I've been experimenting with Jelly Swing recently after finding Groovy
Swing problematic, trying to see whether it will make GUI prototyping
faster. I may have missed it, but I couldn't find a tag in any of the
tag libraries to access a static class field. There's invokeStatic
for invoking static methods. For the project I'm working on, I
wrote a GetStaticTag that works like this:
<v:getStatic var="closeOperation" className="javax.swing.JFrame"
field="EXIT_ON_CLOSE"/>
That allowed me to then do:
<frame title="Tree Frame" var="frame" size="400,400"
defaultCloseOperation="${closeOperation}">
...
</frame>
I think it's pretty important to be able to access static fields
and that a getStatic (or some other name) tag would be useful to have
in the core tag library. If I convert my GetStaticTag class code to
the style convention used in the Jelly source and add a Jelly test
for it, is it all right for me to add it to the source tree? I've
appended the simple class at the end of this message. I guess the
question is a two-parter:
1. Does the Jelly core tag library need a getStatic tag to complement
getStatic?
[ ] +1 Yes, it's generally useful.
[ ] -1 No, it's easy for someone who needs it to make their own tag.
2. May I commit code for the tag to the repository assuming I convert
it to the proper style and provide a Jelly test?
[ ] +1 Go right ahead, we can tweak the code after it's committed.
[ ] -1 No, we need to agree on what to call the tag, you should
try more than one class loader in doTag, some other reason ...
daniel
package org.savarese.vserv.jelly;
import org.apache.commons.jelly.*;
public class GetStaticTag extends TagSupport {
private String __var;
private String __field;
private String __className;
public void setVar(String var) {
__var = var;
}
public void setField(String field) {
__field = field;
}
public void setClassName(String className) {
__className = className;
}
public void doTag(XMLOutput output) throws JellyTagException {
String message = null;
if(__var == null)
message = "var";
else if(__field == null)
message = "field";
else if(__className == null)
message = "className";
if(message != null)
throw new MissingAttributeException(message);
try {
Class type = getClass().getClassLoader().loadClass(__className);
Object result = type.getField(__field).get(null);
JellyContext context = getContext();
context.setVariable(__var, result);
} catch(Throwable t) {
throw new JellyTagException("Could not access " + __className + "." +
__var + ". Original exception message: " +
t.getMessage(), t);
}
}
}
---------------------------------------------------------------------
To unsubscribe, e-mail: [EMAIL PROTECTED]
For additional commands, e-mail: [EMAIL PROTECTED]
