jpa一對多關係無法例外

Question

我想創建填充Admin和AdminHealthPlan表。

兩者之間的關係是一對多關係（一個管理員可以擁有許多健康計劃）。

的Admin類被定義爲如下：

@Entity 
@Table(name = "admin") 
@NamedQueries(value = { 
     @NamedQuery(name = "admin.getAdminById", query = "SELECT a " 
      + "from Admin a WHERE a.id=:id and deleted = 0"), 
     @NamedQuery(name = "admin.getAdminByEmail", query = "SELECT a " 
      + "from Admin a where a.email = :email and deleted = 0") }) 
public class Admin extends Persistent { 

    @Id 
    @GeneratedValue(strategy = GenerationType.AUTO) 
    private Long id; 
    @Column(name = "password") 
    private String password; 
    @Column(name = "email") 
    private String email; 
    @Column(name = "first_name") 
    private String firstName; 
    @Column(name = "last_name") 
    private String lastName; 
    @Column(name = "phone") 
    private String phone; 
    @OneToOne(mappedBy = "admin", fetch = FetchType.EAGER, 
      cascade = CascadeType.ALL) 
    private AdminRole role; 
    @OneToOne(mappedBy = "admin", fetch = FetchType.EAGER, 
      cascade = CascadeType.ALL) 
    private AdminPasswordToken passwordToken; 
    @OneToMany(mappedBy = "admin", fetch = FetchType.EAGER, 
      cascade = CascadeType.ALL) 
    private Set<AdminHealthPlan> healthPlans; 
    @Column(name = "deleted") 
    private Boolean deleted = false; 
    @Column(name = "security_question") 
    private Integer securityQuestion; 
    @Column(name = "security_answer") 
    private String securityAnswer; 

    public Admin() {} 

    // Getters/setters 
} 

AdminHealthPlan類定義如下。

@Entity 
@Table(name = "admin_health_plan") 
public class AdminHealthPlan implements Serializable { 

    private static final long serialVersionUID = 1L; 
    @Id 
    @GeneratedValue(strategy = GenerationType.AUTO) 
    private Long id; 
    @Column(name = "health_plan") 
    private String healthPlan; 
    @ManyToOne(cascade = CascadeType.ALL) 
    @JoinColumn(name = "admin_id", nullable = false) 
    private Admin admin; 
    @Column(name = "deleted") 
    private Boolean deleted = false; 

    public AdminHealthPlan() {} 

    public AdminHealthPlan(String healthPlan) { 
     this.healthPlan = healthPlan; 
    } 

    // Getters/setters 
} 

我從請求檢索值並將其設置爲管理對象，同樣用於創建管理健康計劃設置對象和管理對象設置它，最後發送對象保存到數據庫創建管理對象。

它給例外如下

May 21, 2012 6:49:16 PM org.apache.catalina.core.StandardWrapperValve invoke 
SEVERE: Servlet.service() for servlet appServlet threw exception 
com.mysql.jdbc.exceptions.jdbc4.MySQLIntegrityConstraintViolationException: Column 'admin_id' cannot be null 
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) 
    at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:39) 
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27) 
    at java.lang.reflect.Constructor.newInstance(Constructor.java:513) 
    at com.mysql.jdbc.Util.handleNewInstance(Util.java:406) 
    at com.mysql.jdbc.Util.getInstance(Util.java:381) 
    at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:1015) 
    at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:956) 
    at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3558) 
    at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3490) 
    at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:1959) 
    at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2109) 
    at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2648) 
    at com.mysql.jdbc.PreparedStatement.executeInternal(PreparedStatement.java:2077) 
    at com.mysql.jdbc.PreparedStatement.executeUpdate(PreparedStatement.java:2362) 
    at com.mysql.jdbc.PreparedStatement.executeUpdate(PreparedStatement.java:2280) 
    at com.mysql.jdbc.PreparedStatement.executeUpdate(PreparedStatement.java:2265) 
    at org.apache.tomcat.dbcp.dbcp.DelegatingPreparedStatement.executeUpdate(DelegatingPreparedStatement.java:105) 
    at org.apache.tomcat.dbcp.dbcp.DelegatingPreparedStatement.executeUpdate(DelegatingPreparedStatement.java:105) 
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) 
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39) 
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25) 
    at java.lang.reflect.Method.invoke(Method.java:597) 
    at org.hibernate.engine.jdbc.internal.proxy.AbstractStatementProxyHandler.continueInvocation(AbstractStatementProxyHandler.java:122) 
    at org.hibernate.engine.jdbc.internal.proxy.AbstractProxyHandler.invoke(AbstractProxyHandler.java:81) 
    at $Proxy70.executeUpdate(Unknown Source) 

WS

創建管理員和AdminHealthPlan對象：

private Admin createAdminDummyObject() { 
     Admin admin = new Admin(); 
     admin.setFirstName("Zuned"); 
     admin.setLastName("Ahmed"); 
     admin.setEmail("zuned@hcentive.com"); 
     admin.setPhone("123-1234454"); 
     admin.setHealthPlans(getHealthPlans(admin)); 
     return admin; 
    } 

    private Set<AdminHealthPlan> getHealthPlans(Admin admin) { 
     Set<AdminHealthPlan> adminAHP = new HashSet<AdminHealthPlan>(); 
     AdminHealthPlan ahp = new AdminHealthPlan(); 
     ahp.setAdmin(admin); 
     ahp.setHealthPlan("Plan1"); 
     adminAHP.add(ahp); 
     return adminAHP; 
    } 

我用

getJpaTemplate().persist(t); 

堅持分貝。

任何機構可以告訴我我錯過了什麼嗎？

Answer 1

我將EclipseLink，所以我不知道，如果它這樣做在休眠不同，但是這是我所看到的錯誤：

1 - 你沒有@Column批註添加到的id屬性管理實體。
2 - 我始終對pks使用GenerationType.IDENTITY。 3 - 在AdminHealthPlan表中，admin屬性具有JoinColumn註釋，但未包含referencedColumnName屬性。它應該是這樣的：@JoinColumn(name = "admin_id", referencedColumnName = "admin_id")
4-添加新AdminHealthPlan到管理實體，我建議你做到以下幾點：創建一個名爲「addAdminHealthPlan」管理類中的方法：

public void addAdminHealthPlan(AdminHealthPlan ahp) { 
    if(healthPlans == null) { 
      healthPlans = new HashSet<AdminHealthPlan>(); 
    } 
    ahp.setAdmin(this); 
    healthPlans.add(ahp); 
} 

我不t知道什麼是getJpaTemplate（）方法和什麼是對象「t」，但這將是堅持管理員的邏輯：

Admin admin = createAdminDummyObject(); 
AdminHealthPlan ahp = new AdminHealthPlan(); 
ahp.setAdmin(admin); 
ahp.setHealthPlan("Plan1"); 
admin.addAdminHealthPlan(ahp); 
entityManager.persist(admin);