是这样，
我做了个映射类该类是这样写的，该映射用到复合主键
public class DriverLoginoffInfo implements java.io.Serializable{
public DriverLoginoffInfo()
{
}
//司机登录退出的复合主键
private DriverLoginoffId driverId;

//退出时间
private Date logoffTime;

//司机信息
private Driverinfo driverInfo = new Driverinfo();
/**
* @return the driverId
*/
public DriverLoginoffId getDriverId() {
return driverId;
}
/**
* @param driverId the driverId to set
*/
public void setDriverId(DriverLoginoffId driverId) {
this.driverId = driverId;
}
/**
* @return the logoffTime
*/
public Date getLogoffTime() {
return logoffTime;
}
/**
* @param logoffTime the logoffTime to set
*/
public void setLogoffTime(Date logoffTime) {
this.logoffTime = logoffTime;
}
/**
* @return the driverInfo
*/
public Driverinfo getDriverInfo() {
return driverInfo;
}
/**
* @param driverInfo the driverInfo to set
*/
public void setDriverInfo(Driverinfo driverInfo) {
this.driverInfo = driverInfo;
}

}

复合主键的类
public class DriverLoginoffId implements java.io.Serializable{

public DriverLoginoffId()
{

}
//农机编号
private String equipId;
//司机工号
private String driverCode;
//登录时间
private Date loginTime;
/**
* @return the equipId
*/
public String getEquipId() {
return equipId;
}
/**
* @param equipId the equipId to set
*/
public void setEquipId(String equipId) {
this.equipId = equipId;
}
/**
* @return the driverCode
*/
public String getDriverCode() {
return driverCode;
}
/**
* @param driverCode the driverCode to set
*/
public void setDriverCode(String driverCode) {
this.driverCode = driverCode;
}
/**
* @return the loginTime
*/
public Date getLoginTime() {
return loginTime;
}
/**
* @param loginTime the loginTime to set
*/
public void setLoginTime(Date loginTime) {
this.loginTime = loginTime;
}

}

而DriverLoginoffInfo类映射为
<hibernate-mapping package="com.navchina.domain.driverworktimestat">
<class name="DriverLoginoffInfo"
   table="T_LOGINOFF"
   schema="AGRI">
   <composite-id name="driverId" class="DriverLoginoffId">
   <key-property name="equipId" type="java.lang.String">
   <column name="EQUIPCODE" length="10"/>
   </key-property>
   <key-property name="driverCode" type="java.lang.String">
   <column name="DRIVERID" length="10"/>
    </key-property>
    <key-property name="loginTime" type="java.util.Date">
    <column name="LOGINTIME"/>
    </key-property>
   </composite-id>
   <property name="logoffTime" type="java.util.Date">
   <column name="LOGOFFTIME"/>
   </property>
   <many-to-one name="driverInfo"
                class="com.navchina.domain.drivermanage.Driverinfo"
                update="false"
                insert="false"
                fetch="select">
   <column name="DRIVERID"
           length="10"
           not-null="true"/>
   </many-to-one>
</class>
</hibernate-mapping>

driverInfo是DriverLoginoffInfo的一个关联的表，外键位DRIVERID
driverInfo的类是
import java.util.Date;

import com.navchina.domain.organmanage.OrganInfo;

public class Driverinfo {
// 司机工号
private String driverId;
// 司机名称
private String driverName;

// 单位组织
private String organCode;
private OrganInfo organInfo = new OrganInfo();
// email
private String email;
// 创建人
private String createUser;
// 创建时间
private Date createDate;
// 修改人
private String modUser;
// 修改时间
private Date modDate;
// 是否有效0：失效、1：有效
private String isValid;
public String getDriverId() {
return driverId;
}
public void setDriverId(String driverId) {
this.driverId = driverId;
}
public String getDriverName() {
return driverName;
}
public void setDriverName(String driverName) {
this.driverName = driverName;
}
public OrganInfo getOrganInfo() {
return organInfo;
}
public void setOrganInfo(OrganInfo organInfo) {
this.organInfo = organInfo;
}
public String getEmail() {
return email;
}
public void setEmail(String email) {
this.email = email;
}
public String getCreateUser() {
return createUser;
}
public void setCreateUser(String createUser) {
this.createUser = createUser;
}
public Date getCreateDate() {
return createDate;
}
public void setCreateDate(Date createDate) {
this.createDate = createDate;
}
public String getModUser() {
return modUser;
}
public void setModUser(String modUser) {
this.modUser = modUser;
}
public Date getModDate() {
return modDate;
}
public void setModDate(Date modDate) {
this.modDate = modDate;
}
public String getIsValid() {
return isValid;
}
public void setIsValid(String isValid) {
this.isValid = isValid;
}
public void setOrganCode(String organCode) {
this.organCode = organCode;
}
public String getOrganCode() {
return organCode;
}

}

Driverinfo 的映射
<hibernate-mapping package="com.navchina.domain.drivermanage">
<class name="Driverinfo"
   table="T_DRIVERINFO">
<id name="driverId"
type="java.lang.String">
<column name="DRIVERID"
length="10"/>
<generator class="assigned"/>
</id>
<property name="driverName"
  type="java.lang.String">
<column name="DRIVERNAME"
length="20"
not-null="true"/>
</property>
<property name="organCode"
  type="java.lang.String">
<column name="ORGANCODE"
length="20"
not-null="true"/>
</property>
<many-to-one name="organInfo"
class="com.navchina.domain.organmanage.OrganInfo"
update="false"
insert="false"
fetch="select">
<column name="ORGANCODE"
length="20"
not-null="true"/>
</many-to-one>
<property name="email"
  type="java.lang.String">
<column name="EMAIL"
length="40"
not-null="false"/>
</property>
<property name="createUser"
  type="java.lang.String">
<column name="CREATEUSER"
length="10"/>
</property>
<property name="createDate"
  type="java.util.Date">
<column name="CREATEDATE"
length="7"/>
</property>
<property name="modUser"
  type="java.lang.String">
<column name="MODUSER"
length="10"/>
</property>
<property name="modDate"
  type="java.util.Date">
<column name="MODDATE"
length="7"/>
</property>
<property name="isValid"
  type="java.lang.String">
<column name="ISVALID"
length="1"
not-null="true"/>
</property>
</class>
</hibernate-mapping>
该类里还有另一个表organInfo的表相关联

但是查的时候organInfo表里的东西查不出来，是什么原因，是不是hibernate不支持嵌套两张表的查询？