//: containers/Bits.java // ©2015 MindView LLC: see Copyright.txt // Demonstration of BitSet. import java.util.*; import static net.mindview.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); } } /* Output: byte value: -107 bits: {0, 2, 4, 7} bit pattern: 1010100100000000000000000000000000000000000000000000000000000000 short value: 1302 bits: {1, 2, 4, 8, 10} bit pattern: 0110100010100000000000000000000000000000000000000000000000000000 int value: -2014573909 bits: {0, 1, 3, 5, 7, 9, 11, 18, 19, 21, 22, 23, 24, 25, 26, 31} bit pattern: 1101010101010000001101111110000100000000000000000000000000000000 set bit 127: {127} set bit 255: {255} set bit 1023: {1023, 1024} *///:~