sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) using findElement(By.className()) through Selenium and Java

问题

When I execute the following code:

driver.findElement(By.className("qview-product-name")).click();

I get the following error

Session ID: d5df6f837164b1738991e8dc09027fe0
*** Element info: {Using=class name, value=qview-product-name}
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
    at java.lang.reflect.Constructor.newInstance(Unknown Source)
    at org.openqa.selenium.remote.http.W3CHttpResponseCodec.createException(W3CHttpResponseCodec.java:187)
    at org.openqa.selenium.remote.http.W3CHttpResponseCodec.decode(W3CHttpResponseCodec.java:122)
    at org.openqa.selenium.remote.http.W3CHttpResponseCodec.decode(W3CHttpResponseCodec.java:49)
    at org.openqa.selenium.remote.HttpCommandExecutor.execute(HttpCommandExecutor.java:158)
    at org.openqa.selenium.remote.service.DriverCommandExecutor.execute(DriverCommandExecutor.java:83)
    at org.openqa.selenium.remote.RemoteWebDriver.execute(RemoteWebDriver.java:552)
    at org.openqa.selenium.remote.RemoteWebDriver.findElement(RemoteWebDriver.java:323)
    at org.openqa.selenium.remote.RemoteWebDriver.findElementByClassName(RemoteWebDriver.java:412)
    at org.openqa.selenium.By$ByClassName.findElement(By.java:389)
    at org.openqa.selenium.remote.RemoteWebDriver.findElement(RemoteWebDriver.java:315)
    at Logins.bcLogin(Logins.java:140)
    at Exception.main(Exception.java:54)

The webpage I am working on definately contains the following HTML code and I have tried waiting an appropriate amount of time to execute.

<dd class="qview-product-name">
    <span class="note">1 x </span>
                    <a href="Link_here"_blank">Title</a>
            </dd>

I thought I was getting pretty good at locating elements using the various methods, but this has me stumped. Any ideas on how I should go about troubleshooting? Thanks!

回答1:

There are a couple of things you need to take care of:

By.className("qview-product-name") refers to the parent <dd> tag and perhaps is not the desired element you want to click. Rather your usecase must be to click on the <a href="Link_here"_blank">Title</a> element.
As per best practices, while invoking click() you need to induce you need to induce WebDriverWait for the elementToBeClickable() and you can use either of the following Locator Strategies:

linkText:

new WebDriverWait(driver, 20).until(ExpectedConditions.elementToBeClickable(By.linkText("Title"))).click();

cssSelector:

new WebDriverWait(driver, 20).until(ExpectedConditions.elementToBeClickable(By.cssSelector("dd.qview-product-name a[href='Link_here']"))).click();

xpath:

new WebDriverWait(driver, 20).until(ExpectedConditions.elementToBeClickable(By.xpath("//dd[@class='qview-product-name']//a[@href='Link_here' and text()='Title']"))).click();

Additional Considerations

Ensure that:

JDK is upgraded to current levels JDK 8u222.
Selenium is upgraded to current levels Version 3.141.59.
ChromeDriver is updated to current ChromeDriver v77.0 level.
Chrome is updated to the current Chrome Version 77.0 level. (as per ChromeDriver v77.0 release notes)
Clean your Project Workspace through your IDE and Rebuild your project with required dependencies only.
If your base Web Client version is too old, then uninstall it and install a recent GA and released version of Web Client.
Take a System Reboot.
Execute your @Test as non-root user.

来源：https://stackoverflow.com/questions/58195202/sun-reflect-nativeconstructoraccessorimpl-newinstance0native-method-using-find

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java

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linktext