Converting Between Unicode Characters and Strings
Problem
You want to convert between Unicode characters and
Strings.
Solution
Since both
Java
chars and Unicode
characters are
16 bits in width, a char can hold any Unicode
character. The charAt( )
method of String returns a Unicode character. The
StringBuffer
append( ) method
has a form that accepts a char. Since
char is an integer type, you can even do
arithmetic on chars,
though this is not necessary as frequently as in, say, C. Nor is it
often recommended, since the
Character
class provides the methods for which
these operations were normally used in languages such as C. Here is a
program that uses arithmetic on chars to control a
loop, and also appends the characters into a
StringBuffer (see Section 3.4):
/**
* Conversion between Unicode characters and bytes
*/
public class UnicodeChars {
public static void main(String[] argv) {
StringBuffer b = new StringBuffer( );
for (char c = 'a'; c<'d'; c++) {
b.append(c);
}
b.append('\u00a5'); // Japanese Yen symbol
b.append('\u01FC'); // Roman AE with acute accent
b.append('\u0391'); // GREEK Capital Alpha
b.append('\u03A9'); // GREEK Capital Omega
for (int i=0; i<b.length( ); i++) {
System.out.println("Character #" + i + " is " + b.charAt(i));
}
System.out.println("Accumulated characters are " + b);
}
}When you run it, the expected results are printed for the ASCII characters. On my Unix system, the default fonts don’t include all the additional characters, so they are either omitted ...