js.executeScript("return document.title") works fine as expected but I'm not sure why my code returns null pointer error. what is wrong here?
String testJs= "function test() {arr = 111; return arr;}; test();";
JavascriptExecutor js = (JavascriptExecutor) driver;
int a = (Integer) js.executeScript(testJS);
This javascript
function test() {arr = 111; return arr;};
test();
Calls the method test() but doesn't do anything with the result, ie. doesn't return it to the caller.
So
int a = (Integer) js.executeScript(testJS);
will return null and try to be dereferenced which will fail because dereferencing null throws NullPointerException.
Javadoc for JavascriptExecutor.html#executeScript(java.lang.String, java.lang.Object...)
Maybe you want the javascript
function test() {arr = 111; return arr;};
return test();
This works for me
System.setProperty("webdriver.chrome.driver", "C:\\Users\\me\\Downloads\\chromedriver.exe");
ChromeDriver driver = new ChromeDriver();
JavascriptExecutor executor = (JavascriptExecutor) driver;
String js = "function test() {" +
"arr = 111; return arr;" +
"}; return test()";
Long a = (Long) executor.executeScript(js);
System.out.println(a);
ClassCastException? Just change the type of your variable. Because it works for me.
One of Boolean, Long, String, List or WebElement. Or null. Thank you for your time. Appreciate it.Yeah, the key thing is not to forget insert the return, f.e.:
Long dateNow = (Long) jse.executeScript("return Date.now()");
js.executeScript()return? Javadoc clearly saysOne of Boolean, Long, String, List or WebElement. Or null..