7

両方のテーブルが自動インクリメントを使用するように質問を更新しました。おそらくテーブルへの永続化MESSAGESの問題は、データベース スキーマの問題でしょうか?

MessageBean を永続化しようとすると、次のようになります。

private void persist(MessageBean messageBean) throws Exception {
    LOG.info("loading.." + messageBean);

    Messages message = new Messages(messageBean);

    emf = Persistence.createEntityManagerFactory("USENETPU");
    em = emf.createEntityManager();

    em.getTransaction().begin();
    em.persist(message);
    em.getTransaction().commit();
}

スタックトレース：

run:
Jul 27, 2012 3:04:06 PM net.bounceme.dur.usenet.controller.CommentsDefaultListModel persist
INFO: loading..floor installer (cultas lake)
[EL Info]: 2012-07-27 15:04:10.006--ServerSession(30409723)--EclipseLink, version: Eclipse Persistence Services - 2.3.0.v20110604-r9504
[EL Info]: 2012-07-27 15:04:11.78--ServerSession(30409723)--file:/home/thufir/NetBeansProjects/USENET/build/classes/_USENETPU login successful
[EL Warning]: 2012-07-27 15:04:12.072--ClientSession(29574192)--Exception [EclipseLink-4002] (Eclipse Persistence Services - 2.3.0.v20110604-r9504): org.eclipse.persistence.exceptions.DatabaseException
Internal Exception: com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: Table 'nntp.SEQUENCE' doesn't exist
Error Code: 1146
Call: UPDATE SEQUENCE SET SEQ_COUNT = SEQ_COUNT + ? WHERE SEQ_NAME = ?
    bind => [2 parameters bound]
Query: DataModifyQuery(name="SEQUENCE" sql="UPDATE SEQUENCE SET SEQ_COUNT = SEQ_COUNT + ? WHERE SEQ_NAME = ?")
Jul 27, 2012 3:04:12 PM net.bounceme.dur.usenet.controller.CommentsDefaultListModel <init>
SEVERE: null
Local Exception Stack: 
Exception [EclipseLink-4002] (Eclipse Persistence Services - 2.3.0.v20110604-r9504): org.eclipse.persistence.exceptions.DatabaseException
Internal Exception: com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: Table 'nntp.SEQUENCE' doesn't exist
Error Code: 1146
Call: UPDATE SEQUENCE SET SEQ_COUNT = SEQ_COUNT + ? WHERE SEQ_NAME = ?
    bind => [2 parameters bound]
Query: DataModifyQuery(name="SEQUENCE" sql="UPDATE SEQUENCE SET SEQ_COUNT = SEQ_COUNT + ? WHERE SEQ_NAME = ?")
    at org.eclipse.persistence.exceptions.DatabaseException.sqlException(DatabaseException.java:324)

MySql から:

mysql> 
mysql> 
mysql> show tables;
+----------------+
| Tables_in_nntp |
+----------------+
| comments       |
| messages       |
+----------------+
2 rows in set (0.00 sec)

mysql> 
mysql> show create table comments;
+----------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| Table    | Create Table                                                                                                                                                                                                                                                                                                                                  |
+----------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| comments | CREATE TABLE `comments` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `message_id` int(11) NOT NULL,
  `comment` text NOT NULL,
  `stamp` date NOT NULL,
  PRIMARY KEY (`id`),
  KEY `message_id` (`message_id`),
  CONSTRAINT `comments_ibfk_1` FOREIGN KEY (`message_id`) REFERENCES `messages` (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=latin1 |
+----------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
1 row in set (0.00 sec)

mysql> 
mysql> show create table messages;
+----------+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| Table    | Create Table                                                                                                                                                                                                                               |
+----------+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| messages | CREATE TABLE `messages` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `newsgroup` text NOT NULL,
  `subject` text NOT NULL,
  `content` text NOT NULL,
  `number` text NOT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=latin1 |
+----------+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
1 row in set (0.00 sec)

mysql>

およびメッセージのフィールド:

package net.bounceme.dur.usenet.controller;

import java.io.Serializable;
import java.util.Collection;
import javax.persistence.*;
import javax.xml.bind.annotation.XmlRootElement;
import javax.xml.bind.annotation.XmlTransient;

@Entity
@Table(name = "messages", catalog = "nntp", schema = "")
@XmlRootElement
@NamedQueries({
    @NamedQuery(name = "Messages.findAll", query = "SELECT m FROM Messages m"),
    @NamedQuery(name = "Messages.findById", query = "SELECT m FROM Messages m WHERE m.id = :id")})
public class Messages implements Serializable {
    private static final long serialVersionUID = 1L;
    @Id
    @Basic(optional = false)
    @Column(name = "id", nullable = false)
    @GeneratedValue
    private Integer id;
    @Basic(optional = false)
    @Lob
    @Column(name = "newsgroup", nullable = false, length = 65535)
    private String newsgroup;
    @Basic(optional = false)
    @Lob
    @Column(name = "subject", nullable = false, length = 65535)
    private String subject;
    @Basic(optional = false)
    @Lob
    @Column(name = "content", nullable = false, length = 65535)
    private String content;
    @Basic(optional = false)
    @Lob
    @Column(name = "number", nullable = false, length = 65535)
    private String number;
    @OneToMany(cascade = CascadeType.ALL, mappedBy = "messageId")
    private Collection<Comments> commentsCollection;

    public Messages() {
    }

コメント フィールド:

package net.bounceme.dur.usenet.controller;

import java.io.Serializable;
import java.util.Date;
import javax.persistence.*;
import javax.xml.bind.annotation.XmlRootElement;

@Entity
@Table(name = "comments", catalog = "nntp", schema = "")
@XmlRootElement
@NamedQueries({
    @NamedQuery(name = "Comments.findAll", query = "SELECT c FROM Comments c"),
    @NamedQuery(name = "Comments.findById", query = "SELECT c FROM Comments c WHERE c.id = :id"),
    @NamedQuery(name = "Comments.findByStamp", query = "SELECT c FROM Comments c WHERE c.stamp = :stamp")})
public class Comments implements Serializable {

    private static final long serialVersionUID = 1L;
    @Id
    @Basic(optional = false)
    @Column(name = "id", nullable = false)
    @GeneratedValue
    private Integer id;
    @Basic(optional = false)
    @Lob
    @Column(name = "comment", nullable = false, length = 65535)
    private String comment;
    @Basic(optional = false)
    @Column(name = "stamp", nullable = false)
    @Temporal(TemporalType.DATE)
    private Date stamp;
    @JoinColumn(name = "message_id", referencedColumnName = "id", nullable = false)
    @ManyToOne(optional = false)
    private Messages messageId;

    public Comments() {
    }
4

2 に答える 2

23

次のことをおmysql勧めします。

あなたのテーブルmessagesでフィールドidに宣言を追加しますauto_increment：

create table messages(
...
id  int not null auto_increment,
...
primary key (id)
)

実体宣言使用時

@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
private int id;

これは JPA と対話し、MySQL の自動インクリメント機能を使用します

適用できない場合 (たとえば、同じトランザクションで関連する別のエンティティを作成する場合) は、TABLE 戦略を使用します (詳細については、http://www.objectdb.com/java/jpa/entity/generatedを参照してください) 。

于 2012-07-26T14:28:22.487 に答える