The Object of Java fully embraces the object-oriented paradigm by taking an objects-centric approach to presenting problem solving and programming. Readers begin with four complete chapters focusing on objects, classes and methods. The presentation of primitive data occurs in Chapter 5, ensuring the necessary prior exposure to object declaration, object instantiation, assignment, method calling, parameter passage, class diagrams and object diagrams. The topics of aggregation and inheritance occur earlier than in many other CS1 books. In order to accommodate this placement of topics, control structures are covered later than in other books. Through many semesters of class-testing this objects-centric approach, students have developed a high degree of competence with both object-oriented features and the classic language features such as numeric expressions and control structures. This book focuses on the skills and disciplines of software engineering that are needed for good programming. Since specifications are critical for conveying code behavior in the object-oriented model, discussions of method preconditions and postconditions, and class invariants are used consistently to document examples and to define example classes. The Unified Modeling Language is used extensively as the specification language. The book also uses the notion of patterns to identify numerous expressions, instructions, algorithms and designs that serve to pattern program segments. This BlueJ version integrates the use of BlueJ throughout the presentation. Explanation of BlueJ facilities for programming, testing and debugging are included along with these topical discussions. An appendix that demonstrates key BlueJ features is also included.Riley, David D. is the author of 'Object of Java, Bluej Edition Introduction to Java Using Software Engineering Principles' with ISBN 9780321168542 and ISBN 0321168542.