Java IO.pdf - Nguyen Dang Binh

Java I/O
two Latin letters. In uppercase they are D , LJ, NJ, and DZ. In lowercase they are d , lj, nj,
and dz. In title case they are D , Lj, Nj, and Dz. The isUpperCase() method returns true if
the specified character is defined as uppercase; isLowerCase()returns true if the specified
character is defined as lowercase; and isTitleCase()returns true if the specified character
is defined as title case by the Unicode specification.
public static boolean isLowerCase(char c)
public static boolean isUpperCase(char c)
public static boolean isTitleCase(char c)
Many characters are neither uppercase nor lowercase. For instance, both
Character.isLowerCase('7') and Character.isUpperCase('7') return false. The
Devanagari script used for Hindi, Sanskrit, and some other languages of the Indian
subcontinent does not have upper- and lowercases. The toUpperCase(), toLowerCase(), and
toTitleCase() methods return the upper-, lower-, and title case equivalents of the specified
character:
public static char toLowerCase(char c)
public static char toUpperCase(char c)
public static char toTitleCase(char c)
For example:
character upperA = Character.toUpperCase('a');
Not all letters and certainly not all characters have upper-, lower-, or title case equivalents. If
the specified character does not have an upper-, lower-, or title case equivalent, then the
unmodified character itself is returned.
The isDigit() method returns true if its argument is a digit in any character set. This
includes not just the usual ASCII digits through 9 but digits from Arabic, Devanagari,
Bengali, Gurmukhi, Gujarati, Oriya, Tamil, Telugu, Kannada, Lao, Malayalam, Thai, and
Tibetan.
public static boolean isDigit(char ch)
The isLetterOrDigit() method returns true if the specified character is either a Unicode
letter or a Unicode digit as determined by the isLetter() and isDigit() methods:
public static boolean isLetterOrDigit(char c)
The isSpaceChar() method returns true if Unicode defines the specified character as a
space character:
public static boolean isSpaceChar(char c)
Space characters include ASCII spaces (32) but do not include some characters you might
expect, like carriage returns, tabs, or linefeeds.
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