Error in .jcall("RJavaTools", "Ljava/lang/Object;", "invokeMethod") when using extract_text()

[ercrema]

Hi,
I have a problem reading a pdf file. The document is not corrupted (e.g. pdftools::pdf_text() works fine, but I prefer tabulizer as I have some pages with double columns), and similar pdfs from the same repository does not produce the error. Thanks for developing the package!

Enrico

---

Please specify whether your issue is about:

• a possible bug
• a question about package functionality
• a suggested code or documentation change, improvement to the code, or feature request

If you are reporting (1) a bug or (2) a question about code, please supply:

• ensure that you can install and successfully load rJava
• a fully reproducible example using a publicly available dataset (or provide your data)
• if an error is occurring, include the output of traceback() run immediately after the error occurs
• the output of sessionInfo()

Put your code here:

## rJava loads successfully
# install.packages("rJava")
library("rJava")

## load package
library("tabulizer")

## code goes here
x<-extract_text("https://sitereports.nabunken.go.jp//files/attach/21/21232/15892_1_立石遺跡+大鶴A遺跡+上揚遺跡+前畑遺跡.pdf")
traceback()
## session info for your system
sessionInfo()

The full error message is:

Error in .jcall("RJavaTools", "Ljava/lang/Object;", "invokeMethod", cl,  : 
  java.lang.ClassCastException: class org.apache.pdfbox.cos.COSObject cannot be cast to class org.apache.pdfbox.cos.COSNumber (org.apache.pdfbox.cos.COSObject and org.apache.pdfbox.cos.COSNumber are in unnamed module of loader RJavaClassLoader @372f7a8d)

Traceback

6: stop(list(message = "java.lang.ClassCastException: class org.apache.pdfbox.cos.COSObject cannot be cast to class org.apache.pdfbox.cos.COSNumber (org.apache.pdfbox.cos.COSObject and org.apache.pdfbox.cos.COSNumber are in unnamed module of loader RJavaClassLoader @372f7a8d)", 
       call = .jcall("RJavaTools", "Ljava/lang/Object;", "invokeMethod", 
           cl, .jcast(if (inherits(o, "jobjRef") || inherits(o, 
               "jarrayRef")) o else cl, "java/lang/Object"), .jnew("java/lang/String", 
               method), j_p, j_pc, use.true.class = TRUE, evalString = simplify, 
           evalArray = FALSE), jobj = new("jobjRef", jobj = <pointer: 0x3bd8f90>, 
           jclass = "java/lang/ClassCastException")))
5: .jcheck(silent = FALSE)
4: .jcall("RJavaTools", "Ljava/lang/Object;", "invokeMethod", cl, 
       .jcast(if (inherits(o, "jobjRef") || inherits(o, "jarrayRef")) o else cl, 
           "java/lang/Object"), .jnew("java/lang/String", method), 
       j_p, j_pc, use.true.class = TRUE, evalString = simplify, 
       evalArray = FALSE)
3: .jrcall(x, name, ...)
2: stripper$getText(pdfDocument)
1: extract_text("https://sitereports.nabunken.go.jp//files/attach/21/21232/15892_1_立石遺跡+大鶴A遺跡+上揚遺跡+前畑遺跡.pdf")

SessionInfo:

R version 3.6.3 (2020-02-29)
Platform: x86_64-pc-linux-gnu (64-bit)
Running under: Ubuntu 18.04.4 LTS

Matrix products: default
BLAS:   /usr/lib/x86_64-linux-gnu/blas/libblas.so.3.7.1
LAPACK: /usr/lib/x86_64-linux-gnu/lapack/liblapack.so.3.7.1

Random number generation:
 RNG:     Mersenne-Twister 
 Normal:  Inversion 
 Sample:  Rounding 
 
locale:
 [1] LC_CTYPE=en_GB.UTF-8          LC_NUMERIC=C                  LC_TIME=en_GB.UTF-8          
 [4] LC_COLLATE=en_GB.UTF-8        LC_MONETARY=en_GB.UTF-8       LC_MESSAGES=en_GB.UTF-8      
 [7] LC_PAPER=en_GB.UTF-8          LC_NAME=en_GB.UTF-8           LC_ADDRESS=en_GB.UTF-8       
[10] LC_TELEPHONE=en_GB.UTF-8      LC_MEASUREMENT=en_GB.UTF-8    LC_IDENTIFICATION=en_GB.UTF-8

attached base packages:
[1] stats     graphics  grDevices utils     methods   base     

other attached packages:
[1] tabulizer_0.2.2 rJava_0.9-11   

loaded via a namespace (and not attached):
[1] tabulizerjars_1.0.1 compiler_3.6.3      tools_3.6.3         yaml_2.2.1          png_0.1-7     

[dbampoh]

Did you ever figure this issue out?