Name: gm110360 Date: 05/20/2003


FULL PRODUCT VERSION :
java version "1.4.2-beta"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.4.2-beta-b19)
Java HotSpot(TM) Client VM (build 1.4.2-beta-b19, mixed mode)

FULL OS VERSION :
Microsoft Windows XP [Version 5.1.2600]

A DESCRIPTION OF THE PROBLEM :
I have written a BeanInfo class that returns at getPropertyDescriptors() one PropertyDescriptor among others that has no Read method. (This is a write-only property according to the API specification, thus allowed). But in this case, Introspector.getBeanInfo(Class beanclass) will use a GenericBeanInfo instead of MyBeanInfo.
Most probably the reason for that is the new code in Introspector.findExplicitBeanInfo (Under the comment "Make sure that the returned BeanInfo matches the class.")
   Method method = pds[j].getReadMethod();
   if (method.getDeclaringClass() ........
PropertyDescriptor.getReadMethod() may return null! (And the NullPointerException will be "silently ignored")

  To reproduce this problem, the write-only property has to be the first one returned by getPropertyDescriptors(), but also all properties can be write-only.
And the BeanInfo class has to be in a different package as the class, which is added to the Introspector's BeanInfoSearchPath.

Compare to Bug 4855594, and also to Bug xxxxxxx (the one that I submitted on 6th march, against jdk1.4.1, concerning ProeprtyDescriptors without either getmethod and setmethod)



REPRODUCIBILITY :
This bug can be reproduced always.

---------- BEGIN SOURCE ----------
package classes;

import java.beans.*;

public class Bug2
{
    public static void main(String[] args)
    {
        String[] bsp = Introspector.getBeanInfoSearchPath();
        String[] bspNew = new String[bsp.length+1];
        bspNew[0] = "beaninfos";
        for (int i=0; i<bsp.length; i++) {
            bspNew[i+1] = bsp[i];
        }
        Introspector.setBeanInfoSearchPath(bspNew);

        try
        {
            BeanInfo bi = Introspector.getBeanInfo(Bug2.class);
            PropertyDescriptor[] pd = bi.getPropertyDescriptors();
            for (int i=0; i<pd.length; i++)
            {
                String n = pd[i].getName();
                System.out.println(n);
            }
        }
        catch (Exception e)
        {
            e.printStackTrace();
            System.exit(1);
        }
        System.exit(0);
    }

    private int f=0;
    public void setF(int P_f) { f = P_f; }
    public int getF() { return f; }

    private int g=0;
    public void setG(int P_g) { g = P_g; }
    public int getG() { return g; }
}

--------------------------------------------------------------------

package beaninfos;

import classes.Bug2;
import java.beans.*;

public class Bug2BeanInfo extends SimpleBeanInfo
{
    public PropertyDescriptor[] getPropertyDescriptors()
    {
        PropertyDescriptor fDes, gDes;
        try
        {
            fDes = new PropertyDescriptor("f_from_my_BeanInfo",
                                          Bug2.class,
                                          null, //"getF" would work here
                                          "setF");
            gDes = new PropertyDescriptor("g_from_my_BeanInfo",
                                          Bug2.class,
                                          "getG",
                                          "setG");
            return new PropertyDescriptor[] {fDes, gDes};
        }
        catch (IntrospectionException e)
        {
            e.printStackTrace();
            return null;
        }
    }
}

---------- END SOURCE ----------

CUSTOMER SUBMITTED WORKAROUND :
Return a PropertyDescriptor-Array whit the write-only property not at the first position. (But what if the class has only write-only properties?)
(Review ID: 186072)
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