语句的where子句中

关键字                 说明
all                返回的所有记录
any              返回的任意一条记录
some            和“any”意思相同
in                与“=any”意思相同
exists           至少返回一条记录

范例：
a.查询所有员工工资都小于5000的部门
from Dept d where d.emps.size>0 and
5000>all(select e.salary from d.emps e)

b.查询至少有一位员工工资低于5000的部门
from Dept d where 5000>any(select e.salary from d.emps e)

c.查询员工工资正好是5000元的部门
from Dept d where 5000=any(select e.salary from d.emps e)
from Dept d where 5000=some(select e.salary from d.emps e)

d.查询至少有一位员工的部门
from Dept d where exists (from d.emps)
【技巧：size和exists可以表达一件事，优先考虑exists（效率高）】

====================================原生SQL查询================================
HQL 不能"统计"
SQL    提高性能，有相应数据库的优化语法

原生SQL查询：使用底层数据库的SQL特性，来生成一些特殊的查询语句

Hibernate使用★Session的createSQLQuery()方法创建SQLQuery对象★，用来执行原生SQL语句

范例1：

 package com.Elastic.HibernateDemo3.ivy.test;

 import java.util.HashMap;

 import java.util.List;

 import java.util.Map;

 import org.hibernate.Query;

 import org.hibernate.SQLQuery;

 import org.hibernate.Session;

 import com.Elastic.HibernateDemo3.ivy.entity.Dept;

 import com.Elastic.HibernateDemo3.ivy.entity.Emp;

 import com.Elastic.HibernateDemo3.ivy.util.HibernateUtil;

 public class Test {

     public static void main(String[] args) {

         Session session = HibernateUtil.getSession();

         //直接创建SQL

         String sql = "select e.*,d.* from emp e inner join dept d on e.deptId = d.deptId";

         //创建SQLQuery对象，命名查询createSQLQuery()

         SQLQuery sqlQuery = session.createSQLQuery(sql);

         sqlQuery.addEntity(Emp.class);

         List<Emp> emps = sqlQuery.list();

         for (Emp emp : emps) {

             System.out.println(emp.getEmpName() + emp.getDept().getDeptName());

         }

         //'：name' 相当 SQL语句中的 '?'。其他like等语法HQL一样用

         Query query = session

             .createSQLQuery(

             "select * from Emp where empName like :ename and Job = :job")

             .addEntity(Emp.class).setString("ename", "%张%")

             .setString("job", "工程师");

         List<Emp> list = query.list();

     }

 }

=================================命名查询=========================
命名查询语句：在映射文件中定义★字符串形式★的查询语句

HQL查询语句的命名查询，存在★***.hbm.xml★

HQL命名查询
SQL命名查询

【技巧：表单 传入两个值name和value。所以 命名时，用Map做】

范例1：

 <hibernate-mapping>

     <class name="com.xuetang9.demo.entity.Emp" table="emp">

         ......

     </class>

     <query name="findEmpByJob">

     <![CDATA[

         from Emp e where e.job = :job

     ]]>

     </query>

 </hibernate-mapping>

范例2：
1.Emp.hbm.xml

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

 <!DOCTYPE hibernate-mapping PUBLIC

     "-//Hibernate/Hibernate Mapping DTD 3.0//EN"

     "http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd">

 <hibernate-mapping>

     <!-- 实体类路径：数据库表名-->

     <class name="com.Elastic.HibernateDemo3.ivy.entity.Emp" table="emp">

         <!-- 主键UID(唯一标识) -->

         <id name="empNo" column="empNo"><!-- column单独一行，属性更全 -->

             <!-- 主键生成策略：increment，assigned，native等 -->

             <generator class="increment"></generator>

         </id>

         <!-- 属性名（★★setDeptName★★）：数据库表字段(如果是关键字，用``标志) -->

         <property name="empName" column="empName"></property>

         <!-- 这个字段进行新增和修改功能，要被Hibernate忽略。因为，与外键一样 -->

         <property name="deptId" column="deptId" insert="false" update="false"></property>

         <!-- 多对一的关系（多个员工属于一个部门） -->

         <many-to-one name="dept" class="com.Elastic.HibernateDemo3.ivy.entity.Dept" column="deptId" lazy="proxy"></many-to-one>

         <!-- fetch存在，懒加载没用。fetch不放在配置文件中 -->

     </class>

     <!-- 配置HQL命名查询 -->

     <query name="findEmpByDeptName">

         <!-- 文本 -->

         <![CDATA[

             from Emp e where e.dept.deptName = :deptname and e.empName = :ename

         ]]>

     </query>

     <!-- 配置原生的SQL语句 -->

     <sql-query name="findEmp">

         <return alias="e" class="com.Elastic.HibernateDemo3.ivy.entity.Emp"></return>

         select * from emp e inner join dept d on e.deptId = d.deptId where e.empName = :ename and d.deptName = :deptname

     </sql-query>

 </hibernate-mapping>

2.Test类

 package com.Elastic.HibernateDemo3.ivy.test;

 import java.util.HashMap;

 import java.util.List;

 import java.util.Map;

 import org.hibernate.Query;

 import org.hibernate.SQLQuery;

 import org.hibernate.Session;

 import com.Elastic.HibernateDemo3.ivy.entity.Dept;

 import com.Elastic.HibernateDemo3.ivy.entity.Emp;

 import com.Elastic.HibernateDemo3.ivy.util.HibernateUtil;

 public class Test {

     public static void main(String[] args) {

         String name = "findEmp";

         //String name = "findEmpByDeptName";

         Map<String, Object> params = new HashMap<String, Object>();

         params.put("deptname", "销售部");

         params.put("ename", "李四");

         Session session = HibernateUtil.getSession();

         Query query = session.getNamedQuery(name);

         query.setProperties(params);

         List<Emp> emps = query.list();

         for (Emp emp : emps) {

             System.out.println(emp.getEmpName() + emp.getDept().getDeptName());

         }

     }

 }

=================================综合范例==============================
1.实体类及其hbm.xml文件 -- entity包
a.Dept

 package com.Elastic.HibernateDemo3.ivy.entity;

 import java.io.Serializable;

 import java.util.Set;

 public class Dept implements Serializable {

     private static final long serialVersionUID = 2261199233032137882L;

     private Integer deptId;

     private String deptName;

     private String location;

     //多对一：一个部门有多个员工

     //set：唯一

     private Set<Emp> emps;

     public Set<Emp> getEmps() {

         return emps;

     }

     public void setEmps(Set<Emp> emps) {

         this.emps = emps;

     }

     public Integer getDeptId() {

         return deptId;

     }

     public void setDeptId(Integer deptId) {

         this.deptId = deptId;

     }

     public String getDeptName() {

         return deptName;

     }

     public void setDeptName(String deptName) {

         this.deptName = deptName;

     }

     public String getLocation() {

         return location;

     }

     public void setLocation(String location) {

         this.location = location;

     }

 }

b.Dept.hbm.xml

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

 <!DOCTYPE hibernate-mapping PUBLIC

     "-//Hibernate/Hibernate Mapping DTD 3.0//EN"

     "http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd">

 <hibernate-mapping>

     <!-- 实体类路径：数据库表名-->

     <class name="com.Elastic.HibernateDemo3.ivy.entity.Dept" table="dept">

         <!-- 主键OID(唯一标识) -->

         <id name="deptId" column="deptid"><!-- column单独一行，属性更全 -->

             <!-- 主键生成策略：increment，assigned，native等 -->

             <generator class="increment"></generator>

         </id>

         <!-- 属性名（★★setDeptName★★）：数据库表字段(如果是关键字，用``标志) -->

         <property name="deptName" column="deptname"></property>

         <property name="location" column="location"></property>

         <!-- 多个员工 -->

         <!-- <set name="emps" cascade="save-update"> --><!-- 新增部门的同时，新增员工（级联操作） -->

         <!-- <set name="emps" cascade="all" inverse="true" order-by="empNo desc"> --><!-- 删除部门同时删除员工 -->

         <set name="emps" cascade="all" inverse="true" order-by="empNo desc" lazy="extra"><!-- 删除部门同时删除员工

             表dept中deptid -->

             <key column="deptid"></key>

             <one-to-many class="com.Elastic.HibernateDemo3.ivy.entity.Emp"></one-to-many>

         </set>

     </class>

 </hibernate-mapping>

a1.Emp

 package com.Elastic.HibernateDemo3.ivy.entity;

 import java.io.Serializable;

 public class Emp implements Serializable {

     /**

      * <p>

      * <h3>作用：</h3>

      * </p>

      * @see long

      * @see serialVersionUID

      */

     private static final long serialVersionUID = -6182713107749938132L;

     private Integer empNo;

     private String empName;

     private Integer deptId;

     private Dept dept;

     public Integer getDeptId() {

         return deptId;

     }

     public void setDeptId(Integer deptId) {

         this.deptId = deptId;

     }

     public Dept getDept() {

         return dept;

     }

     public void setDept(Dept dept) {

         this.dept = dept;

     }

     public Integer getEmpNo() {

         return empNo;

     }

     public void setEmpNo(Integer empNo) {

         this.empNo = empNo;

     }

     public String getEmpName() {

         return empName;

     }

     public void setEmpName(String empName) {

         this.empName = empName;

     }

 }

b1.Emp.hbm.xml

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

 <!DOCTYPE hibernate-mapping PUBLIC

     "-//Hibernate/Hibernate Mapping DTD 3.0//EN"

     "http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd">

 <hibernate-mapping>

     <!-- 实体类路径：数据库表名-->

     <class name="com.Elastic.HibernateDemo3.ivy.entity.Emp" table="emp">

         <!-- 主键UID(唯一标识) -->

         <id name="empNo" column="empNo"><!-- column单独一行，属性更全 -->

             <!-- 主键生成策略：increment，assigned，native等 -->

             <generator class="increment"></generator>

         </id>

         <!-- 属性名（★★setDeptName★★）：数据库表字段(如果是关键字，用``标志) -->

         <property name="empName" column="empName"></property>

         <!-- 这个字段进行新增和修改功能，要被Hibernate忽略。因为，与外键一样 -->

         <property name="deptId" column="deptId" insert="false" update="false"></property>

         <!-- 多对一的关系（多个员工属于一个部门） -->

         <many-to-one name="dept" class="com.Elastic.HibernateDemo3.ivy.entity.Dept" column="deptId" lazy="proxy"></many-to-one>

         <!-- fetch存在，懒加载没用。fetch不放在配置文件中 -->

     </class>

     <!-- 配置HQL命名查询 -->

     <query name="findEmpByDeptName">

         <!-- 文本 -->

         <![CDATA[

             from Emp e where e.dept.deptName = :deptname and e.empName = :ename

         ]]>

     </query>

     <!-- 配置原生的SQL语句 -->

     <sql-query name="findEmp">

         <return alias="e" class="com.Elastic.HibernateDemo3.ivy.entity.Emp"></return>

         select * from emp e inner join dept d on e.deptId = d.deptId where e.empName = :ename and d.deptName = :deptname

     </sql-query>

 </hibernate-mapping>

2.hibernate.cfg.xml

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

 <!DOCTYPE hibernate-configuration PUBLIC

     "-//Hibernate/Hibernate Configuration DTD 3.0//EN"

     "http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd">

 <hibernate-configuration>

     <session-factory>

         <!-- 1.连接数据库 -->

         <!-- 连接数据库名 -->

         <property name="connection.url">jdbc:mysql://localhost:3306/hibernatedb</property>

         <!-- 连接数据库的用户名 -->

         <property name="connection.username">root</property>

         <!-- 连接数据库的密码 -->

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

         <!-- 数据库驱动类 -->

         <property name="connection.driver_class">com.mysql.jdbc.Driver</property>

         <!-- 2.数据库方言（不同的数据库） -->

         <property name="dialect">org.hibernate.dialect.MySQL5Dialect</property>

         <!-- 3.其他属性 -->

         <!-- 是否显示sql语句 -->

         <property name="show_sql">true</property>

         <!-- 是否显示格式化sql语句，如果要显示，★★★一定要先显示show_sql语句★★★ -->

         <property name="format_sql">true</property>

         <!-- 4.数据库对应的实体类的映射文件路径 -->

         <mapping resource="com/Elastic/HibernateDemo3/ivy/entity/Dept.hbm.xml"></mapping>

         <mapping resource="com/Elastic/HibernateDemo3/ivy/entity/Emp.hbm.xml"></mapping>

     </session-factory>

 </hibernate-configuration>

3.util包：HibernateUtil

 package com.Elastic.HibernateDemo3.ivy.util;

 import org.hibernate.Session;

 import org.hibernate.SessionFactory;

 import org.hibernate.cfg.Configuration;

 public final class HibernateUtil {

     private static Configuration cfg = null;

     private static SessionFactory sessionFactory = null;

     //本地线程

     public static ThreadLocal<Session> threadLocal = new ThreadLocal<Session>();

     static{

         cfg = new Configuration().configure();

         sessionFactory = cfg.buildSessionFactory();

     }

     public static Session getSession(){

         Session session = threadLocal.get();

         if (null == session || !session.isOpen()) {

             session = sessionFactory.openSession();

             threadLocal.set(session);

         }

         return session;

     }

 }

4.filter包
a.EncodingFilter

 package com.Elastic.HibernateDemo3.ivy.filter;

 import java.io.IOException;

 import javax.servlet.Filter;

 import javax.servlet.FilterChain;

 import javax.servlet.FilterConfig;

 import javax.servlet.ServletException;

 import javax.servlet.ServletRequest;

 import javax.servlet.ServletResponse;

 public class EncodingFilter implements Filter {

     /* (non-Javadoc)

      * @see javax.servlet.Filter#destroy()

      */

     @Override

     public void destroy() {

         // TODO Auto-generated method stub

     }

     /* (non-Javadoc)

      * @see javax.servlet.Filter#doFilter(javax.servlet.ServletRequest, javax.servlet.ServletResponse, javax.servlet.FilterChain)

      */

     @Override

     public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain)

             throws IOException, ServletException {

         request.setCharacterEncoding("utf-8");

         response.setCharacterEncoding("utf-8");

         chain.doFilter(request, response);

     }

     /* (non-Javadoc)

      * @see javax.servlet.Filter#init(javax.servlet.FilterConfig)

      */

     @Override

     public void init(FilterConfig arg0) throws ServletException {

         // TODO Auto-generated method stub

     }

 }

b.OpenSessionInViewFilter

 package com.Elastic.HibernateDemo3.ivy.filter;

 import java.io.IOException;

 import javax.servlet.Filter;

 import javax.servlet.FilterChain;

 import javax.servlet.FilterConfig;

 import javax.servlet.ServletException;

 import javax.servlet.ServletRequest;

 import javax.servlet.ServletResponse;

 import org.hibernate.HibernateException;

 import org.hibernate.Session;

 import org.hibernate.Transaction;

 import com.Elastic.HibernateDemo3.ivy.util.HibernateUtil;

 public class OpenSessionInViewFilter implements Filter{

     /* (non-Javadoc)

      * @see javax.servlet.Filter#destroy()

      */

     @Override

     public void destroy() {

         // TODO Auto-generated method stub

     }

     /* (non-Javadoc)

      * @see javax.servlet.Filter#doFilter(javax.servlet.ServletRequest, javax.servlet.ServletResponse, javax.servlet.FilterChain)

      */

     @Override

     public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain)

             throws IOException, ServletException {

         /*  事务以及session的关闭    */

         //获取session

         Session session = HibernateUtil.getSession();

         //开启事务

         Transaction tx = session.beginTransaction();

         try {

             chain.doFilter(request, response);

             //提交事务

             tx.commit();

         } catch (HibernateException e) {

             tx.rollback();

             e.printStackTrace();

         } finally {

             //关闭session

             session.close();

         }

     }

     /* (non-Javadoc)

      * @see javax.servlet.Filter#init(javax.servlet.FilterConfig)

      */

     @Override

     public void init(FilterConfig arg0) throws ServletException {

         // TODO Auto-generated method stub

     }

 }

5.dao包
a.IBaseDao

 package com.Elastic.HibernateDemo3.ivy.dao;

 import java.io.Serializable;

 import java.util.List;

 import java.util.Map;

 import com.Elastic.HibernateDemo3.ivy.common.PageList;

 public interface IBaseDao<T> {

     void save(T record);

     //不明确id的类型，就用Serializable

     void delete(Serializable id);

     void update(T record);

     T findById(Serializable id);

     List<T> find(Map<String, Object> params);

     List<T> find(String hql,Map<String, Object> params);

     PageList<T> findByPage(int pageIndex, int pageSize, Map<String, Object> params);

     List<T> findByNamed(String queryName, Map<String, Object> params);

 }

b.BaseDao

 package com.Elastic.HibernateDemo3.ivy.dao;

 import java.io.Serializable;

 import java.lang.reflect.ParameterizedType;

 import java.util.List;

 import java.util.Map;

 import org.hibernate.Query;

 import org.hibernate.Session;

 import com.Elastic.HibernateDemo3.ivy.common.PageList;

 import com.Elastic.HibernateDemo3.ivy.util.HibernateUtil;

 //忽略警告

 @SuppressWarnings({ "rawtypes", "unchecked" })

 public class BaseDao<T> implements IBaseDao<T>{

     private Class entityClass;

     public BaseDao(){

         entityClass = this.getEntityClass();

     }

     /**

      *

      * <p>

      * <h3>方法功能描述：根据反射得到实体类的类型</h3>

      * </p>

      * @return

      * @procedure 执行过程

      * @see BaseDao

      */

     private Class getEntityClass(){

         try {

             ParameterizedType paramsType = (ParameterizedType)this.getClass().getGenericSuperclass();

             return (Class)paramsType.getActualTypeArguments()[0];

         } catch (Exception e) {

             e.printStackTrace();

         }

         return null;

     }

     public Session getSession(){

         return HibernateUtil.getSession();

     }

     @Override

     public void save(T record){

         this.getSession().save(record);

     }

     @Override

     public void delete(Serializable id){

         this.getSession().delete(this.findById(id));

     }

     @Override

     public void update(T record){

         this.getSession().update(record);

     }

     @Override

     public T findById(Serializable id){

         return (T)this.getSession().get(entityClass, id);

     }

     @Override

     public List<T> find(Map<String, Object> params){

         StringBuffer hql = new StringBuffer("from ");

         hql.append(entityClass.getName());

         hql.append(" where 1 = 1 ");

         if (null != params) {

             for (String key : params.keySet()) {

                 hql.append(" and ");

                 hql.append(key);

                 hql.append(" = :");

                 hql.append(key);

             }

         }

         Query query = this.getSession().createQuery(hql.toString());

         if (null != params) {

             query.setProperties(params);

         }

         return query.list();

     }

     @Override

     public List<T> find(String hql, Map<String, Object> params) {

         Query query = this.getSession().createQuery(hql.toString());

         if (null != params) {

             query.setProperties(params);

         }

         return query.list();

     }

     @Override

     public PageList<T> findByPage(int pageIndex, int pageSize, Map<String, Object> params) {

         StringBuffer hql = new StringBuffer("from ");

         hql.append(entityClass.getName());

         hql.append(" where 1 = 1 ");

         if (null != params) {

             for (String key : params.keySet()) {

                 hql.append(" and ");

                 hql.append(key);

                 hql.append(" = :");

                 hql.append(key);

             }

         }

         Query query = this.getSession().createQuery(hql.toString());

         if (null != params) {

             query.setProperties(params);

         }

         //查询总条数

         Query queryTotal = this.getSession().createQuery("select count(*)" + hql.toString());

         if (null != params) {

             queryTotal.setProperties(params);

         }

         int total = Integer.parseInt(queryTotal.uniqueResult().toString());

         //设置分页

         query.setFirstResult((pageIndex - 1) * pageSize);

         query.setMaxResults(pageSize);

         return new PageList<T>(query.list(), pageIndex, pageSize, total);

     }

     /* (non-Javadoc)

      * @see com.Elastic.HibernateDemo3.ivy.dao.IBaseDao#findByNamed(java.lang.String, java.util.Map)

      */

     @Override

     public List<T> findByNamed(String queryName, Map<String, Object> params) {

         Query query = this.getSession().getNamedQuery(queryName);

         return query.setProperties(params).list();

     }

 }

c.DeptDao

 package com.Elastic.HibernateDemo3.ivy.dao;

 import com.Elastic.HibernateDemo3.ivy.entity.Dept;

 public interface DeptDao extends IBaseDao<Dept>{

 }

d.EmpDao

 package com.Elastic.HibernateDemo3.ivy.dao;

 import java.util.List;

 import com.Elastic.HibernateDemo3.ivy.entity.Emp;

 public interface EmpDao extends IBaseDao<Emp> {

     List<Emp> findEmp();

 }

6.dao.impl包
a.DeptDaoImpl

 package com.Elastic.HibernateDemo3.ivy.dao.impl;

 import com.Elastic.HibernateDemo3.ivy.dao.BaseDao;

 import com.Elastic.HibernateDemo3.ivy.dao.DeptDao;

 import com.Elastic.HibernateDemo3.ivy.entity.Dept;

 public class DeptDaoImpl extends BaseDao<Dept> implements DeptDao {

 }

b.EmpDaoImpl

 package com.Elastic.HibernateDemo3.ivy.dao.impl;

 import java.io.Serializable;

 import java.util.List;

 import java.util.Map;

 import com.Elastic.HibernateDemo3.ivy.dao.BaseDao;

 import com.Elastic.HibernateDemo3.ivy.dao.EmpDao;

 import com.Elastic.HibernateDemo3.ivy.entity.Emp;

 public class EmpDaoImpl extends BaseDao<Emp> implements EmpDao {

     /* (non-Javadoc)

      * @see com.Elastic.HibernateDemo3.ivy.dao.EmpDao#findEmp()

      */

     @Override

     public List<Emp> findEmp() {

         this.getSession().getNamedQuery("findEmp"); //配置文件中命名查询的name值

         return null;

     }

 }

7.service包
a.DeptService

 package com.Elastic.HibernateDemo3.ivy.service;

 import java.util.List;

 import java.util.Map;

 import com.Elastic.HibernateDemo3.ivy.common.PageList;

 import com.Elastic.HibernateDemo3.ivy.entity.Dept;

 public interface DeptService{

     List<Dept> searchALLDept();

     List<Dept> searchDeptsByName(String name);

     List<Dept> searchDeptByCondition(Map<String, Object> condition);

     PageList<Dept> searchDeptByPage(int pageIndex, int pageSize, Map<String, Object> condition);

 }

8.service.impl包
a.DeptServiceImpl

 package com.Elastic.HibernateDemo3.ivy.service.impl;

 import java.util.HashMap;

 import java.util.List;

 import java.util.Map;

 import com.Elastic.HibernateDemo3.ivy.common.PageList;

 import com.Elastic.HibernateDemo3.ivy.dao.DeptDao;

 import com.Elastic.HibernateDemo3.ivy.dao.impl.DeptDaoImpl;

 import com.Elastic.HibernateDemo3.ivy.entity.Dept;

 import com.Elastic.HibernateDemo3.ivy.service.DeptService;

 public class DeptServiceImpl implements DeptService {

     private DeptDao deptDao = new DeptDaoImpl();

     /*

      * (non-Javadoc)

      *

      * @see com.Elastic.HibernateDemo3.ivy.service.DeptService#searchALLDept()

      */

     @Override

     public List<Dept> searchALLDept() {

         return deptDao.find(null);

     }

     /*

      * (non-Javadoc)

      *

      * @see

      * com.Elastic.HibernateDemo3.ivy.service.DeptService#searchDeptsByName(java

      * .lang.String)

      */

     @Override

     public List<Dept> searchDeptsByName(String name) {

         Map<String, Object> params = new HashMap<String,Object>();

         params.put("deptName", name);

         return deptDao.find(params);

     }

     @Override

     public List<Dept> searchDeptByCondition(Map<String, Object> condition) {

         return deptDao.find(condition);

     }

     @Override

     public PageList<Dept> searchDeptByPage(int pageIndex, int pageSize, Map<String, Object> condition) {

         return deptDao.findByPage(pageIndex, pageSize, condition);

     }

 }

9.servlet包
a.DeptServlet

 package com.Elastic.HibernateDemo3.ivy.controller;

 import java.io.IOException;

 import java.util.HashMap;

 import java.util.List;

 import java.util.Map;

 import javax.servlet.ServletException;

 import javax.servlet.http.HttpServlet;

 import javax.servlet.http.HttpServletRequest;

 import javax.servlet.http.HttpServletResponse;

 import com.Elastic.HibernateDemo3.ivy.entity.Dept;

 import com.Elastic.HibernateDemo3.ivy.service.DeptService;

 import com.Elastic.HibernateDemo3.ivy.service.impl.DeptServiceImpl;

 /**

  * Servlet implementation class DeptServlet

  */

 public class DeptServlet extends HttpServlet {

     private static final long serialVersionUID = 1L;

     /**

      * @see HttpServlet#HttpServlet()

      */

     public DeptServlet() {

         super();

         // TODO Auto-generated constructor stub

     }

     /**

      * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)

      */

     protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {

         String oper = request.getParameter("oper");

         DeptService deptService = new DeptServiceImpl();

         switch (oper) {

         case "all":

             List<Dept> depts = deptService.searchALLDept();

             request.setAttribute("depts", depts);

             //转发

             request.getRequestDispatcher("/dept.jsp").forward(request, response);

             break;

         case "byName":

             request.setAttribute("depts", deptService.searchDeptsByName(request.getParameter("name")));

             //转发

             request.getRequestDispatcher("/dept.jsp").forward(request, response);

             break;

         case "byCondition":

             //获取页面提交的参数

             String deptName = request.getParameter("deptName");

             String location = request.getParameter("location");

             String id = request.getParameter("deptId");

             //创建保存参数的map集合

             Map<String, Object> condition = new HashMap<String, Object>();

             if (null != deptName && deptName.trim().length() != 0) {

                 //【属性名和页面参数一样要写对！！！】

                 condition.put("deptName", deptName);

             }

             if (null != location && location.trim().length() != 0) {

                 //【属性名和页面参数一样要写对！！！】

                 condition.put("location", location);

             }

             if (null != id && id.trim().length() != 0) {

                 //【属性名和页面参数一样要写对！！！】

                 condition.put("deptId", Integer.parseInt(id));

             }

             String pageIndexString = request.getParameter("pageIndex");

             String pageSizeString = request.getParameter("pageSize");

             int pageIndex = 1;

             int pageSize = 2;

             if (pageIndexString != null && pageIndexString.trim().length() != 0) {

                 pageIndex = Integer.parseInt(pageIndexString);

             }

             if (pageSizeString != null && pageSizeString.trim().length() != 0) {

                 pageSize = Integer.parseInt(pageSizeString);

             }

             request.setAttribute("pageList", deptService.searchDeptByPage(pageIndex, pageSize, condition));

             //转发

             request.getRequestDispatcher("/dept.jsp").forward(request, response);

             break;

         default:

             break;

         }

     }

     /**

      * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)

      */

     protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {

         this.doGet(request, response);

     }

 }

10.common包
a.PageList

 package com.Elastic.HibernateDemo3.ivy.common;

 import java.util.List;

 public class PageList<T> {

     private List<T> data;

     private Integer pageIndex;

     private Integer pageSize;

     private Integer total;

     private Integer pageTotal;

     private Boolean next;

     private Boolean prev;

     public PageList(List<T> data, Integer pageIndex, Integer pageSize, Integer total) {

         super();

         this.data = data;

         this.pageIndex = pageIndex;

         this.pageSize = pageSize;

         this.total = total;

         this.pageTotal = (int)Math.ceil((double)total / pageSize);

         this.next = this.pageIndex < this.pageTotal;

         this.prev = this.pageIndex > 1;

     }

     public List<T> getData() {

         return data;

     }

     public Integer getPageIndex() {

         return pageIndex;

     }

     public Integer getPageSize() {

         return pageSize;

     }

     public Integer getTotal() {

         return total;

     }

     public Integer getPageTotal() {

         return pageTotal;

     }

     public Boolean getNext() {

         return next;

     }

     public Boolean getPrev() {

         return prev;

     }

 }

11.jsp
a.dept.jsp

 <%-- 引入JSP页面PAGE指令 --%>

 <%@ page language="java" contentType="text/html; charset=UTF-8"

     pageEncoding="UTF-8"%>

 <%-- 引入JSTL标签指令 --%>

 <%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %>

 <!DOCTYPE html>

 <html language="zh-CN">

 <head>

     <meta charset="utf-8">

     <!-- 设置浏览器渲染的引擎  -->

     <meta http-equiv="X-UA-Compatible" content="IE=edge,chrome=1">

     <!-- 设置支持移动设备  -->

     <meta name="viewport" content="width=device-width, initial-scale=1">

     <title>网页标题</title>

     <!-- 引用bootstrap样式 -->

     <link rel="stylesheet" type="text/css" href="<%=request.getContextPath() %>/css/bootstrap.min.css">

 </head>

 <body>

     <div class="container-fluid">

         <div class="panel panel-primary">

             <div class="panel-heading"><span class="h3">部门信息</span></div>

             <div class="panel-body">

                 <form action="<%=request.getContextPath()%>/dept/search?oper=byCondition" method="post">

                     <label>部门编号</label>

                     <input name="deptId" type="text"/>

                     <label>部门名称</label>

                     <!-- name与Dept类的属性名一样 -->

                     <input name="deptName" type="text"/>

                     <label>部门位置</label>

                     <input name="location" type="text"/>

                     <input type="hidden" name="pageIndex" value="1"/>

                     <input type="submit" value="搜索" data-toggle="search"/>

                 </form>

             </div>

             <table class="table table-bordered">

                 <thead>

                     <tr>

                         <td>部门编号</td>

                         <td>部门名称</td>

                         <td>部门位置</td>

                         <td>操作</td>

                     </tr>

                 </thead>

                 <tbody>

                     <c:forEach items="${requestScope.pageList.data }" var="dept">

                         <tr>

                             <td>${dept.deptId }</td>

                             <td>${dept.deptName }</td>

                             <td>${dept.location }</td>

                             <td><a class="btn btn-primary btn-xs" href="javascript:;">删除</a></td>

                         </tr>

                     </c:forEach>

                 </tbody>

             </table>

             <div class="panel-footer">

                 <nav>

                   <ul id="deptPage" class="pagination" style="margin: 0px;">

                     <li <c:if test="${not requestScope.pageList.prev }">class="disabled"</c:if>>

                       <a href="#" aria-label="Previous" >

                         <span aria-hidden="true">&laquo;</span>

                       </a>

                     </li>

                     <c:forEach begin="1" end="${requestScope.pageList.pageTotal }" step="1" varStatus="status">

                         <li <c:if test="${status.index eq requestScope.pageList.pageIndex}">class="active"</c:if>>

                              <a href="#">${status.index }</a>

                         </li>

                     </c:forEach>

                     <li <c:if test="${not requestScope.pageList.next }">class="disabled"</c:if>>

                       <a href="#" aria-label="Next">

                         <span aria-hidden="true">&raquo;</span>

                       </a>

                     </li>

                   </ul>

                   <div class="pull-right" style="line-height: 34px;">当前第${requestScope.pageList.pageIndex }页，总共${requestScope.pageList.pageTotal }页</div>

                 </nav>

             </div>

         </div>

     </div>

     <!-- 引用外部JS文件  -->

     <script type="text/javascript" src="<%=request.getContextPath() %>/js/jquery-2.2.4.js"></script>

     <script type="text/javascript" src="<%=request.getContextPath() %>/js/bootstrap.min.js"></script>

     <script type="text/javascript">

         $(function() {

             $('#deptPage').on('click','li > a', function() {

                 if ($(this).closest('li').hasClass('disabled')) {

                     return;

                 }

                 var pageIndex;

                 if ($(this).attr('aria-label') == 'Previous') {

                     pageIndex = parseInt($('#deptPage > li.active > a').text()) - 1;

                 } else if ($(this).attr('aria-label') == 'Next') {

                     pageIndex = parseInt($('#deptPage > li.active > a').text()) + 1;

                 } else {

                     pageIndex = $(this).text();

                 }

                 $('[name="pageIndex"]').val(pageIndex);

                 $('[data-toggle="search"]').trigger('click');

             });

         });

     </script>

 </body>

 </html>