Java Program for Website Crawling

I'm in need of a Java program that can crawl specific websites and extract text content. The program will be required to crawl between 1 to 5 specified sites.

Ideal Skills:
- Proficient in Java programming
- Experience in web crawling
- Familiarity with data extraction techniques
- Able to handle and process text content efficiently
- Knowledge of best practices for web crawling to avoid overloading the server or violating robots.txt rules.

Please note that the primary task of this program is to collect text content from these websites.