Oql In Visualvm V1.4.4 - Get A Class's Field Names

I would like to execute an OQL query in VisualVM (v1.4.4) to retrieve the (non-static) field names for an object. The OQL documentation describes heap.findClass(className). This r

Solution 1:

You need to use map() function. The following OQL retrieves the field names of ByteArrayInputStream class:

selectmap(heap.findClass('java.io.ByteArrayInputStream').fields, 'it.name')

Solution 2:

Just to add to the very helpful answer from @Tomas - which I have accepted.

Based on his insight, I can also now do things like this in OQL - using a callback instead of an expression string:

map(heap.findClass('java.io.ByteArrayInputStream').fields, function (it) { 
  var res = ''; 
  res += toHtml(it.name) + " : " + toHtml(it.signature); 
  return res + "<br>"; 
});

The above example is trivial, but it opens up more possibilities.

His answer also made me realize where I was going wrong: OQL uses JavaScript expression language - not the exactly the same as JavaScript.