package thinkinginjava.containers;

// Demonstration of BitSet.

import java.util.*;

import static thinkinginjava.util.Print.*;

public class Bits {

public static void printBitSet(BitSet b) {

print("bits: " + b);

StringBuilder bbits = new StringBuilder();

for (int j = 0; j < b.size(); j++)

bbits.append(b.get(j) ? "1" : "0");

print("bit pattern: " + bbits);

}

public static void main(String[] args) {

Random rand = new Random(47);

// Take the LSB of nextInt():

byte bt = (byte) rand.nextInt();

BitSet bb = new BitSet();

for (int i = 7; i >= 0; i--)

if (((1 << i) & bt) != 0)

bb.set(i);

else

bb.clear(i);

print("byte value: " + bt);

printBitSet(bb);

short st = (short) rand.nextInt();

BitSet bs = new BitSet();

for (int i = 15; i >= 0; i--)

if (((1 << i) & st) != 0)

bs.set(i);

else

bs.clear(i);

print("short value: " + st);

printBitSet(bs);

int it = rand.nextInt();

BitSet bi = new BitSet();

for (int i = 31; i >= 0; i--)

if (((1 << i) & it) != 0)

bi.set(i);

else

bi.clear(i);

print("int value: " + it);

printBitSet(bi);

// Test bitsets >= 64 bits:

BitSet b127 = new BitSet();

b127.set(127);

print("set bit 127: " + b127);

BitSet b255 = new BitSet(65);

b255.set(255);

print("set bit 255: " + b255);

BitSet b1023 = new BitSet(512);

b1023.set(1023);

b1023.set(1024);

print("set bit 1023: " + b1023);

}

}