Java Reference
In-Depth Information
•
The indexed variables of an array can be used as an argument to be plugged in for
a parameter of the array's base type.
•
A method can have parameters of an array type. When the method is invoked, an
entire array is plugged in for the array parameter.
•
A method may return an array as the value returned by the method.
•
When using a partially filled array, your program needs an additional variable of
type
int
to keep track of how much of the array is being used.
•
An instance variable of a class can be of an array type.
•
If you need an array with more than one index, you can use a multidimensional
array, which is actually an array of arrays.
Answers to Self-Test Exercises
1. a.
word
b.
String
c.
5
d.
0
through
4
inclusive
e. Any of the following would be correct:
word[0]
,
word[1]
,
word[2]
,
word[3]
,
word[4]
2. a.
10
b.
0
c.
9
3.
a, b, c,
4.
1.1 2.2 3.3
1.1 3.3 3.3
5.
The
for
loop uses indices
1
through
sampleArray.length
, but the correct indices
are
0
through
sampleArray.length
−
1
. The last index,
sampleArray.length
, is
out of bounds. What was probably intended is the following:
int
[] sampleArray =
new int
[10];
for
(
int
index = 0; index < sampleArray.length; index++)
sampleArray[index] = 3*index;
6.
The last value of
index
is
a.length
−
1
, which is the last index of the array. How-
ever, when
index
has the value
a.length
−
1
,
a[index
+
1]
has an index that is
out of bounds because
index
+
1
is one more than the largest array index. The
for
loop ending condition should instead be
index
<
a.length
−
1
.
