Touring Language APIs - Beginning Java 7 - page 331

• static String toBinaryString(int i) returnsa String object
containing i 's binary representation. For example, In-
teger.toBinaryString(255) returns a String object containing
11111111.
• static String toHexString(int i) returns a String object
containing i 's hexadecimal representation. For example, In-
teger.toHexString(255) returns a String object containing ff.
• static String toOctalString(int i) returns a String object
containing i 's octal representation. For example, toOctalString(64) re-
turns a String object containing 100.
• static String toString(int i) returnsa String objectcontaining
i 'sdecimalrepresentation.Forexample, toString(255) returnsa String
object containing 255.
Itisoftenconvenienttoprependzerostoabinarystringsothatyoucanalignmultiple
binarystringsincolumns.Forexample,youmightwanttocreateanapplicationthatdis-
plays the following aligned output:
11110001
+
00000111
--------
11111000
Unfortunately, toBinaryString() doesnotletyouaccomplishthistask.Forex-
ample, Integer.toBinaryString(7) returns a String object containing 111
insteadof00000111. Listing4-7 's toAlignedBinaryString() methodaddresses
this oversight.
Listing 4-7. Aligning binary strings
class AlignBinary
{
public static void main(String[] args)
{
System.out.println(toAlignedBinaryString(7, 8));
System.out.println(toAlignedBinaryString(255, 16));
System.out.println(toAlignedBinaryString(255, 7));
}