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What is a PoliglotMap in GraalVM?

I am working with the org.graalvm.polyglot script engine in my Java11 project to evaluate a JavaScript.
The script to be evaluated returns a JavaScript array with two entries.
...
var result={};
result.isValid=false;
result.errorMessage = new Array();
result.errorMessage[0]='Somehing go wrong!';
result.errorMessage[1]='Somehingelse go wrong!';
....
In my java code I try to evaluate the result object:
Value resultValue = context.getBindings(languageId).getMember("result");
In my Eclipse Debugger I can see that I receive a PolyglotMap containing the expected values:
I can iterate over that map to get the values with a code like this:
...
try {
mapResult = resultValue.as(Map.class);
} catch (ClassCastException | IllegalStateException | PolyglotException e) {
logger.warning("Unable to convert result object");
return null;
}
Iterator it = mapResult.entrySet().iterator();
while (it.hasNext()) {
Map.Entry pair = (Map.Entry) it.next();
String itemName = pair.getKey().toString();
Object itemObject = pair.getValue();
...
In this way I am able to extract the boolean 'isValid'. But with the object 'errorMessage' I struggle.
Inspecting the Object again within the Eclipse Debugger it looks like this:
If I test this object it is an instanceOf Map. But I am unable to get any of the values out of this object.
Can anybody help me to understand what exactly this object represents and how I can extract the both values 'Someting go wrong!' and 'Sometingelse go wrong!' ?
When I iterate over this second map it seems to be empty - even if the debugger shows me the correct values.

I'm not 100% sure why as(Map.class) behaves that way, it might be worth creating an issue on github to figure it out: github.com/oracle/graal
But if you access the values using the API without converting to a Map it would work as you expect:
var errorMessage = resultValue.getMember("errorMessage");
errorMessage.hasArrayElements(); // true
var _0th = errorMessage.getArrayElement(0);
var _1th = errorMessage.getArrayElement(1);
You can also convert the polyglotMap to Value and then do it:
val errorMessage = context.asValue(itemObject);
errorMessage.hasArrayElements(); // true
errorMessage.getArrayElement(0);
PolyglotMap of course has the get method. And the Value javadoc says that:
Map.class is supported if the value has Value.hasHashEntries() hash entries}, members or array elements. The returned map can be safely cast to Map. For value with members the key type is String. For value with array elements the key type is Long.
Can you try getting them with the Long keys?
There might be something obvious I'm missing, so in any case it's better to raise an issue on GitHub.

How to iterate and print the properties of a java form object in java script?

I have a map of type
Map<String,UserForm>
where
Class UserForm {
String userName;
String password;
//setters ;
//getters;
}
Map<String,UserForm> userMap=new HashMap<String,UserForm>();
I am adding userMap to a json object and sending the object to a JSP page in an ajax call. In javascript, I need to iterate through the userMap and print its properties (userName and password).
This is what I have done so far
for(var i in ajaxResponseData.userMap)
{
if (ajaxResponseData.userMap.hasOwnProperty(i)) {
alert(' Value is: ' + ajaxResponseData.userMap[i].userName);
}
But the above way is showing undefined in the alert box. Please help..

I would suggest double-checking that the response data is coming back in the format you're expecting and then trying to access it. Also, I believe there's no need to check if it has property i, as you are already iterating over it (thus it has been found).. Try the following snippet of code:
console.log(ajaxResponseData.userMap); // to see how your data actually looks like
for (var i in ajaxResponseData.userMap) {
// use the key to access the element
console.log(ajaxResponseData.userMap[i]); // is this the value you're looking for?
}
I have also setup a small example in JsFiddle, that alerts the values: https://jsfiddle.net/kd7u4zLt/

Trying to get the"name" of a javascript object supplied by an API

I am calling an API which is giving me back, among other things, an array of javascript objects. The objects in the array are named and I need to use the name in the new individual objects I am creating from the array. Problem is, I don't know how to get to the object's name.
{
"OldCrowMine.E9001":{"last_share":1524883404,"score":"0.0","alive":false,"shares":0,"hashrate":0},
"OldCrowMine.S9001":{"last_share":1524,"score":"648.24","alive":true,"shares":632,"hashrate":14317274},
}
I am after the "OldCrowMine.E9001" bit. I am sure this is quite simple, I just don't know how to search for the answer because I am not sure what to call this. I have tried searching for a solution.

Just loop - or am I missing something? Simplified raw data version.
var raw = {
"OldCrowMine.E9001":{"share":1524883404},
"OldCrowMine.S9001":{"share":1524}
};
for(var first in raw) {
console.log(first +" share -> "+ raw[first]["share"]);
}

var obj = {
"OldCrowMine.E9001":{"last_share":1524883404,"score":"0.0","alive":false,"shares":0,"hashrate":0},
"OldCrowMine.S9001":{"last_share":1524,"score":"648.24","alive":true,"shares":632,"hashrate":14317274},
}
console.log(Object.keys(obj)[0]);

Get the keys and map the name and the object:
var x= {
"OldCrowMine.E9001":{"last_share":1524883404,"score":"0.0","alive":false,"shares":0,"hashrate":0},
"OldCrowMine.S9001":{"last_share":1524,"score":"648.24","alive":true,"shares":632,"hashrate":14317274},
};
var mapped = Object.keys(x).map(function(d,i){return [d,x[d]]});
The name is map[n][0] and its object is map[n][1] where n is your item number.

putting json into javascript variable

I want to put a JSON object into a javascript variable as a sting in order to create a graph.
qm.createGraphData = function() {
$.post("ajax_getGraphDataWebsite ", function(json) {
qm.negativesData = json;
},"json");
qm.data = [{
"xScale":"ordinal",
"comp":[],
"main":[{
"className":".main.l1",
qm.negativesData},{
"className":".main.l2",
qm.negativesData}],
"type":"line-dotted",
"yScale":"linear"}];
}
the string value should be added to the "data" section. Now the object get's added but I need to add the string value to the variable like the sample below:
{"data":[{"x":"3283581","y":"2013-10-16"},{"x":"1512116","y":"2013-10-17"},{"x":"3967","y":"2013-10-18"},{"x":"1094","y":"2013-10-19"},{"x":"853","y":"2013-10-20"},{"x":"1205","y":"2013-10-21"},{"x":"2618700","y":"2013-10-22"},{"x":"3928291","y":"2013-10-23"},{"x":"3670318","y":"2013-10-24"},{"x":"3347369","y":"2013-10-25"},{"x":"2525573","y":"2013-10-26"},{"x":"3224612","y":"2013-10-27"},{"x":"3992964","y":"2013-10-28"},{"x":"3949904","y":"2013-10-29"},{"x":"3568618","y":"2013-10-30"},{"x":"3104696","y":"2013-10-31"},{"x":"3246932","y":"2013-11-01"},{"x":"2817758","y":"2013-11-02"},{"x":"3198856","y":"2013-11-03"},{"x":"3952957","y":"2013-11-04"},{"x":"3934173","y":"2013-11-05"},{"x":"3878718","y":"2013-11-06"},{"x":"3642822","y":"2013-11-07"},{"x":"3186096","y":"2013-11-08"}]}
This would generate the right graph for me. Does anyone know how to convert the json object into a string like above and to send it to the qm.negativesData variable?
// UPDATE
Now I've got the string with the qm.negativesData = JSON.stringify(json); solution
But my qm.negativesdata won't get added to the qm.data variable... i'm getting a console error SyntaxError: invalid property id
I suppose i'm not adding them the right way?

To convert a JSON object into a JSON string, you can try myObject.stringify(), JSON.stringify(myObject), or if you are using a library using the built in function of that library.
So, you could do something like: qm.negativesData = myObject.stringify()
Cheers

Convert some data into json format but not sure if its working

I'm trying to get the attributes of a div and trying to put it in a json format.
For example if I have a div and its attributes are:
api="something" data-page="5" data-tag="blah"
So I'm trying to put it in this format in json:
{"api":"getArticles","parameters":{"param1":"value 1","param2":value2... }}
Here's the code I've written so far, but I'm not sure if I'm doing it right because its return [object Object]. How do I check if what I'm doing is correct and see the json array in the above mentioned form?
JSfiddle link: http://jsfiddle.net/ithril/mCNbW/4/
var arr = $("div").get(0).attributes, attributes = [];
var l;
var attrinames;
var attrivalues;
var api;
for(var i = 0; i < arr.length; i++) {
if(arr[i].name.indexOf("data-")==0){
l=arr[i].name.lastIndexOf("data-",0)+"data-".length;
attrinames=arr[i].name.substr(l);
if(attrinames!="apicall"){
attrivalues=arr[i].value;
attributes.push({attrinames:attrivalues});
}
else
api=attrivalues;
}
}
var json=[]
json.push({"api":api,"parameters":attributes});
alert(json);
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.7.2/jquery.min.js"></script>
<div class="divload" data-apicall="anything.php" link="" data-page="5" data-tag="stuff">

JSON.stringify(data) will serialize the data contained within the Object.
See updated jsFiddle.

Don't use alert(variable). Use console.log(variable) and use a debugger instead. Hit F12 and view the console tab to see the results of console.log(). Also, I'd avoid naming a variable json because there is a global object named JSON.

Build the JS object whatever you want, then pass it to a JSON stringtifier, like this one:
https://github.com/douglascrockford/JSON-js
Don't try to build yourself a stringfier, because you will make mistakes, is best to use libraries or something builting.
JSON format is text, and you are building a object, you need to serialize that object to text using the json format.
Normally it will look like that:
JSON.stringify(data)