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Each Java variable or expression has a definite type, given by a declaration such as"int i;". There are three "types" of types!
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There are Primitive or Simple types such as integers or booleans which are built-in.
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New composite types (objects) can be constructed in terms of classes and interfaces. The type of an object is its class or interface
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Arrays we will see are a sort of "almost" object!
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First we discuss the Primitive Types
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There are 4 integer types: byte, short, int, long of size 8, 16, 32 and 64 bits, respectively.
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float is 32 bits, double is 64 bits. Floating point arithmetic and data formats are defined by IEEE754 standard.
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characters are given by 16bit Unicode charset and represented as short integers.
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One can use casts for conversion such as longint = (long) i; // which can be explicit as here and sometimes implied (see later)
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Note booleans are either TRUE or FALSE -- they are not 0, 1 ,-1 ...
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