Java Reference
In-Depth Information
45
46
// test regionMatches (case sensitive)
47
if
(
s3.regionMatches(
0
, s4,
0
,
5
)
)
48
System.out.println(
"First 5 characters of s3 and s4 match"
);
49
else
50
System.out.println(
51
"First 5 characters of s3 and s4 do not match"
);
52
53
// test regionMatches (ignore case)
54
if
(
s3.regionMatches(
true
,
0
, s4,
0
,
5
)
)
55
System.out.println(
56
"First 5 characters of s3 and s4 match with case ignored"
);
57
else
58
System.out.println(
59
"First 5 characters of s3 and s4 do not match"
);
60
}
61
}
// end class StringCompare
s1 = hello
s2 = goodbye
s3 = Happy Birthday
s4 = happy birthday
s1 equals "hello"
s1 is not the same object as "hello"
Happy Birthday equals happy birthday with case ignored
s1.compareTo(s2) is 1
s2.compareTo(s1) is -1
s1.compareTo(s1) is 0
s3.compareTo(s4) is -32
s4.compareTo(s3) is 32
First 5 characters of s3 and s4 do not match
First 5 characters of s3 and s4 match with case ignored
Fig. 14.3
|
String
methods
equals
,
equalsIgnoreCase
,
compareTo
and
regionMatches
.
(Part 2 of 2.)
String
Method
equals
The condition at line 17 uses method
equals
to compare
String
s1
and the
String
literal
"hello"
for equality. Method
equals
(a method of class
Object
overridden in
String
)
tests any two objects for equality—the strings contained in the two objects are
identical
.
The method returns
true
if the contents of the objects are equal, and
false
otherwise.
The preceding condition is
true
because
String
s1
was initialized with the string literal
"hello"
. Method
equals
uses a
lexicographical comparison
—it compares the integer
Unicode values (see online Appendix H for more information) that represent each charac-
ter in each
String
. Thus, if the
String
"hello"
is compared to the string
"HELLO"
, the
result is
false
, because the integer representation of a lowercase letter is
different
from that
of the corresponding uppercase letter.
