使用hibernate时如果提示映射不对时可能是以下原因

根据HQL得到一个数据对象时出错：ZYExam is not mapped [From ZYExam AS z WHERE z.lZhuanYeId = 4 AND z.lExamInfoId=1718]; nested exception is org.hibernate.hql.ast.QuerySyntaxException: ZYExam is not mapped [From ZYExam AS z WHERE z.lZhuanYeId = 4 AND z.lExamInfoId=1718]

package net.pthl.SAASProduct.entity;
 
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.Table;
 
import javacommon.core.base.BaseEntity;
 
/**
 * 1:---专业考试表/多对多关系。
 * 2:---自己维护：---因为要在表中加个成绩字段/维护成绩
 * 
 * @author wangchh
 *
 */
@Entity(name = "ZY_Exam")
@Table(name = "ZY_Exam")
public class ZYExam extends BaseEntity
{
	/**
	 * 序列化ID。
	 */
	private static final long serialVersionUID = 8295041166614311961L;
 
	/**
	 * 字段常量信息。
	 */
	public static final String ID = "lId";
	public static final String ZYID = "lZhuanYeId";
	public static final String EID = "lExamInfoId";
	public static final String SCORE = "strScore";
	public static final String SCORE_STATUS = "nScoreStatus";
	public static final String RESERVER1 = "strReserver1";
	public static final String RESERVER2 = "strReserver2";
	public static final String RESERVER3 = "strReserver3";
	public static final String RESERVER4 = "strReserver4";
	
	@Id
	@GeneratedValue(strategy = GenerationType.IDENTITY)
	@Column(name = "ID", nullable = false)
	private Long lId;// 专业考试表ID
	
	@Column(name = "ZYID", nullable = false)
	private Long lZhuanYeId;// ZhuanYe ID
	
	@Column(name = "EID", nullable = false)
	private Long lExamInfoId;// ExamInfo ID
	
	@Column(name = "Score")
	private String strScore;// 成绩
	
	@Column(name = "Score_Status", nullable = false)
	private int nScoreStatus;// 成绩申报的状态；未申报:0；已申报:1
	
	/**
	 * 备用字段，用于扩展。
	 */
	@Column(name = "reserver1")
	private String strReserver1;
 
	/**
	 * 备用字段，用于扩展。
	 */
	@Column(name = "reserver2")
	private String strReserver2;
 
	/**
	 * 备用字段，用于扩展。
	 */
	@Column(name = "reserver3")
	private String strReserver3;
 
	/**
	 * 备用字段，用于扩展。
	 */
	@Column(name = "reserver4")
	private String strReserver4;
 
	/**
	 * 获取lId。
	 *
	 * @return the lId
	 */
	public Long getLId()
	{
		return lId;
	}
 
	/**
	 * 设置lId。
	 *
	 * @param lId the lId to set
	 */
	public void setLId(Long lId)
	{
		this.lId = lId;
	}
 
	/**
	 * 获取lZhuanYeId。
	 *
	 * @return the lZhuanYeId
	 */
	public Long getLZhuanYeId()
	{
		return lZhuanYeId;
	}
 
	/**
	 * 设置lZhuanYeId。
	 *
	 * @param lZhuanYeId the lZhuanYeId to set
	 */
	public void setLZhuanYeId(Long lZhuanYeId)
	{
		this.lZhuanYeId = lZhuanYeId;
	}
 
	/**
	 * 获取lExamInfoId。
	 *
	 * @return the lExamInfoId
	 */
	public Long getLExamInfoId()
	{
		return lExamInfoId;
	}
 
	/**
	 * 设置lExamInfoId。
	 *
	 * @param lExamInfoId the lExamInfoId to set
	 */
	public void setLExamInfoId(Long lExamInfoId)
	{
		this.lExamInfoId = lExamInfoId;
	}
 
	/**
	 * 获取strScore。
	 *
	 * @return the strScore
	 */
	public String getStrScore()
	{
		return strScore;
	}
 
	/**
	 * 设置strScore。
	 *
	 * @param strScore the strScore to set
	 */
	public void setStrScore(String strScore)
	{
		this.strScore = strScore;
	}
 
	/**
	 * 获取scoreStatus。
	 *
	 * @return the scoreStatus
	 */
	public int getNScoreStatus()
	{
		return nScoreStatus;
	}
 
	/**
	 * 设置scoreStatus。
	 *
	 * @param nScoreStatus the scoreStatus to set
	 */
	public void setNScoreStatus(int nScoreStatus)
	{
		this.nScoreStatus = nScoreStatus;
	}
 
	/**
	 * 获取strReserver1。
	 *
	 * @return the strReserver1
	 */
	public String getStrReserver1()
	{
		return strReserver1;
	}
 
	/**
	 * 设置strReserver1。
	 *
	 * @param strReserver1 the strReserver1 to set
	 */
	public void setStrReserver1(String strReserver1)
	{
		this.strReserver1 = strReserver1;
	}
 
	/**
	 * 获取strReserver2。
	 *
	 * @return the strReserver2
	 */
	public String getStrReserver2()
	{
		return strReserver2;
	}
 
	/**
	 * 设置strReserver2。
	 *
	 * @param strReserver2 the strReserver2 to set
	 */
	public void setStrReserver2(String strReserver2)
	{
		this.strReserver2 = strReserver2;
	}
 
	/**
	 * 获取strReserver3。
	 *
	 * @return the strReserver3
	 */
	public String getStrReserver3()
	{
		return strReserver3;
	}
 
	/**
	 * 设置strReserver3。
	 *
	 * @param strReserver3 the strReserver3 to set
	 */
	public void setStrReserver3(String strReserver3)
	{
		this.strReserver3 = strReserver3;
	}
 
	/**
	 * 获取strReserver4。
	 *
	 * @return the strReserver4
	 */
	public String getStrReserver4()
	{
		return strReserver4;
	}
 
	/**
	 * 设置strReserver4。
	 *
	 * @param strReserver4 the strReserver4 to set
	 */
	public void setStrReserver4(String strReserver4)
	{
		this.strReserver4 = strReserver4;
	}
 
	/**
	 * 获取lId。
	 *
	 * @return the lId
	 */
	public Long getlId()
	{
		return lId;
	}
 
	/**
	 * 设置lId。
	 *
	 * @param lId the lId to set
	 */
	public void setlId(Long lId)
	{
		this.lId = lId;
	}
 
	/**
	 * 获取lZhuanYeId。
	 *
	 * @return the lZhuanYeId
	 */
	public Long getlZhuanYeId()
	{
		return lZhuanYeId;
	}
 
	/**
	 * 设置lZhuanYeId。
	 *
	 * @param lZhuanYeId the lZhuanYeId to set
	 */
	public void setlZhuanYeId(Long lZhuanYeId)
	{
		this.lZhuanYeId = lZhuanYeId;
	}
 
	/**
	 * 获取lExamInfoId。
	 *
	 * @return the lExamInfoId
	 */
	public Long getlExamInfoId()
	{
		return lExamInfoId;
	}
 
	/**
	 * 设置lExamInfoId。
	 *
	 * @param lExamInfoId the lExamInfoId to set
	 */
	public void setlExamInfoId(Long lExamInfoId)
	{
		this.lExamInfoId = lExamInfoId;
	}
 
	/**
	 * 获取nScoreStatus。
	 *
	 * @return the nScoreStatus
	 */
	public int getnScoreStatus()
	{
		return nScoreStatus;
	}
 
	/**
	 * 设置nScoreStatus。
	 *
	 * @param nScoreStatus the nScoreStatus to set
	 */
	public void setnScoreStatus(int nScoreStatus)
	{
		this.nScoreStatus = nScoreStatus;
	}
	
}

这个类中上面的@Entity(name = "ZY_Exam")与你的From后面的类名不对应的问题。

strHql = "From ZYExam AS z WHERE z.lZhuanYeId = " + objZhuanYe.getlId() + " AND z.lExamInfoId=" + objExamInfo.getlId();