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Posted to users@myfaces.apache.org by Kostas Karadamoglou <ka...@yahoo.gr> on 2005/03/18 15:17:16 UTC
Problem with the getAsObject of a Converter
Hi again!!!
I have another problem now, Very strange Can you suggest me a solution?
I created a converter for objects of type Category in order to display
some Category beans in a selectOneMenu tag.
I have debuged the application and I noticed a strange behaviour of JSF
which I cannot understand.
Below I have the sequence explanation of the problem and the content of
each method and jsp fragment.
1)The getAsString method works perfectly and returns the following
strings "0","1","2","3","4","5","6","7"
2)The page is displayed properly, and I choose from the drop down menu a
category.
2)Afterwords JSF invokes getAsObject (I think for the chosen option)
with the str parameter null !!!!!!!
In this situation I return a null object (which is wrong).
4)After that when the page is redisplayed the getAsString throw an
Exception because of the null value
JSP-------------------------------------------------------
<h:selectOneMenu id="selectCategory"
converter="#{categoryConverter}" value="#{eventHandler.selectedCategory}">
<f:selectItems id="allCategories"
value="#{eventHandler.allCategories}"/>
</h:selectOneMenu>
getAsString------------------------------------------------
public String getAsString(FacesContext facesContext, UIComponent
uIComponent, Object obj) throws ConverterException {
String retValue=null;
if(obj==null)
throw new ConverterException("not null object of type
Category expected");
else if(obj instanceof Category){
Category category=(Category)obj;
map.put(new Integer(category.getId()), category);
retValue=String.valueOf(category.getId());
}else{
throw new ConverterException("object of type Category
expected received: "+obj.getClass().getName()+"="+obj.toString());
}
return retValue;
}
getAsObject------------------------------------------------
public Object getAsObject(FacesContext facesContext, UIComponent
uIComponent, String str) throws ConverterException {
Category retValue=null;
if(str!=null){
try{
System.out.println(str);
Integer id=Integer.valueOf(str);
retValue=(Category)map.get(id);
}catch(Exception ex){
throw new ConverterException("a number formatted string
expected");
}
}else{
//throw new ConverterException("a not null string expected");
return null;
}
return retValue;
}
Re: Problem with the getAsObject of a Converter
Posted by Heath Borders <he...@gmail.com>.
It seems like everything is declared properly. Nothing is jumping
right out at me.
On Fri, 18 Mar 2005 15:52:57 +0000, Kostas Karadamoglou
<ka...@yahoo.gr> wrote:
> Hi Heath,
> this is the decleration of the managed bean and the converter in the
> faces-config.xml
>
> <managed-bean>
> <managed-bean-name>categoryConverter</managed-bean-name>
>
> <managed-bean-class>essex.cc403.jsf.CategoryConverter</managed-bean-class>
> <managed-bean-scope>session</managed-bean-scope>
> </managed-bean>
> <converter>
>
> <converter-for-class>essex.cc403.hbeans.Category</converter-for-class>
> <converter-class>essex.cc403.jsf.CategoryConverter</converter-class>
> </converter>
>
>
> Heath Borders wrote:
>
> >Is your category converter a session bean?
> >
> >
> >On Fri, 18 Mar 2005 14:17:16 +0000, Kostas Karadamoglou
> ><ka...@yahoo.gr> wrote:
> >
> >
> >>Hi again!!!
> >>
> >>I have another problem now, Very strange Can you suggest me a solution?
> >>
> >>I created a converter for objects of type Category in order to display
> >>some Category beans in a selectOneMenu tag.
> >>
> >>I have debuged the application and I noticed a strange behaviour of JSF
> >>which I cannot understand.
> >>Below I have the sequence explanation of the problem and the content of
> >>each method and jsp fragment.
> >>
> >>1)The getAsString method works perfectly and returns the following
> >>strings "0","1","2","3","4","5","6","7"
> >>
> >>2)The page is displayed properly, and I choose from the drop down menu a
> >>category.
> >>
> >>2)Afterwords JSF invokes getAsObject (I think for the chosen option)
> >>with the str parameter null !!!!!!!
> >>In this situation I return a null object (which is wrong).
> >>
> >>4)After that when the page is redisplayed the getAsString throw an
> >>Exception because of the null value
> >>
> >>JSP-------------------------------------------------------
> >> <h:selectOneMenu id="selectCategory"
> >>converter="#{categoryConverter}" value="#{eventHandler.selectedCategory}">
> >> <f:selectItems id="allCategories"
> >>value="#{eventHandler.allCategories}"/>
> >> </h:selectOneMenu>
> >>
> >>getAsString------------------------------------------------
> >>
> >> public String getAsString(FacesContext facesContext, UIComponent
> >>uIComponent, Object obj) throws ConverterException {
> >> String retValue=null;
> >> if(obj==null)
> >> throw new ConverterException("not null object of type
> >>Category expected");
> >> else if(obj instanceof Category){
> >> Category category=(Category)obj;
> >> map.put(new Integer(category.getId()), category);
> >> retValue=String.valueOf(category.getId());
> >> }else{
> >> throw new ConverterException("object of type Category
> >>expected received: "+obj.getClass().getName()+"="+obj.toString());
> >> }
> >> return retValue;
> >> }
> >>
> >>getAsObject------------------------------------------------
> >>
> >> public Object getAsObject(FacesContext facesContext, UIComponent
> >>uIComponent, String str) throws ConverterException {
> >> Category retValue=null;
> >> if(str!=null){
> >> try{
> >> System.out.println(str);
> >> Integer id=Integer.valueOf(str);
> >> retValue=(Category)map.get(id);
> >> }catch(Exception ex){
> >> throw new ConverterException("a number formatted string
> >>expected");
> >> }
> >>
> >> }else{
> >> //throw new ConverterException("a not null string expected");
> >> return null;
> >> }
> >> return retValue;
> >> }
> >>
> >>
> >>
> >
> >
> >
> >
>
>
--
-Heath Borders-Wing
hborders@mail.win.org
Re: Problem with the getAsObject of a Converter
Posted by Kostas Karadamoglou <ka...@yahoo.gr>.
Hi Heath,
this is the decleration of the managed bean and the converter in the
faces-config.xml
<managed-bean>
<managed-bean-name>categoryConverter</managed-bean-name>
<managed-bean-class>essex.cc403.jsf.CategoryConverter</managed-bean-class>
<managed-bean-scope>session</managed-bean-scope>
</managed-bean>
<converter>
<converter-for-class>essex.cc403.hbeans.Category</converter-for-class>
<converter-class>essex.cc403.jsf.CategoryConverter</converter-class>
</converter>
Heath Borders wrote:
>Is your category converter a session bean?
>
>
>On Fri, 18 Mar 2005 14:17:16 +0000, Kostas Karadamoglou
><ka...@yahoo.gr> wrote:
>
>
>>Hi again!!!
>>
>>I have another problem now, Very strange Can you suggest me a solution?
>>
>>I created a converter for objects of type Category in order to display
>>some Category beans in a selectOneMenu tag.
>>
>>I have debuged the application and I noticed a strange behaviour of JSF
>>which I cannot understand.
>>Below I have the sequence explanation of the problem and the content of
>>each method and jsp fragment.
>>
>>1)The getAsString method works perfectly and returns the following
>>strings "0","1","2","3","4","5","6","7"
>>
>>2)The page is displayed properly, and I choose from the drop down menu a
>>category.
>>
>>2)Afterwords JSF invokes getAsObject (I think for the chosen option)
>>with the str parameter null !!!!!!!
>>In this situation I return a null object (which is wrong).
>>
>>4)After that when the page is redisplayed the getAsString throw an
>>Exception because of the null value
>>
>>JSP-------------------------------------------------------
>> <h:selectOneMenu id="selectCategory"
>>converter="#{categoryConverter}" value="#{eventHandler.selectedCategory}">
>> <f:selectItems id="allCategories"
>>value="#{eventHandler.allCategories}"/>
>> </h:selectOneMenu>
>>
>>getAsString------------------------------------------------
>>
>> public String getAsString(FacesContext facesContext, UIComponent
>>uIComponent, Object obj) throws ConverterException {
>> String retValue=null;
>> if(obj==null)
>> throw new ConverterException("not null object of type
>>Category expected");
>> else if(obj instanceof Category){
>> Category category=(Category)obj;
>> map.put(new Integer(category.getId()), category);
>> retValue=String.valueOf(category.getId());
>> }else{
>> throw new ConverterException("object of type Category
>>expected received: "+obj.getClass().getName()+"="+obj.toString());
>> }
>> return retValue;
>> }
>>
>>getAsObject------------------------------------------------
>>
>> public Object getAsObject(FacesContext facesContext, UIComponent
>>uIComponent, String str) throws ConverterException {
>> Category retValue=null;
>> if(str!=null){
>> try{
>> System.out.println(str);
>> Integer id=Integer.valueOf(str);
>> retValue=(Category)map.get(id);
>> }catch(Exception ex){
>> throw new ConverterException("a number formatted string
>>expected");
>> }
>>
>> }else{
>> //throw new ConverterException("a not null string expected");
>> return null;
>> }
>> return retValue;
>> }
>>
>>
>>
>
>
>
>
Re: Problem with the getAsObject of a Converter
Posted by Heath Borders <he...@gmail.com>.
Is your category converter a session bean?
On Fri, 18 Mar 2005 14:17:16 +0000, Kostas Karadamoglou
<ka...@yahoo.gr> wrote:
> Hi again!!!
>
> I have another problem now, Very strange Can you suggest me a solution?
>
> I created a converter for objects of type Category in order to display
> some Category beans in a selectOneMenu tag.
>
> I have debuged the application and I noticed a strange behaviour of JSF
> which I cannot understand.
> Below I have the sequence explanation of the problem and the content of
> each method and jsp fragment.
>
> 1)The getAsString method works perfectly and returns the following
> strings "0","1","2","3","4","5","6","7"
>
> 2)The page is displayed properly, and I choose from the drop down menu a
> category.
>
> 2)Afterwords JSF invokes getAsObject (I think for the chosen option)
> with the str parameter null !!!!!!!
> In this situation I return a null object (which is wrong).
>
> 4)After that when the page is redisplayed the getAsString throw an
> Exception because of the null value
>
> JSP-------------------------------------------------------
> <h:selectOneMenu id="selectCategory"
> converter="#{categoryConverter}" value="#{eventHandler.selectedCategory}">
> <f:selectItems id="allCategories"
> value="#{eventHandler.allCategories}"/>
> </h:selectOneMenu>
>
> getAsString------------------------------------------------
>
> public String getAsString(FacesContext facesContext, UIComponent
> uIComponent, Object obj) throws ConverterException {
> String retValue=null;
> if(obj==null)
> throw new ConverterException("not null object of type
> Category expected");
> else if(obj instanceof Category){
> Category category=(Category)obj;
> map.put(new Integer(category.getId()), category);
> retValue=String.valueOf(category.getId());
> }else{
> throw new ConverterException("object of type Category
> expected received: "+obj.getClass().getName()+"="+obj.toString());
> }
> return retValue;
> }
>
> getAsObject------------------------------------------------
>
> public Object getAsObject(FacesContext facesContext, UIComponent
> uIComponent, String str) throws ConverterException {
> Category retValue=null;
> if(str!=null){
> try{
> System.out.println(str);
> Integer id=Integer.valueOf(str);
> retValue=(Category)map.get(id);
> }catch(Exception ex){
> throw new ConverterException("a number formatted string
> expected");
> }
>
> }else{
> //throw new ConverterException("a not null string expected");
> return null;
> }
> return retValue;
> }
>
--
-Heath Borders-Wing
hborders@mail.win.org