NoSuchMethodException when calling sendKeys on object of class org.openqa.selenium.remote.RemoteWebElement via R package rJava - r

Question

I am trying to use the selenium webdriver API directly from R using rJava. I am subject to a fairly restrictive IT environment, so I can't access a remote driver currently (hence why I'm not currently using the Rselenium package), and I don't have either Chrome or Firefox availaible--just phantomjs. I am able to get this working okay from the Scala REPL. I used sbt to get all the dependenices--build.sbt contains, for example:
retrieveManaged := true
libraryDependencies ++= Seq (
"org.seleniumhq.selenium" % "selenium-java" % "3.9.1",
"com.codeborne" % "phantomjsdriver" % "1.4.4"
)
(Note that I have phantomjs installed as /usr/local/bin/phantomjs, and it is
version 2.1.1).
I then copied all the jar files to a single-level folder via cp jars/*/*/*.jar alljars/ containing the following:
animal-sniffer-annotations-1.14.jar httpcore-4.4.6.jar selenium-api-3.9.1.jar
byte-buddy-1.7.9.jar j2objc-annotations-1.1.jar selenium-chrome-driver-3.9.1.jar
checker-compat-qual-2.0.0.jar jline-2.14.5.jar selenium-edge-driver-3.9.1.jar
commons-codec-1.10.jar jsr305-1.3.9.jar selenium-firefox-driver-3.9.1.jar
commons-exec-1.3.jar okhttp-3.9.1.jar selenium-ie-driver-3.9.1.jar
commons-logging-1.2.jar okio-1.13.0.jar selenium-java-3.9.1.jar
error_prone_annotations-2.1.3.jar phantomjsdriver-1.4.4.jar selenium-opera-driver-3.9.1.jar
gson-2.8.2.jar scala-compiler-2.12.4.jar selenium-remote-driver-3.9.1.jar
guava-23.6-jre.jar scala-library-2.12.4.jar selenium-safari-driver-3.9.1.jar
httpclient-4.5.3.jar scala-reflect-2.12.4.jar selenium-support-3.9.1.jar
I start Scala via scala -cp "alljars/*" and can the do following:
val drv = new org.openqa.selenium.phantomjs.PhantomJSDriver
drv.get("https://www.google.com")
val q = drv.findElementByName("q")
q.sendKeys("rJava selenium")
q.submit
drv.getTitle
I think the following is roughly the same thing in R using rJava:
library(rJava)
.jinit()
jars <- dir("alljars", pattern = "*.jar", full.names = TRUE)
.jaddClassPath(jars)
drv <- .jnew('org/openqa/selenium/phantomjs/PhantomJSDriver')
drv$get("https://www.google.com")
q <- drv$findElementByName("q")
q$sendKeys("rJava selenium")
q$submit()
drv$getTitle()
This fails at the point q$sendKeys("rJava selenium") with the following error:
Error in .jcall("RJavaTools", "Ljava/lang/Object;", "invokeMethod", cl, :
java.lang.NoSuchMethodException: No suitable method for the given parameters
In RStudio, if I type q$ and press TAB, sendKeys is definitely in the list of available methods. I tried to be explicit about this, and tried:
keys <- .jnew("java/lang/String", "rJava selenium")
keys <- .jcast(keys, "java/lang/CharSequence", check = TRUE)
q <- .jcast(q, "org/openqa/selenium/WebElement", check = TRUE)
.jcall(q, "V", "sendKeys", keys)
which resulted in the following error:
Error in .jcall(q, "V", "sendKeys", keys) :
method sendKeys with signature (Ljava/lang/CharSequence;)V not found
q has class org/openqa/selenium/remote/RemoteWebElement in R, and org/openqa/selenium/WebElement in Scala; but in both cases the return is void and the required argument is CharSequence according to the javadocs. I tried a few variations of this--java.lang.String instead of CharSequence, RemoteWebElement instead of WebElement, etc., but no joy.
I doubt this is a problem with rJava, but I'm stumped nonetheless and need help!

Answer 1

Oh good grief. I didn't know about .jmethods. Running this:
> .jmethods(q, "sendKeys")
[1] "public void org.openqa.selenium.remote.RemoteWebElement.sendKeys(java.lang.CharSequence[])"
So, basically, my problem was that I was passing String instead of String[]. That is, instead of:
q$sendKeys("rJava selenium")
I can use:
q$sendKeys(.jarray("rJava selenium"))
The more you know...