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Teach Yourself Java in 21 Days, Eighth Edition

Teach Yourself Java in 24 Hours, Eighth Edition

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Day 20: Reading and Writing Data using JDBC

Certification Practice

Each chapter of the book ends with a Certification Practice question that's comparable to what you could expect to be asked on a Java certification test. Here's the answer for chapter 20:

Answer (a) is correct. The compiler fails with the error message "non-static variable count cannot be referenced from a static context."

Answer (b) is incorrect. You can use the new operator along with the constructor method of a class anywhere an object of that class would be expected.

Answer (c) is incorrect. The [] that is used to declare an array can be placed after the variable name instead of the class or data type.

Answer (d) is incorrect. Class variables can be declared anywhere outside of the methods of a class, not just at the top of the class definition.

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