[Jmol-users] JavaScript/Java/JSON/Jmol -- amazing!

[Bob H. <ha...@st...>]

JavaScript/Java/JSON/Jmol

Funny how those all begin with J.... :)

It appears I've underestimated the capabilities of JavaScript.
It turns out JSON is irrelevant in this case. Rack it up
to learning, I guess. I never would have imagined that the following 
command would work from a browser:

var atomSet = document.getElementById("jmolAppletX")
                   .getProperty("atomInfo","atomno<5")

alert(atomSet.get(0).get("info")))

The first of those, .getElementById, is JavaScript. the rest are java 
methods. It appears that getProperty is returning an object to 
JavaScript essentially just like it would to any other java component. 
AND, what's more, the object returned, "atomSet" in this case really 
is still a Java object. Heck, it's just a pointer -- there's no 
conversion!!! The class returned is Java "Object" or JavaScript 
"object", which in this case operates as a Vector, for which .get(0) 
gets the first member. That Vector entry is a Hashtable, for which 
get("info") gets the value.

return:

"[THR]1.N #1"

Useful, eh? Similarly:

document.getElementById('jmolAppletX')
    .getProperty('orientationInfo').get('moveTo')

returns "moveto 1 -400 345 332 34 0"

The common "J", of course, is for "Java". I decided just for fun to 
see what the methods of that getProperty() return object were -- and 
to my astonishment discovered all the methods of a Vector.

So, what the heck, the JSON idea allows conversion to actual 
JavaScript objects, but even without JSON, all the properties of the 
actual Java classes returned by getProperty() can be investigated. You 
just have to treat them as Java objects and use java methods.

We'll have to see if this is a generally robust finding.

This sure blurs the distinction between JavaScript and Java....

Bob Hanson

-- 

Robert M. Hanson, ha...@st..., 507-646-3107
Professor of Chemistry, St. Olaf College
1520 St. Olaf Ave., Northfield, MN 55057
mailto:ha...@st...
http://www.stolaf.edu/people/hansonr

"Imagination is more important than knowledge."  - Albert Einstein