If you intend to use Java, one of the famous programming languages, you should consider which libraries you want to use for web scraping. Each library may have its ups and downs. By the way, for those who are new, libraries in programming language refer to a set of commands, functions, and predefined methods. For a simple demonstration, the sqrt() method is in Math class, which is, in turn, is included in the "java.lang" package, and java.lang is a subset of Java Class Library.
Web Scraping with Java
Collecting a large amount of data from the websites into file formats like XLS, CSV, JSON, or TXT is the simplest possible definition of best web scraping services. Even if you can do scraping manually, most consumers prefer automatic systems. Some even prefer website scraper online solutions. You cannot do a manual scraping because it requires a vast amount of time and energy. However, when you order a web scraper online, the cost is worth the value of what you get as a final result. So, what about web scraping with Java? Users of the internet are familiar with Java programming language, but they may not be familiar with the libraries, especially scraping related ones. They mostly differ in the documentation, support type, community, or whether paid or free.
Java Library Types for Scraping
Let's analyze some Java libraries used for scraping. It is not easy to write a thorough analysis of each, but we aim to get a basic idea for each library.
Its capability to cope is relatively high, can function well under developing workload. Being efficient is the core aim of Apache Nutch. It has excellent documentation, a very active community in its development, and above all, free to use. Also, it receives regular updates, and the last update was in July 2020. Since it offers rich features, it will not be exaggerating to say that many Java developers prefer it. It also complies with the robots.txt, a file that shows search scrapers which pages it can or can't request from that site.
Having more than 650 stars on GitHub gives StormCrawler credibility. Its Software Development Kit is open-source and based on Apache Storm. It is excellently suitable to use when the URL to fetch and parse come as streams. Moreover, StormCrawler is also an appropriate answer for massive recursive crawls, especially for cases that involve low latency. It has an active community and free as well.
Verdict for the libraries
It is always easy to tell people to choose anything from the set according to your needs. However, in our case, Apache Nutch is a winner. Other libraries offer their best as well. Yet, having a great support community, one of the best documentation and support, and being free makes Apache Nutch a champion.