Java Reference
In-Depth Information
The values for n1 and n2 are
swapped, but it does not affect
num1 and num2.
The values of
num1
and
num2
are
passed to
n1
and
n2
.
Space required for the
swap
method
Space required for the
swap
method
temp:
temp:
n2: 2
n1: 1
n2: 1
n1: 2
Space required for the
main
method
Space required for the
main
method
Space required for the
main
method
Space required for the
main
method
Stack is empty
num2: 2
num1: 1
num2: 2
num1: 1
num2: 2
num1: 1
num2: 2
num1: 1
The
swap
method
is finished.
The
main
method
is invoked.
The
swap
method
is invoked.
The
swap
method
is executed.
The
main
method
is finished.
F
IGURE
5.4
The values of the variables are passed to the method's parameters.
Note
For simplicity, Java programmers often say
passing
x
to
y
, which actually means
passing
the value of argument
x
to parameter
y
.
5.11
✓
✓
How is an argument passed to a method? Can the argument have the same name as its
parameter?
Check
Point
5.12
Identify and correct the errors in the following program:
1
public class
Test {
2
public static void
main(String[] args) {
3 nPrintln(
5
,
"Welcome to Java!"
);
4 }
5
6
public static void
nPrintln(String message,
int
n) {
7
int
n =
1
;
8
for
(
int
i =
0
; i < n; i++)
9 System.out.println(message);
10 }
11 }
5.13
What is pass-by-value? Show the result of the following programs.
public class
Test {
public static void
main(String[] args) {
int
max =
0
;
max(
1
,
2
,
max);
System.out.println(max);
public class
Test {
public static void
main(String[] args) {
int
i =
1
;
while
(i <=
6
) {
method1(i,
2
);
i++;
}
}
public static void
max(
int
value1,
int
value2,
int
max) {
if
(value1 > value2)
max = value1;
else
max = value2;
}
public static void
method1(
int
i,
int
num) {
for
(
int
j =
1
;
j <= i; j++) {
System.out.print(num +
" "
);
num *=
2
;
}
}
}
System.out.println();
}
}
(a)
(b)
