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Error in .jcall("RJavaTools", "Ljava/lang/Object;", "invokeMethod", cl, :

While executing the following command got this error:

> dat <- colindex="colIndex," endrow="23," file="NGAP.xlsx" header="TRUE)</b" read.xlsx="" sheetindex="1," startrow="18,">

Error in .jcall("RJavaTools", "Ljava/lang/Object;", "invokeMethod", cl,  :
  java.util.zip.ZipException: invalid code -- missing end-of-block

Got this problem with a file downloaded from the internet using R command line, for an online course. Actually found that apparently the download mode needs to be set properly as write-binary (wb) since xlsx is basically a binary file (zip).

In that case we have to download again

> download.file (url=URL3, destfile="NGAP.xlsx", mode='wb')

 > dat <- colindex="colIndex," endrow="23," file="NGAP.xlsx" header="TRUE)</b" read.xlsx="" sheetindex="1," startrow="18,">

It worked fine. 
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