C.13. Primitive Types

The table in Appendix L lists the eight primitive types in Java. Like its predecessor languages C and C++, Java requires all variables to have a type. For this reason, Java is referred to as a strongly typed language.

In C and C++, programmers frequently have to write separate versions of programs to support different computer platforms, because the primitive types are not guaranteed to be identical from computer to computer. For example, an int value on one machine might be represented by 16 bits (2 bytes) of memory, on a second machine by 32 bits (4 bytes) of memory, and on another machine by 64 bits (8 bytes) of memory. In Java, int values are always 32 bits (4 bytes).

Each type in Appendix L is listed with its size in bits (there are eight bits to a byte) and its range of values. Because the designers of Java want to ensure portability, they use internationally recognized standards for character formats (Unicode; for more information, visit www.unicode.org) and floating-point numbers (IEEE 754; for more information, visit grouper.ieee.org/groups/754/).