Check if PsiElement is a string

Question

When adding 'intentions' to PhpStorm (or other JetBrains IDE's), how can I detect whether a PsiElement is a string? I've based my code off the only intention example I could find. I can't seem to find proper documentation. This is as far as I got:

@NonNls public class SomeIntention extends PsiElementBaseIntentionAction implements IntentionAction {

    public boolean isAvailable(@NotNull Project project, Editor editor, @Nullable PsiElement element) {
        if (element == null || !(element instanceof /* String? */) {
            return false;
        }
    }

}

instanceof String obviously doesn't work, but even using PsiViewer I can't figure out how to test whether it's a string.

Answer 1

The following worked to check if our current node is a string (either double quoted or single quoted):

ASTNode ast_node = element.getNode();

if(ast_node == null) {
    return false;
}

IElementType element_type = ast_node.getElementType();

if(element_type != PhpTokenTypes.STRING_LITERAL
&& element_type != PhpTokenTypes.STRING_LITERAL_SINGLE_QUOTE) {
    return false;
}

return true;

In my case, I only wanted 'raw strings', not strings with variables or concatenation. If any variables or concatenation signs exist in a string, PSI sees those as separate siblings. So I could find raw strings by ruling out strings with siblings:

// Disregards strings with variables, concatenation, etc.
if (element.getPrevSibling() != null || element.getNextSibling() != null) {
    return false;
}

return true;