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Posted to users@myfaces.apache.org by "Howard W. Smith, Jr." <sm...@gmail.com> on 2013/04/13 13:40:37 UTC

@Singleton @Lock(READ) to resolve, Could not instantiate converter ...

In an effort to remove 'static' declarations throughout my app (to help
JVM's GC), I removed 'static' from the definition of the Converter class
below. So that resulted in the infamous error below:

Apr 13, 2013 4:10:38 AM org.apache.myfaces.application.ApplicationImpl
internalCreateConverter
SEVERE: Could not instantiate converter
jsf.CustomerController$CustomerControllerConverter
java.lang.InstantiationException:
jsf.CustomerController$CustomerControllerConverter
at java.lang.Class.newInstance0(Unknown Source)
at java.lang.Class.newInstance(Unknown Source)
at
org.apache.myfaces.application.ApplicationImpl.internalCreateConverter(ApplicationImpl.java:1626)
at
org.apache.myfaces.application.ApplicationImpl.createConverter(ApplicationImpl.java:1545)
at
javax.faces.application.ApplicationWrapper.createConverter(ApplicationWrapper.java:158)

I assume 'static' is necessary, because only one copy of the class is
created per application. Correct? So, can I define the class as a
@Singleton @Lock(READ) to resolve the issue?

Per NetBeans generated JSF controller/bean code, the Converter is usually
defined in the same .java file as the controller or @ManagedBean. Honestly,
I do 'not' want to use addConverter() or converterId="..." in the xhtml. I
prefer to use @FacesConverter, since this has been working for me
throughout the app.


    package jsf;

    import jpa.entities.Customer;
    import jpa.session.CustomerFacade;

    import java.io.Serializable;
    import javax.ejb.EJB;
    import javax.faces.bean.ManagedBean;
    import javax.faces.bean.RequestScoped;
    import javax.faces.component.UIComponent;
    import javax.faces.context.FacesContext;
    import javax.faces.convert.Converter;
    import javax.faces.convert.FacesConverter;

    @ManagedBean(name = "customerController")
    @RequestScoped
    public class CustomerController implements Serializable {

        @EJB
        private jpa.session.CustomerFacade ejbFacade;

        public CustomerController() {
        }

        @FacesConverter(forClass = Customer.class)
        public class CustomerControllerConverter implements Converter {

            public Object getAsObject(FacesContext facesContext,
UIComponent component, String value) {
                if (value == null || value.length() == 0) {
                    return null;
                }
                /*
                 * 2012-07-10 when user enters invalid/incomplete value
(e.g. "irene", see below) in AutoComplete
                 *
                WARNING: For input string: "irene"
                java.lang.NumberFormatException: For input string: "irene"
                        at
java.lang.NumberFormatException.forInputString(NumberFormatException.java:65)
                        at java.lang.Integer.parseInt(Integer.java:492)
                        at java.lang.Integer.valueOf(Integer.java:582)
                        at
jsf.pointOfContact.pf_PointOfContactController$PointOfContactControllerConverter.getKey(pf_PointOfContactController.java:1625)
                        at
jsf.pointOfContact.pf_PointOfContactController$PointOfContactControllerConverter.getAsObject(pf_PointOfContactController.java:1620)
                        at
org.primefaces.component.autocomplete.AutoCompleteRenderer.getConvertedValue(AutoCompleteRenderer.java:529)
                        at
javax.faces.component.UIInput.getConvertedValue(UIInput.java:1030)
                        at
javax.faces.component.UIInput.validate(UIInput.java:960)
                 *
                 */
                try {
                    Integer test = getKey(value);
                } catch (java.lang.NumberFormatException e) {
                    return null;
                }
                CustomerController controller = (CustomerController)
facesContext.getApplication().getELResolver().
                        getValue(facesContext.getELContext(), null,
"customerController");
                return controller.ejbFacade.find(getKey(value));
            }

            java.lang.Integer getKey(String value) {
                java.lang.Integer key;
                key = Integer.valueOf(value);
                return key;
            }

            String getStringKey(java.lang.Integer value) {
                StringBuffer sb = new StringBuffer();
                sb.append(value);
                return sb.toString();
            }

            public String getAsString(FacesContext facesContext,
UIComponent component, Object object) {
                if (object == null) {
                    return null;
                }
                if (object instanceof Customer) {
                    Customer o = (Customer) object;
                    return getStringKey(o.getCustomerId());
                } else {
                    throw new IllegalArgumentException("object " + object +
" is of type " + object.getClass().getName() + "; expected type: " +
Customer.class.getName());
                }
            }
        }
    }


Thanks,
Howard