tabula-java is a library for extracting tables from PDF files — it is the table extraction engine that powers Tabula (repo). You can use tabula-java as a command-line tool to programmatically extract tables from PDFs.
© 2014-2020 Manuel Aristarán. Available under MIT License. See LICENSE.
DrugBank maintains a forked copy of tabula-java. W e forked tabula-java quite a while ago to add features that would help when extracting EMA product information from pdfs. We made a few changes, some of which were contributed back upstream, and some of which are very specific to our use case and have been kept private.
This version includes multiple features that we have developed but not upstreamed. Our strategy to keep merges simple is to keep feature branches which are updated individually. Each feature branch should include the minimal amount of changes possible. This way, each merge conflict should be as easy as possible to resolve.
See #1 for more info about how this strategy was developed and chosen.
If you haven't yet, add the upstream remote.
git remote add upstream [email protected]:tabulapdf/tabula-java.git
Because we have feature branches which have not been pushed upstream, we use a strategy of maintaining those feature branches over time. This makes it easier to resolve conflicts as they can be considered in isolation as part of a single feature.
Repeat the following procedure for each feature branch:
git pull upstream master- fix merge issue
- run
mvn testand fix any issues that appear git checkout mastergit mergethe branch you just updated
mvn test && mvn compile- publish release to tabula-java repo
- download the new jar to vendor/tabula-java/ in the main DrugBank repo and include its version number in the filename
- edit
Pipeline::Tools::Ema::PdfToJsonto use the new version - Test the new version of
tabula-javain QA with theema_products:check_all_package_pdfsrake task
tabula-java provides a command line application:
$ java -jar target/tabula-1.0.5-jar-with-dependencies.jar --help
usage: tabula [-a <AREA>] [-b <DIRECTORY>] [-c <COLUMNS>] [-f <FORMAT>]
[-g] [-h] [-i] [-l] [-n] [-o <OUTFILE>] [-p <PAGES>] [-r] [-s
<PASSWORD>] [-t] [-u] [-v]
Tabula helps you extract tables from PDFs
-a,--area <AREA> -a/--area = Portion of the page to analyze.
Example: --area 269.875,12.75,790.5,561.
Accepts top,left,bottom,right i.e. y1,x1,y2,x2
where all values are in points relative to the
top left corner. If all values are between
0-100 (inclusive) and preceded by '%', input
will be taken as % of actual height or width
of the page. Example: --area %0,0,100,50. To
specify multiple areas, -a option should be
repeated. Default is entire page
-b,--batch <DIRECTORY> Convert all .pdfs in the provided directory.
-c,--columns <COLUMNS> X coordinates of column boundaries. Example
--columns 10.1,20.2,30.3. If all values are
between 0-100 (inclusive) and preceded by '%',
input will be taken as % of actual width of
the page. Example: --columns %25,50,80.6
-f,--format <FORMAT> Output format: (CSV,TSV,JSON). Default: CSV
-g,--guess Guess the portion of the page to analyze per
page.
-h,--help Print this help text.
-ha,--detect-horizontal-alignment Detect horizontal alignment of text to
improve column detection.
-i,--silent Suppress all stderr output.
-pn,--rm-page-numbers Attempt to remove page numbers
-l,--lattice Force PDF to be extracted using lattice-mode
extraction (if there are ruling lines
separating each cell, as in a PDF of an Excel
spreadsheet)
-n,--no-spreadsheet [Deprecated in favor of -t/--stream] Force PDF
not to be extracted using spreadsheet-style
extraction (if there are no ruling lines
separating each cell)
-o,--outfile <OUTFILE> Write output to <file> instead of STDOUT.
Default: -
-p,--pages <PAGES> Comma separated list of ranges, or all.
Examples: --pages 1-3,5-7, --pages 3 or
--pages all. Default is --pages 1
-r,--spreadsheet [Deprecated in favor of -l/--lattice] Force
PDF to be extracted using spreadsheet-style
extraction (if there are ruling lines
separating each cell, as in a PDF of an Excel
spreadsheet)
-s,--password <PASSWORD> Password to decrypt document. Default is empty
-t,--stream Force PDF to be extracted using stream-mode
extraction (if there are no ruling lines
separating each cell)
-u,--use-line-returns Use embedded line returns in cells. (Only in
spreadsheet mode.)
-v,--version Print version and exit.
It also includes a debugging tool, run java -cp ./target/tabula-1.0.5-jar-with-dependencies.jar technology.tabula.debug.Debug -h for the available options.
You can also integrate tabula-java with any JVM language. For Java examples, see the tests folder.
JVM start-up time is a lot of the cost of the tabula command, so if you're trying to extract many tables from PDFs, you have a few options for speeding it up:
- the -b option, which allows you to convert all pdfs in a given directory
- the drip utility
- the Ruby, Python, R, and Node.js bindings
- writing your own program in any JVM language (Java, JRuby, Scala) that imports tabula-java.
- waiting for us to implement an API/server-style system (it's on the roadmap)
Clone this repo and run:
mvn clean compile assembly:single
Interested in helping out? We'd love to have your help!
You can help by:
- Reporting a bug.
- Adding or editing documentation.
- Contributing code via a Pull Request.
- Spreading the word about
tabula-javato people who might be able to benefit from using it.
You can also support our continued work on tabula-java with a one-time or monthly donation on OpenCollective. Organizations who use tabula-java can also sponsor the project for acknowledgement on our official site and this README.
Special thanks to the following users and organizations for generously supporting Tabula with donations and grants:
