Java Class Generation with schema for DB2 mismatch

etienne · **Posted:** Tue Apr 12, 2005 2:45 pm

Hi,

I am using the latest Artifact Extractor in Eclispe 3.1M5 to build the Hibernate XML mapping (hbm.xml) and the java Pojo classes. For testing purpose, I am doing the extraction on a MySQL database. And I have this strange issue, the java Pojo set most field like java.lang.Character, but it should be set as String. It seems that all DB table column set as Char(##) are transpose as a java.lang.Character in the Pojo... Is that a Bug?

Here the database ddl:

Code:

create table GNDIVI00 (
     DIDIVI               CHAR(6)                        default ' ' not null,
     DINOM                CHAR(40)                       default ' ' not null,
     DIUSAR               CHAR(10)                       default ' ' not null,
     DIREST               CHAR(1)                        default ' ' not null,
     DIDATC               NUMERIC(8)                     default 0 not null,
     DIHRSC               NUMERIC(4)                     default 0 not null,
     DIUSAC               CHAR(10)                       default ' ' not null,
     DIDATM               NUMERIC(8)                     default 0 not null,
     DIHRSM               NUMERIC(4)                     default 0 not null,
     DIUSAM               CHAR(10)                       default ' ' not null,
     constraint PK_GNDIVI00 primary key (DIDIVI)
)

here the the Pojo:

Code:

// default package


/**
 * Gndivi00 generated by hbm2java
 */
public class Gndivi00  implements java.io.Serializable {

    // Fields    

    private java.lang.Character Didivi;
    private java.lang.Character Dinom;
    private java.lang.Character Diusar;
    private java.lang.Character Direst;
    private java.math.BigDecimal Didatc;
    private java.math.BigDecimal Dihrsc;
    private java.lang.Character Diusac;
    private java.math.BigDecimal Didatm;
    private java.math.BigDecimal Dihrsm;
    private java.lang.Character Diusam;


    // Constructors

    /** default constructor */
    public Gndivi00() {
    }
    
    /** constructor with id */
    public Gndivi00(java.lang.Character Didivi) {
        this.Didivi = Didivi;
    }
    
    

    // Property accessors
    /**
     */
   public java.lang.Character getDidivi () {
        return this.Didivi;
    }
    
   public void setDidivi (java.lang.Character Didivi) {
        this.Didivi = Didivi;
    }
    /**
     */
   public java.lang.Character getDinom () {
        return this.Dinom;
    }
    
   public void setDinom (java.lang.Character Dinom) {
        this.Dinom = Dinom;
    }

etc...

and here'es the hbm.xml:

Code:

<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC 
   "-//Hibernate/Hibernate Mapping DTD 3.0//EN"
   "http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">

<hibernate-mapping>
<!-- 
   Auto-generated mapping file from
   the hibernate.org cfg2hbm engine
-->
<class 
    name="Gndivi00"
    table="gndivi00"
    catalog=""
>
   <id 
        name="Didivi"
        type="java.lang.Character"
    >
       <column name="DIDIVI" length="6" not-null="true" sql-type="char" />
       <generator class="assigned" />
    </id>
   
    <property
        name="Dinom"
        type="java.lang.Character"
    >
        <column name="DINOM" length="40" not-null="true" sql-type="char" />
   </property>

    <property
        name="Diusar"
        type="java.lang.Character"
    >
        <column name="DIUSAR" length="10" not-null="true" sql-type="char" />
   </property>

    <property
        name="Direst"
        type="java.lang.Character"
    >
        <column name="DIREST" length="1" not-null="true" sql-type="char" />
   </property>

    <property
        name="Didatc"
        type="java.math.BigDecimal"
    >
        <column name="DIDATC" length="8" not-null="true" sql-type="decimal" />
   </property>

    <property
        name="Dihrsc"
        type="java.math.BigDecimal"
    >
        <column name="DIHRSC" length="4" not-null="true" sql-type="decimal" />
   </property>

    <property
        name="Diusac"
        type="java.lang.Character"
    >
        <column name="DIUSAC" length="10" not-null="true" sql-type="char" />
   </property>

    <property
        name="Didatm"
        type="java.math.BigDecimal"
    >
        <column name="DIDATM" length="8" not-null="true" sql-type="decimal" />
   </property>

    <property
        name="Dihrsm"
        type="java.math.BigDecimal"
    >
        <column name="DIHRSM" length="4" not-null="true" sql-type="decimal" />
   </property>

    <property
        name="Diusam"
        type="java.lang.Character"
    >
        <column name="DIUSAM" length="10" not-null="true" sql-type="char" />
   </property>

</class>
</hibernate-mapping>

Sorry if I didn't test it; but at first glance, when a method return a "java.lang.Character" it only return 1 character, not 8 or 40...
Any idea? Is it supposed to works ?

Thanks

Etienne
Montreal.

etienne · **Posted:** Tue Apr 12, 2005 2:50 pm

Sorry for the title.

max · **Posted:** Tue Apr 12, 2005 4:02 pm

seems we need to get started on the "test all weird combinations of type constructs that is possible on dbs and which are not consistent with spec" unit test ,)

if you could provide a simple test case and put it in jira it would be great.

thank you

etienne · **Posted:** Tue Apr 12, 2005 5:01 pm

Sure, if I know how...

I could provide a TestCase, but I dont see how you could/should test it. Do you need to previously import a kind of DDL (create a DB? a db mock object?) and then do the "Artifact Generation", and then do the test case on the generated pojo?

I think I found Another "bug". The MySQL type binary(1) is translate to a java.lang.Object (in the hbm.xml and in the java Pojo class). I think it should be a Boolean or a bool (if Hibernate allows primitive type, I dont remerber now).

The mapping with java.lang.Object doesn't works when I am doing the "connection Factory" in the Hibernate Console. Some problem with the column... So, I change the field in the pojo for a Boolean and I remove the "type=java.lang.Object" in the hbm.xml to allow the Hibernate reflection. And then it works well.

Etienne
Montreal

max · **Posted:** Wed Apr 13, 2005 1:40 am

create the DDL that has the "bad" types. attach it

create a hbm.xml via the rev.eng. attach it

adjust the hbm.xml to have the expected types. attach it.

write down the db and driver version you used. attach that text.

voila - you've done what i've needed ,)

-max