IllegalArgumentException from CharBooleanType sub-class

simon.brunning · **Posted:** Tue May 10, 2005 6:47 am

I'm having a bit of a problem with a custom user type. in my legacy database, one column can contain either a 'C', or a blank. I'd like to map these to true and false respectivly. This is very nearly the same as the true_false type, so I used TrueFalseType as a template:

Code:

package uk.co.trisystems.morph.user_type;

import java.sql.ResultSet;
import java.sql.SQLException;

import net.sf.hibernate.type.CharBooleanType;

public class BooleanCBlankType extends CharBooleanType {

    protected final String getTrueString() {
        return "C";
    }

    protected final String getFalseString() {
        return " ";
    }

}

My mapping document looks like so:

Code:

<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 2.0//EN" "http://hibernate.sourceforge.net/hibernate-mapping-2.0.dtd">
<hibernate-mapping>

    <class name="uk.co.trisystems.morph.currency.CurrencyDAO" table="MACPFCC0">

...
        
        <property name="cancelled" column="CCCYCF" not-null="true" type="uk.co.trisystems.morph.user_type.BooleanCBlankType">
            <meta attribute="field-description">Currency Cancelled</meta>
        </property>

...

    </class>    
</hibernate-mapping>

I used hbm2java to generate my CurrencyDAO.java file. The cancelled property is an instance of BooleanCBlankType, and eberything generates and compiles OK. When I try to pull data from by database, though, I get an exception:

Code:

ERROR 11:40:41 net.sf.hibernate.property.BasicPropertyAccessor$BasicSetter.set():60 - IllegalArgumentException in class: uk.co.trisystems.morph.currency.CurrencyDAO, setter method of property: cancelled
ERROR 11:40:41 net.sf.hibernate.property.BasicPropertyAccessor$BasicSetter.set():64 - expected type: uk.co.trisystems.morph.user_type.BooleanCBlankType, actual value: java.lang.Boolean

Exception in thread "main" net.sf.hibernate.PropertyAccessException: IllegalArgumentException occurred while calling setter of uk.co.trisystems.morph.currency.CurrencyDAO.cancelled
   at net.sf.hibernate.property.BasicPropertyAccessor$BasicSetter.set(BasicPropertyAccessor.java:68)
   at net.sf.hibernate.persister.AbstractEntityPersister.setPropertyValues(AbstractEntityPersister.java:229)
   at net.sf.hibernate.impl.SessionImpl.initializeEntity(SessionImpl.java:2224)
   at net.sf.hibernate.loader.Loader.initializeEntitiesAndCollections(Loader.java:319)
   at net.sf.hibernate.loader.Loader.doQuery(Loader.java:309)
   at net.sf.hibernate.loader.Loader.doQueryAndInitializeNonLazyCollections(Loader.java:138)
   at net.sf.hibernate.loader.Loader.doList(Loader.java:1063)
   at net.sf.hibernate.loader.Loader.list(Loader.java:1054)
   at net.sf.hibernate.hql.QueryTranslator.list(QueryTranslator.java:854)
   at net.sf.hibernate.impl.SessionImpl.find(SessionImpl.java:1554)
   at net.sf.hibernate.impl.QueryImpl.list(QueryImpl.java:49)
   at uk.co.trisystems.morph.currency.CurrencyDAOTest.allCurrencies(CurrencyDAOTest.java:23)
   at uk.co.trisystems.morph.currency.CurrencyDAOTest.main(CurrencyDAOTest.java:54)
Caused by: java.lang.IllegalArgumentException: argument type mismatch
   at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
   at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
   at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
   at java.lang.reflect.Method.invoke(Unknown Source)
   at net.sf.hibernate.property.BasicPropertyAccessor$BasicSetter.set(BasicPropertyAccessor.java:38)
   ... 12 more

I included what looks like some revevant logging info in there, too. I've searched this forum and googled about a bit, but I can't find a solution to this. So, what am I doing stupid?

I'm using Hibernate 2.8.1, running against an AS/400 (iSeries).

max · **Posted:** Tue May 10, 2005 8:07 am

your type should be a UserType not a Hibernate Type.

simon.brunning · **Posted:** Tue May 10, 2005 8:22 am

max wrote:

your type should be a UserType not a Hibernate Type.

Are you saying that I can't sub-class anything from the net.sf.hibernate.type package, but must instead write my own from scratch, impementing UserType?

simon.brunning · **Posted:** Tue May 10, 2005 8:30 am

Thanks for your time, Max.

OK, so I've written my own class. I've now got:

Code:

package uk.co.trisystems.morph.user_type;

public class BooleanCBlankType extends AbstractBooleanType {

    public final String getTrueString() {
        return "C";
    }

    public final String getFalseString() {
        return " ";
    }

}

and:

Code:

package uk.co.trisystems.morph.user_type;

import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Types;

import org.apache.log4j.Logger;

import net.sf.hibernate.Hibernate;
import net.sf.hibernate.HibernateException;
import net.sf.hibernate.UserType;

public abstract class AbstractBooleanType implements UserType {
    protected final Logger logger = Logger.getLogger(this.getClass());

    public Object deepCopy(Object value) throws HibernateException {
        return value;
    }

    public boolean equals(Object x, Object y) throws HibernateException {
        return x == null ? y == null : x.equals(y);
    }

    public abstract String getFalseString();

    public abstract String getTrueString();

    public boolean isMutable() {
        return false;
    }

    public Object nullSafeGet(ResultSet rs, String[] names, Object owner)
            throws HibernateException, SQLException {
        final Object nullSafeGet = Hibernate.CHARACTER
                .nullSafeGet(rs, names[0]);
        String databaseValue = String.valueOf(nullSafeGet);
        if (databaseValue == this.getTrueString()) {
            return Boolean.TRUE;
        } else {
            return Boolean.FALSE;
        }
    }

    public void nullSafeSet(PreparedStatement st, Object value, int index)
            throws HibernateException, SQLException {
        final boolean pojoValue = ((Boolean) value).booleanValue();
        if (pojoValue) {
            Hibernate.CHARACTER.nullSafeSet(st, this.getTrueString(), index);
        } else {
            Hibernate.CHARACTER.nullSafeSet(st, this.getFalseString(), index);
        }
    }

    public Class returnedClass() {
        return Boolean.class;
    }

    public int[] sqlTypes() {
        int[] typeList = { Types.CHAR };
        return typeList;
    }

}

I'm still getting exactly the same error messages. Clearly I didn't understand you, Max.

max · **Posted:** Tue May 10, 2005 8:32 am

what is the signature of your cancellable property ?

your returnedclass is saying it should take and return a Boolean - maybe yours are a boolean ?

simon.brunning · **Posted:** Tue May 10, 2005 8:54 am

max wrote:

what is the signature of your cancellable property ?

your returnedclass is saying it should take and return a Boolean - maybe yours are a boolean ?

I don't think I've really got the hang of these user types yet. ;-) In my CurrencyDAO.hbm.xml file, I've got a property declared as so:

Code:

<property name="cancelled" column="CCCYCF" not-null="true" type="uk.co.trisystems.morph.user_type.BooleanCBlankType">
    <meta attribute="field-description">Currency Cancelled</meta>
</property>

CurrencyDAO.java is generated for me by hbm2java. I've not touched the code by hand at all. Its cancelled property is an instance of BooleanCBlankType, not boolean or Boolean. (Is this as it should be, or have I declared the property incorrectly in my hbm.xml file?) Here it is:

Code:

    /** persistent field */
    private BooleanCBlankType cancelled;

    /** 
     * Currency Cancelled
     */
    public BooleanCBlankType getCancelled() {
        return this.cancelled;
    }

    public void setCancelled(BooleanCBlankType cancelled) {
        this.cancelled = cancelled;
    }

The BooleanCBlankType.java class that I've written returns Boolean.class from its returnedClass() method, and int[] typeList = {Types.CHAR} from its sqlTypes() method, indicating (I think) that the column on the database side is a CHAR field (and that only one column is involved), and that the java side value is a Boolean.

My nullSafeGet and nullSafeSet methods are responsible for performing the conversions. But I don't think that the problem lies with them, since they don't turn up in the traceback. Or is this an unwarrented assumption?

The problem that I can see is that in net.sf.hibernate.property.BasicPropertyAccessor$BasicSetter.set(), it's trying to call the CurrencyDAO.setCancelled() method with a Boolean, but it wants a BooleanCBlankType instead. So, either the CurrencyDAO.cancelled property ought to be a Boolean, or CurrencyDAO.setCancelled() should be passed a BooleanCBlankType. I am new to Hibernate, and I don't know which of these is the case.

I suspect that the problem lies in my CurrencyDAO.hbm.xml file somewhere, rather than in my UserType code, but I'm far from sure. ;-)

Your help is very much appreciated, Max.

max · **Posted:** Tue May 10, 2005 8:56 am

if you use hbm2java you need to have the UserType class in the classpath so hbm2java can actually load it and ask what class it should use.

/max

simon.brunning · **Posted:** Tue May 10, 2005 8:59 am

max wrote:

if you use hbm2java you need to have the UserType class in the classpath so hbm2java can actually load it and ask what class it should use.

/max

hibernate2.jar is in the classpath. Is that OK?

max · **Posted:** Tue May 10, 2005 9:04 am

your usertype is not inside hibernate2.jar is it ? ;)

/max

simon.brunning · **Posted:** Tue May 10, 2005 9:09 am

max wrote:

your usertype is not inside hibernate2.jar is it ? ;)

/max

Nope, hibernate2.jar is as shipped.

Ah, are you saying that my type has to be in the classpath when hbm2java runs? My class is in the classpath at runtime, but it won't yet have compiled when hbm2java runs.

If I were to compile my user types prior to running hbm2java, would the generated CurrencyDAO.java file have the cancelled property as a Boolean rather than as a BooleanCBlankType?

max · **Posted:** Tue May 10, 2005 9:11 am

yes - how else did you expect hbm2java to discover what return type your type has ? ;)

/max

simon.brunning · **Posted:** Tue May 10, 2005 10:32 am

Thanks, Max. After a rather unseemly wrestling match with Ant, I have my my user types before hbm2java, and the hbm2java target has the correct classpath. All is now working beautifully.

Thanks very much, Max. I appreciate the help.