Find if next sibling exist - selenium

Question

I try to write some robot test cases and I got stuck. I need to extract some links from a page. The links are stored inside an <li> tag which is also inside an <ul>. The problem is that after I extract the first link I need to go to the next <li> (the first <li> next sibling) but how can I find if there is a next sibling without getting an error or the application stop. I know, I can use Element Should Contain keyword but in case if it not contain I get an error.
I want to do something like this:
if next sibling exist do something
else go do something else
The html should look like this.
<ul id="top_menu" role="menubar" class="">
<li class="menu_accordion_section" id="cat_1">
</li>
<li class="menu_accordion_section" id="cat_2">
</li>
</ul>

Answer 1

There is direct message, you can use execute script to create a varaible.
so i created a keyword
Validate child element exists
it takes two argument parent(Webelement) and child(Xpath) to search for child inside the parent.
Validate child element exists ${parent} ./h3
Assuming parent xpath to as : //ul[#id="top_menu"] , the above code will search for equalent xpath //ul[#id="top_menu"]/./h3 note taht context is parent and not root
so this will be equalent to xpath
*** Test Cases ***
Google Search
[Tags] you probably do not have this many tags in real life
Wait Until Element Is Visible CSS=[id="introduction-container"]
${parent}= Get webelement xpath=//*[#id="introduction-container"]
${result}= Validate child element exists ${parent} ./h3
Should Be True ${result}
*** Keywords ***
Validate child element exists
[Arguments] ${parent} ${child}
${child}= Execute Javascript return window.document.evaluate( arguments[1], arguments[0], null, XPathResult.FIRST_ORDERED_NODE_TYPE, null ).singleNodeValue; ARGUMENTS ${parent} ${child}
[Return] ${child}

Answer 2

one solution is iterate over the menu, follow a code example(this code has not been tested, may need some adjustments):
List<WebElement> menuItens = getDriver().findElement(By.id("top_menu")).findElements(By.tagName("li"));
List<String> links = new ArrayList<>();
menuItens.forEach(item -> {
links.add(item.findElement(By.tagName("a")).getAttribute("href"));
});
return links;