没有基础表的休眠实体

我们一直在做这种事情-这是我们的做事方式：

1. 定义一个简单的类似于bean的对象来表示报告中的每一行输出：

   public class CityStateRevenueReport {private String mId;private String mState;private String mCity;private Double mRevenue;public String getId() { return mId; }public void setId(String i) { mId = i; }public String getState() { return mState; }public void setState(String s) { mState = s; }public String getCity() { return mCity; }public void setCity(String c) { mCity = c; }public Double getReveneue() { return mRevenue; }public void setRevneue(Double d) { mRevenue = d; }

   }

2. 定义一个hibernate映射文件CityStateRevneueReport.hbm.xml：

       <?xml version="1.0" ?>    <!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN" "http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd&quot;>    <hibernate-mapping>        <class entity-name="CityStateRevenueReport"> <id name="Id" type="java.lang.String" column="report_id">     <generator  /> </id> <property name="city" type="string" column="city" /> <property name="state" type="string" column="state" /> <property name="revenue" type="double" column="revenue" />        </class>        <sql-query name="runReport"> <![CDATA[  SELECt {r.*} FROM      (select some_id_value as report_id,   state_abbreviation as state,   city_name as city,   dollar_amount as revenue         from -- tables, joins, other SQL insanity       ) r ]]> <return alias="r"  />        </sql-query>    </hibernate-mapping>

1. 然后运行查询并填充实例：

   public List<CityStateRevenueReport> runReport() {List<CityStateRevenueReport> reports =    new ArrayList<CityStateRevenueReport>();List<HashMap> maps = session.getNamedQuery("runReport").list()for ( HashMap map : results ) {    CityStateRevenueReport report = new CityStateRevenueReport();    report.setState(map.get("state"));    report.setCity(map.get("city"));    report.setRevenue(Double.parseDouble(map.get("revenue"));    reports.add(report);}return reports;

   }