Java Reference
In-Depth Information
toHexString(packed));
// Now unpack the letters and output them
long mask = 0xFFFF;
// Rightmost 16 bits as 1
char letter = (char)(packed & mask);
// Extract the rightmost
letter
System.out.println("From right to left the letters in packed
are:");
System.out.println(" " + letter + " 0x" + toHexString(letter));
packed >>= 16;
// Shift out the rightmost
letter
letter = (char)(packed & mask);
// Extract the new
rightmost letter
System.out.println(" " + letter + " 0x" + toHexString(letter));
packed >>= 16;
// Shift out the rightmost
letter
letter = (char)(packed & mask);
// Extract the new
rightmost letter
System.out.println(" " + letter + " 0x" + toHexString(letter));
packed >>= 16;
// Shift out the rightmost
letter
letter = (char)(packed & mask);
// Extract the new
rightmost letter
System.out.println(" " + letter + " 0x" + toHexString(letter));
}
}
The output from this example is the following:
packed now contains 0x44004300420041
From right to left the letters in packed are:
A 0x41
B 0x42
C 0x43
D 0x44
How It Works
The first four statements in
main()
define variables initialized with the letters to be packed into the vari-
able,
packed
, of type
long
that is defined in the fifth statement in
main()
. The packing process begins
by storing the first character in
packed
:
packed = letterD; // Store D
The rightmost 16 bits in
packed
now contain the character code
D
. This eventually ends up in the leftmost
16 bits of
packed
. The next statement inserts the next letter,
C
, into packed:
packed = (packed << 16) | letterC; // Shift and add the next
letter - C
