package plan9.lib; import java.lang.StringBuilder; // from styx-n-9p.googlecode.com (MIT licence)public class Base16 implements Encoding { 	private final static char[] hex = {'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B', 'C', 'D', 'E', 'F'}; 	public final String enc(byte[] a){		StringBuilder o = new StringBuilder();		for(byte b : a) {			int n = (int)b & 0xFF;			o.append(hex[n>>4]);			o.append(hex[n & 0xF]);		}		return o.toString();	} 	// this is compatible with both dec16 and strtomp on Plan 9, in handling of odd length	public final byte[] dec(String s){		int l = s.length();		byte[] a = new byte[(l+1)/2];		int o = 0;		int j = l & 1;	// add extra 0 nibble at front if odd length, equivalent to right-justifying value		int n = 0;		for(int i = 0; i < l; i++){			char c = s.charAt(i);			n <<= 4;			if(c >= '0' && c <= '9')				n |= c - '0';			else if(c >= 'A' && c <= 'F')				n |= c-'A'+10;			else if(c >= 'a' && c <= 'f')				n |= c-'a'+10;			else				continue;			if(++j == 2){				a[o++] = (byte)n;				j = n = 0;			}		}		return a;	}}