Data Structures and Algorithms in Java[1].pdf - Fulvio Frisone

The cells of this new array, "a," are indexed using the integer set {0,1,2,… ,9}
(recall that arrays in Java always start indexing at 0), and, like every array in Java,
all the cells in this array are of the same type—double.
1.5.2 Arrays are Objects
Arrays in Java are special kinds of objects. In fact, this is the reason we can use the
new operator to create a new instance of an array. An array can be used just like
any general object in Java, but we have a special syntax (using square brackets, "["
and "]") to refer to its members. An array in Java can do everything that a general
object can. Since an array is an object, though, the name of an array in Java is
actually a reference to the place in memory where the array is stored. Thus, there is
nothing too special about using the dot operator and the instance variable, length, to
refer to the length of an array, for example, as "a.length." The name, a, in this
case is just a reference, or pointer, to the underlying array object.
The fact that arrays in Java are objects has an important implication when it comes
to using array names in assignment statements. For when we write something like
b = a;
in a Java program, we really mean that b and a now both refer to the same array.
So, if we then write something like
b[3] = 5;
then we will also be setting the number a [3] to 5. We illustrate this crucial point in
Figure 1.7.
Figure 1.7: An illustration of an assignment of array
objects. We show the result of setting "b[3] = 5;"
after previously setting "b = a;".
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