Vaadin Testbench: NullpointerException while detecting an existing ButtonEl

Flow
1

Hi,

I have a problem with my test script for 5 days now! I simply can’t find a simple button element - neither using $(ButtonElement.class).get(0), $(ButtonElement.class).first() nor using my Webdriver (ChromeDriver, newest version).

It always throws a NullpointerException. It’s curious that this detection works pretty fine before this test step. And I see the button, the scipt should be able to find it too!!! What coud be the reason, that makes a TestBenchTestCase forgetting his WebDriver and his implementation?

I’m ready to go spare and have no idea where to look for, please help me.
Thank you!

2

This is the code: (The method checks that a line in a GridElement element has disappeared after I combined it in a group. (implemented by my company) )

if (!shouldElementsBeInList) {

        for (int numberOfActualRow = 0; numberOfActualRow < getGridRowCount(); numberOfActualRow++) {

            String foundEntryName = getGridCellByIndex(numberOfActualRow, 1).getText();
            String foundEntryVersion = getGridCellByIndex(numberOfActualRow, 2).getText();

            boolean isThisEntryMatchingSearchedName = searchedEntryName.equals(foundEntryName);
            boolean isThisEntryMatchingSearchedVersion = searchedEntryVersion.equals(foundEntryVersion);

            boolean isThisSoftwareEntryInGridAnyway = isThisEntryMatchingSearchedName
                    && isThisEntryMatchingSearchedVersion;

            generalHelper.failWithThisErrorMessageIfThisConditionIsTrue(isThisSoftwareEntryInGridAnyway,
                    "Entry " + searchedEntryName + ";" + searchedEntryVersion
                            + " has been found in list but should be in a group!");


//Problem line:
boolean isThereAFurtherPage = $(ButtonElement.class).caption(nextPage).last().isEnabled();

            if (numberOfActualRow == numberOfLastRowInGrid && isThereAFurtherPage) {
                generalHelper.clickButtonByCaption(nextPage);
                numberOfLastRowInGrid = getGridRowCount() - 1;
            }
        }

}

3

At least I resolved the problem! The reason seemed to be the access to my ChromeDriver.

To avoid opening 5 browser windows I use one general driver in a helper class. In another helper class I initialized another new Chrome Driver (legacy code) that was null.

I didn’t know that this would take influence to ElementQueries like $(ButtonElement.class).all() etc.

Maybe this information will help somebody else.