An indepth guide on how to write idiomatic scala code. Symbols used in this document the text accompanying the three hazard symbols danger, warning and caution is structured in the following way. Here we will look into scala read file and scala write file programs. Scala reference manuals the scala programming language. You will also learn how to browse the scaladoc documentation at a beginners level. It seamlessly integrates features of objectoriented and functional languages. Note that templates are compiled with different default imports. An excellent stepbystep introduction to many of the scala features with the help of simple code examples.
The quickest way to find out about some of these is to check out this tutorial video. Scala enables you to use all the classes of the java sdk and also your own custom java classes, or your favorite java open source projects. Even though i import all the jars as did in java there comes a problem with itext. Scala template code samples should be tested either with specs in scala or junit in java. File operations mainly include reading data from files or writing data into files. As with all style guides, treat this document as a list of. Slides pdf 20925 scaling scala to the database javaone 20, san francisco, ca, usa. Read and generate pdf in java itext tutorial howtodoinjava. A universal document scraper in scala by bozhidar bozhanov. I have already done pdf generation from html in java and it worked fine. On these webpages i try to collect all the scala documentation you need for the courses that i teach cs109 and cs206.
It reduces the number of lines and helps the programmer to code in a typesafe way. Unfortunately, there is not yet much documentation for scala that is really usable for beginners in programming. The type of document pdf, doc or html and the type of the scraping workflow. With each java pdf example, i have attached a snapshot of pdf file so that you can visualize what.
Converting pdf content to plain text with scala or java. Introduction to scala and spark sei digital library. This demonstrates some basic differences from java. Scala, java, python and r examples are in the examples srcmain directory. This book is available in both paper and pdf ebook form. It is based on the flying saucer library, which in turn uses itext for pdf generation. This document introduces scala in an informal way, through a sequence of examples. Also very importantly, it uses the apache pdfbox library to read pdf files and extract their text. The functional implementation makes it look like scala is a language thats specialized for functional operations on arrays. I am migrating a java service to a scala micro service and i want to be able to generate html documents and send them in an email or store them as pdf files. Martin odersky is the creator of the scala language and a professor at epfl in. To generate scaladoc api documentation, document your code using scaladoc tags, and then create the documentation using an sbt.
This end to end pipeline is capable of predicting the unknown classes of different text with decent accuracies. In this chapter, you will learn how to use scala as an industrialstrength pocket calculator, working interactively with numbers and arithmetic operations. As with all style guides, treat this document as a list of rules to be broken. Java libraries and frameworks can be used without glue code or additional declarations. Wherever possible, this guide attempts to detail why a particular style is encouraged and how it relates to other alternatives. In this itext tutorial, i am writing various code examples read a pdf file and generate pdf file. I just chose end because it makes the most sense to me. Ive also written a scala shell script to do the same thing convert the pages from a pdf file to plain text. This example extracts the text contents of a pdf for use in other systems. Scala is a modern multiparadigm programming language designed to express common programming patterns in a concise, elegant, and typesafe way. Scala by example learn scala through a series of examples. A list of frequentlyasked questions about scala language features and their answers. You want to update one or more documents in a mongodb collection in a scala application solution. You can create an empty pdf document by instantiating the document class.
Install scala on your computer and start writing some scala code. While instantiating this class, you need to pass a pdfdocument object as a parameter to its constructor following are the steps to create an empty pdf document. To run one of the java or scala sample programs, use binrun example params in the toplevel spark directory. It provides highlevel apis in java, scala, python and r, and an optimized engine that supports general execution graphs. This module helps in generating pdf documents dynamically from your scala application. The source code for this project is written in scala, and the gui uses akka actors to help keep the gui from coming to a screaming halt when the pdf file is read. It simply renders your html and cssbased templates to pdf. The document scala by example about 150 pages, available in pdf format contains more advanced scala examples. Your contribution will go a long way in helping us. For reading a file, we have created a test file with below content. For example, an application form for driving license or something along those lines. Let us now understand how to create a pdf document using the itext library. Readwrite in excel sheet using apache poi with scala.
Using the scaladoc interface scaladoc scala documentation. In this tutorial, well walk you through downloading and setting up intellij with the scala plugin, and well get you started with your first scala project, complete with unit tests. The example for how to transform a directory of input files into a pdf file looks the same. A handy cheatsheet covering the basics of scala s syntax. Create a pdf generator factory method in your applications guice module.
This page is a work in progress, but as ive been learning scala, ive been creating all sorts of little notes, and im now trying to organize them into this scala cheat sheet. I have used the apache poi library to parse and create ms word documents including docx files. This is a little dated, but i hope its still helpful. If you need a comprehensive and easy to follow manual for the scala language, the book programming in scala is the canonical reference text. As a first example, here is an implementation of quicksort in scala. Apache spark is a fast and generalpurpose cluster computing system.
Finally, the following ressources contain scala examples as well. Document classification using apache spark in scala. Scala is a pure objectoriented language in the sense that every value is an object. This tutorial will walk through how to easily work with files in the scala programming language, in a way that scales from interactive usage in the repl, to your first scala. Intellij is the most commonlyused ide by scala developers. This document is a scala cheat sheet reference page, in html format. In my github project youll find a shell script to compile the application into a native mac os x application. It also supports a rich set of higherlevel tools including spark sql for sql and structured data processing, mllib for machine learning, graphx for graph. Youve annotated your scala code with scaladoc, and you want to generate developer documentation for your api solution.
Indepth documentation covering many of scala s features. Chapters2and3highlight some of the features that make scala interesting. We include the spark documentation as part of the source as opposed to using a hosted wiki, such as the github wiki, as the definitive documentation to enable the documentation to evolve along with the source code. Working with files and the filesystem is one of the most common things you do when programming. A universal document scraper in scala dzone big data. An online book introducing the main language features. Rubin, phd director, center of excellence for big data graduate programs in software university of st. Many scala developers, including those with a great deal of experience, are unaware of some of the more powerful features of scaladoc. Indepth documentation covering many of scalas features. Cay horstmann introduces a number of important scala concepts and idioms along the way. Scala examples advanced the scala programming language. The full code of this tutorial can be found here, this tutorial explains about creating a pipeline for document classification in spark using scala. Create pdfs from scala using plain old html and css.
Uses wkhtmltopdf on the backend which renders html using webkit. The scala distribution contains a directory examples with other source examples. A preprint is a workinprogress, a book that has not yet been fully. Yes, you read the title it right using apache poi, you can easily read and write in an ms excel file using javascala so, before we get started with the implementation, lets have a quick. How to generate scala documentation with the scaladoc. The backend will have the format information about the document to be generated and other information will be gathered from user from frontend. Many of the initial notes were based on the excellent book, programming. This document is intended to outline some basic scala stylistic guidelines which should be followed with more or less fervency. For example, we could extend our readme example by filtering the lines in the file that contain a word, such as python, as shown in example 24 for python and example 25 for scala. These examples are extracted from open source projects.
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