R/output.R

In leeper/tabulizer: Extract Tables from PDF Documents

write_csvs <- function(tables, file, outdir, ...) {
  file <- basename(file)
  writer <- new(J("technology.tabula.writers.CSVWriter"))
  tablesIterator <- tables$iterator()
  p <- 1L
  while (.jcall(tablesIterator, "Z", "hasNext")) {
    filename <- paste0(tools::file_path_sans_ext(file), "-", p, ".csv")
    outfile <- normalizePath(file.path(outdir, filename), mustWork = FALSE)
    bufferedWriter <- new(
      J("java.io.BufferedWriter"),
      new(J("java.io.FileWriter"), outfile)
    )
    tab <- .jcall(tablesIterator, "Ljava/lang/Object;", "next")
    writer$write(bufferedWriter, tab)
    rm(tab)
    bufferedWriter$close()
    p <- p + 1L
  }
  outdir
}

write_tsvs <- function(tables, file, outdir, ...) {
  file <- basename(file)
  writer <- new(J("technology.tabula.writers.TSVWriter"))
  tablesIterator <- tables$iterator()
  p <- 1L
  while (.jcall(tablesIterator, "Z", "hasNext")) {
    filename <- paste0(tools::file_path_sans_ext(file), "-", p, ".tsv")
    outfile <- normalizePath(file.path(outdir, filename), mustWork = FALSE)
    bufferedWriter <- new(
      J("java.io.BufferedWriter"),
      new(J("java.io.FileWriter"), outfile)
    )
    tab <- .jcall(tablesIterator, "Ljava/lang/Object;", "next")
    writer$write(bufferedWriter, tab)
    rm(tab)
    bufferedWriter$close()
    p <- p + 1L
  }
  outdir
}

write_jsons <- function(tables, file, outdir, ...) {
  file <- basename(file)
  writer <- new(J("technology.tabula.writers.JSONWriter"))
  tablesIterator <- tables$iterator()
  p <- 1L
  while (.jcall(tablesIterator, "Z", "hasNext")) {
    filename <- paste0(tools::file_path_sans_ext(file), "-", p, ".json")
    outfile <- normalizePath(file.path(outdir, filename), mustWork = FALSE)
    bufferedWriter <- new(
      J("java.io.BufferedWriter"),
      new(J("java.io.FileWriter"), outfile)
    )
    tab <- .jcall(tablesIterator, "Ljava/lang/Object;", "next")
    writer$write(bufferedWriter, tab)
    rm(tab)
    bufferedWriter$close()
    p <- p + 1L
  }
  outdir
}

list_matrices <- function(tables, encoding = NULL, ...) {
  out <- list()
  n <- 1L
  tablesIterator <- tables$iterator()
  while (.jcall(tablesIterator, "Z", "hasNext")) {
    nxt <- .jcall(tablesIterator, "Ljava/lang/Object;", "next")
    if (.jcall(nxt, "I", "size") == 0L) {
      break
    }
    tab <- .jcall(nxt, "Ljava/lang/Object;", "get", 0L)
    out[[n]] <- matrix(NA_character_,
      nrow = tab$getRowCount(),
      ncol = tab$getColCount()
    )
    for (i in seq_len(nrow(out[[n]]))) {
      for (j in seq_len(ncol(out[[n]]))) {
        out[[n]][i, j] <- tab$getCell(i - 1L, j - 1L)$getText()
      }
    }
    if (!is.null(encoding)) {
      Encoding(out[[n]]) <- encoding
    }
    rm(tab)
    n <- n + 1L
  }
  out
}

list_characters <- function(tables, delim = "\t", encoding = NULL, ...) {
  m <- list_matrices(tables, encoding = encoding, ...)
  lapply(m, function(x) {
    paste0(apply(x, 1, paste, collapse = delim), collapse = "\n")
  })
}

list_tibbles <- function(tables, delim = "\t", encoding = NULL, col_names = TRUE, ...) {
  char <- list_characters(tables = tables, delim = delim, encoding = encoding)
  lapply(char, function(x) {
    o <- try(read_delim(file = x, delim = delim, show_col_types = FALSE, col_names = col_names))
    if (inherits(o, "try-error")) {
      return(x)
    } else {
      return(o)
    }
  })
}