JPanel which uses reflection to create a simple property editor

Hi everyone,
Here's what I'd like: a custom JPanel, let's call it DesiredJPanel, which can be passed an object as an argument, and which then detects all the public getters and setters on that object, and then creates a simple property editor, with default behavior for numbers, booleans, Strings, etc. It might be used like this:
JDialog dialog = new JDialog(new DesiredJPanel(someObjectWithSettersAndGetters)));
dialog.setVisible(true);
Then we'd get a dialog populated with the current values of all relevant properties. The panel could have a button bar, with an ok button. When you press it, all the properties of someObjectWithSettersAndGetters are set according to what the user has entered in the fields of the panel.
This seems like a pervasive, standard use case. It also seems like javabeans is intended for this. E.g. quoting wikipedia: "JavaBeans are reusable software components for Java that can be manipulated visually in a builder tool." Moreover, there is the java.beans.PropertyEditor interface.
And yet I can't find anything that seems to do this, so I end up writing the same boilerplate style code over and over. I found some commercial thing (this is for an open source project), and netbeans does what I'm after but it's netbeans. I want something that can be used in any swing app.
Apologies if I've overlooked something obvious or posted this to the wrong forum (if either, please let me know!).
All best and happy new year!
- Jeff

Not exactly what you asked for, but reasonably close. You can use my [Bean Table Model|http://www.camick.com/java/blog.html?name=bean-table-model] to create a JTable which will display all the properties in a single row of a table. The appropriate renderer/editor is used for each property.
Play with the commented out code in JButtonTableModel class to see what you get for your particular bean.

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How To: Use reflection to create instance of generic type?

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Is this erasure business prohibiting me from doing this? Or does the reflection API provide a way for me to specify at run time the type of the elements in the list? If so, I don't see it. Is my only recourse to simply ignore the type safety warnings?

Harald,
I appreciate all your help on this topic. I think we are close to putting this thing to rest, but I'd like to run one more thing by you.
I tried something similar to your suggestion:public static <T> List<T> loadFromStorage(Class<T> clazz) {
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I was able to get around this problem and eliminate the compiler warning, but I'm not sure I like the way I did it. All of my persistent classes extend a common base class. So, I added a static Map to my base class:class Base
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}And added a static initializer to each of my persistent classes:class Foo extends Base
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}So now my persistence code can replace Class.forName("my.package.Foo") with Base.getClass("my.package.Foo"). Since Foo.class is of type Class<Foo>, this will give me the Class<Foo> I want instead of a Class<?>.
Basically, it works and I have no compiler warnings, but it is unfortunate that I had to come up with my own mechanism to obtain a Class<Foo> object when my starting point was the string "my.package.Foo". I think that the JDK, in order to fully support reflection with generic types, should provide a standard API for doing this. I should not have to invent my own.
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interesting approach.. I wiil try that... bellow is my current code, which runs well to the first level of attributes.. When I tryied to load the deeper levels, it caused a StackOverflow... I will try the cited approach...
/** 2003 � www.atlantico.com.br */
package com.atlantico.sigweb.util;
import javax.swing.tree.DefaultMutableTreeNode;
import java.lang.reflect.Field;
import java.util.Collection;
import java.util.Iterator;
* Esta classe re�ne funcionalidades que n�o est�o vinculadas
* a um processo espec�fico.
* @author Felipe Ga�cho
* @version 15/09/2003
public abstract class Util {
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if (object instanceof Collection) {
for (
Iterator children = ((Collection) object).iterator();
children.hasNext();
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Hi Guys,
Need you help
Situation is like this �.I have a function which accept the Sting parameter
Which is actually a full name of class �.using reflection I created the class and object
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Ragnvald Barth
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Found it!
the java.lang.reflect.Array class solves it!
Yes !!!

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