I am looking to create a crawler in Java that can navigate through web pages and extract specific information from the content. Can anyone provide guidance on how I can start building this type of crawler?
For instance, how could I retrieve the statement "red is my favorite color" from a webpage when it is contained within HTML tags like the following:
<div>red is my favorite color</div>
Recommended reading material
For static web pages:
jsoup - tool for parsing HTML and manipulating content
Keep in mind that many pages generate content dynamically using JavaScript after they have loaded. In such cases, the "static page" method may not be sufficient, and you may need to explore tools in the "Web automation" field.
Selenium is one such toolset that allows you to control your browser to open and navigate pages using a regular browser or even a 'headless' browser like PhantomJS.
Best of luck as you dive into the world of reading and coding.
[edited for illustrative purposes]
This process is known as Web scraping - search online for examples using Google. The following are just a few results from my own searches, provided without any warranties or endorsements:
For "scraping static webpages" - check out this example using jsoup
For dynamic pages - here's an example utilizing Selenium
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