Sams Teach Yourself C in 21 Days

If, however, the array is of an object type, you must explicitly initialize each element of

the array with a reference to an object:

MyClass ClassArray = new MyClass [10];

for (int i=0; i<10; i++) {

ClassArray[i] = new MyClass; }

Java arrays can have more than one dimension. Multidimensional arrays are created by

using one set of brackets for each dimension, with the same syntax as described above

for a one-dimensional arrays:

int twoDimensionalArray [][] = new int[10][5];

byte fourDimensionalArray [][][][];

fourDimensionalArray = new byte[4][4][5][5];

716 Bonus Day 4

Java arrays start with element 0, and not element 1 as you might think.

Thus, an array with 100 elements has elements [0] through [99], and trying

to use element [100] does not work. If you want an nelement array with

elements [1] through [n]–for example, days[1] through days[365] to refer to

the days of the year—your only choice is to create an array 1 element larger

than needed and ignore element [0].

Caution

Operators ............................................................................................................

Anoperatoris a symbol that performs some operation on data, such as adding and sub-

tracting. You have already met the assignment operator (=), which is used to assign val-

ues. For the most part, operators in Java are identical to those in C and C++. Java has the

standard arithmetic operators for addition (+), subtraction (-), multiplication (*), division

(/), and modulus (%). And, like C and C++, Java offers the unary increment (++) and

decrement (--) operators which, respectively, increase and decrease an integer value by

1. Rounding out the mathematical operators are the assignment with operators +=,-=,=,
   and/=, which provide a shorthand for operating on the contents of variables. For exam-
   ple:
   x += 5 ; // Same as x = x + 5;
   y = 1.5; // Same as y = y * 1.5;
   Java’s comparison operators are also the same as those in C and C++: equal to (==), not
   equal to (!=), greater than (>), greater than or equal t0 (>=), less than (<), less than or
   equal to (<=).
   Finally, Java’s logical operators are also the same as you have learned before: NOT (!),
   AND (&&), and OR (||).

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