The case of characters in a
String
can be changed using
toLowerCase()
or
toUpperCase()
method.
toLowerCase
method changes all the characters in the String
to lower case.
toUpperCase
method changes all the characters in the String
to upper case.
Syntax of
toLowerCase
method is :
public String toLowerCase()
or
public String toLowerCase(Locale locale)
Syntax of
toUpperCase
method is :
public String toUpperCase()
or
public String toUpperCase(Locale locale)
- The first version of these methods use a default
Locale
for case conversion i.e. it is executed internally as toLowerCase(Locale.getDefault())
.
- The second version of these methods are used for internationalization purpose, it performs case conversion with respect to the specified
Locale
.
Here is a sample program implementing these methods :
Case Conversion in a string
import java.util.Locale;
class CaseConvertDemo
{
public static void main(String arg[])
{
String str = "MeriT CampuS".toUpperCase(); // LINE A
System.out.println(str);
System.out.println(str.toLowerCase()); // LINE B
str = "turkish";
Locale locale = new Locale("tr"); // LINE C
System.out.println("String in Turkish locale is: " + str.toUpperCase(locale)); // LINE D
// System.out.println("String in default locale (English) :" + str.toUpperCase()); // LINE E
str = "TURKISH";
System.out.println("String in Turkish locale is: " + str.toLowerCase(locale)); // LINE F
// System.out.println("String in default locale (English) :" + str.toLowerCase()); // LINE G
}
}
OUTPUTMERIT CAMPUS
merit campus
String in Turkish locale is: TURKİSH
String in Turkish locale is: turkısh
DESCRIPTIONAt LINE A
, string "MeriT CampuS" is converted to uppercase resulting in "MERIT CAMPUS".
At LINE B
, str
is converted to lowercase resulting in "merit campus".
A new Locale
object is created at LINE C
. This Locale
object represents TURKEY country and TURKISH language.
Using this Locale
"turkish" is converted to uppercase at LINE D
, outputting TURKİSH.
Using this Locale
"TURKISH" is converted to lowercase at LINE F
, outputting turkısh.
THINGS TO TRY
- Comment
LINE D
and uncomment LINE E
. Here conversion is done using default Locale
i.e. English. The conversion results in TURKISH instead of TURKİSH.
- Comment
LINE F
and uncomment LINE G
. Here conversion is done using default Locale
i.e. English. The conversion results in turkish instead of turkısh.
- Try converting the strings using different
Locales
and notice the difference.