org.hibernate.MappingException: Unknown entity

在dao层查询出现该问题的个人有以下原因
1.在hibernate配置文件中要加入对应实体类

	
	
		
			com.copa.model.AaClass
		
	
	
		
			org.hibernate.dialect.MySQLDialect
			false
			false
		
	

2.实体类中注意标注对应的注解（否则无法识别）
如下所示

@Entity
@Table(name = "copa_table")
public class AaClass implements Serializable {
	
	private static final long serialVersionUID = 1L;

	@Id
	@GeneratedValue(strategy = GenerationType.IDENTITY)
	@Column(name = "id", unique = true, nullable = false, insertable = true, updatable = true, precision = 20, scale = 0)
	private Long id;
}

3.导入上述注解注意包名前缀

javax.persistence.

注意别导错包！