You can download the 441 page introductory Java textbook used at the University of Illinois for free at the University’s Computer Science Web site. The textbook is available as a PDF. According to US News and World Report, the University of Illinois Computer Science program is consistently ranked in the top five undergraduate programs in the United States. The textbook is excellent and an extremely useful reference guide. The textbook covers introductory material ranging from types, variables, and expressions through algorithm design, recursion, sorting, and searching.

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