Java – @ stateless WebService with JPA JTA: how to submit changes to managed entities?

I have the following simple WebService declared as @ freeless EJB in GlassFish 3.1 Run on 2.2, eclipse link 2.4 1. Use JTA datasource to connect to MySQL database:

@POST
@Consumes(MediaType.APPLICATION_JSON)
public Response update(TimeRow e) throws Exception {
    if ((e.getKey() == null) || !e.getKey().keyValid()) {
        return Response.status(400).build();
    }

    TimeRow existing = em.find(TimeRow.class,e.getKey());
    if (existing == null) {
        em.persist(e);
    } else {
        existing.setValues(e.getValues());
        em.flush();
    }
    return Response.status(204).build();
}

Entity class of timerow:

@Entity
@NamedQueries({
    @NamedQuery(name="TimeRow.findAllByUser",query="SELECT t FROM TimeRow t WHERE t.table.userId = :uid")
})
public class TimeRow implements Serializable {

    @EmbeddedId
    private TimeRowPK key;

    @MapsId("userId")
    @JoinColumn(name = "USERID",referencedColumnName = "userId")
    @ManyToOne
    private UserTable table;
    @Column(name="ROWVALUES")
    private List<Double> values;

    public TimeRow() {
        this.key = new TimeRowPK();
        this.values = new ArrayList<Double>(20);
        extendValuesTo20();
    }

    public TimeRow(String uid,Date date) {
        this.key = new TimeRowPK(date,uid);
        this.table = new UserTable(uid);
        this.values = new ArrayList<Double>(20);
        extendValuesTo20();
    }

    public List<Double> getValues() {
        return values;
    }

    public void setValues(List<Double> values) {
        this.values = values;
        extendValuesTo20();
    }

    private void extendValuesTo20() {
        if (this.values.size() < 20) {
             for (int i = this.values.size(); i < 20; i++) {
                  this.values.add(0.0);
             }
        }
    }

}

@EmbeddableId TimeRowPK:

@Embeddable
public class TimeRowPK implements Serializable {

    public TimeRowPK() { }

    public TimeRowPK(Date date,String userId) {
        this.date = date;
        this.userId = userId;
    }

    @Column(name="DAY")
    private Date date;
    @Column(name = "USERID")
    private String userId;

    public boolean keyValid() {
        return ((date != null) && ((userId != null) && !userId.isEmpty()));
    }

}

persistence. XML (no < persistence > tag):

<persistence-unit name="test" transaction-type="JTA">
    <provider>org.eclipse.persistence.jpa.PersistenceProvider</provider>
    <jta-data-source>jdbc/test</jta-data-source>
    <class>com.test.TimeRow</class>
    <class>com.test.TimeRowPK</class>
    <class>...</class>
    <properties>
        <property name="eclipselink.ddl-generation" value="create-tables" />
        <property name="eclipselink.ddl-generation.output-mode" value="database" />
    </properties>
</persistence-unit>

Web service declaration:

@Path("row")
@Stateless
public class TimeRowWebService {

    @PersistenceContext(unitName = "test")
    private EntityManager em;

    ...

}

The problem is that if entities exist, changes are only stored in the persistencecontext, but they are not committed to the database This means that I can use the changes to retrieve the correct data, but for example, if I restart as, the changes will disappear There are no errors in the as log

So I think I have to do some bean level manual transactions to do this What exactly do I need to add to make it work?

Solution

After trying to make @ embeddedid work, I try to implement it with the generated @ ID, and then add a unique constraint for these two key fields

entity

public class TimeRow implements Serializable {

    @Id
    @GeneratedValue
    private long id;

    @JoinColumn(name = "USERID",referencedColumnName = "USERID")
    @ManyToOne(optional = false)
    private UserTable table;

    @Basic(optional = false)
    @Column(name = "DAY")
    @Temporal(TemporalType.DATE)
    private Date date;

    @Lob
    @Column(name="ROWVALUES")
    private List<Double> values;

    ...
}

In addition, I have changed the database engine from MyISAM to InnoDB for better foreign key support To this end, I added default storage engine = InnoDB to / etc / MySQL / my. Under the [mysqld] section cnf.

After generating the database structure using DDL, I have added a unique constraint for userid and day:

alter table TIMEROW add unique index(USERID,DAY);

Now it works normally and the data has been modified correctly:) thank you very much to all those who have contributed to this problem!

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