Programmer's Guide to Java™ Certification, A: A Comprehensive Primer, Second Edition

3.3. Conversions

In this section we discuss the different kinds of type conversions and list the contexts in which these can occur. Some type conversions must be explicitly stated in the program, while others are done implicitly. Some type conversions can be checked at compile time to guarantee their validity at runtime, while others will require an extra check at runtime.

Unary Cast Operator: (type)

Java, being a strongly typed language, checks for type compatibility (i.e., checks if a type can substitute for another type in a given context) at compile time. However, some checks are only possible at runtime (for example, which type of object a reference actually denotes during execution). In cases where an operator would have incompatible operands ...