The syntax of the string toUpperCase()
method is:
string.toUpperCase()
toUpperCase() Parameters
- doesn't take any parameters
toUpperCase() Return Value
- returns a string with all lower case letters converted to upper case
Example: Java toUpperCase()
class Main {
public static void main(String[] args) {
String str1 = "Learn Java";
String str2 = "Java123";
// convert to upper case letters
System.out.println(str1.toUpperCase()); // "LEARN JAVA"
System.out.println(str2.toUpperCase()); // "JAVA123"
}
}
As you can see from the above example, toUpperCase()
converts all lower case letters to upper case letters.
toUpperCase() With Locale Parameter
The toUpperCase()
method can also take a locale as an argument. This allows you to convert all characters in a string to upper case using the given Locale (such as: Turkish, Lithuanian etc.) rules.
Its syntax is:
string.toUpperCase(Locale locale)
If you do not pass the locale
parameter, the default locale, Locale.getDefault()
, is used.
To learn more, visit Java toUpperCase() With Locale.
To convert all characters in a string to lower case letters, use the Java String toLowerCase() method.