使用JPA

Question

写一个请求

如何使用JPA请求通过给定的平台名称检索环境名称（1个环境可以关联到n Plateform和1 Platform可以关联到n Environmnt）？

public class HPe implements Serializable { 
private static final long serialVersionUID = 1L; 
@EmbeddedId 
protected HPePK hPePK; 
@Column(name = "PE_TIMEOUT") 
private Integer peTimeout; 
@Column(name = "PE_STATUS") 
private Boolean peStatus; 
@OneToMany(cascade = CascadeType.ALL, mappedBy = "hPe") 
private Collection<HPesp> hPespCollection; 
@JoinColumn(name = "PE_ENV", referencedColumnName = "ENV_URL", insertable = false, updatable = false) 
@ManyToOne(optional = false) 
private HEnv hEnv; // HEnv classe name 
@JoinColumn(name = "PE_PLATFORM", referencedColumnName = "PLATFORM_NAME", insertable = false, updatable = false) 
@ManyToOne(optional = false) 
private HPlatform hPlatform; //HPlatform classe name 
} 

更新 问题Resloved：

SELECT h.hPePK.peEnv FROM HPE H其中h.hPePK.pePlatform =：W

Answer 1

请尝试

select hpe.hEnv.envName from HPe hpe where hpe.hPlatform.platName = :platName 

（使用platName作为参数）

也许它需要更多的东西ike a join但是请先尝试