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/** | |
* Generates EAN13 barcode data | |
* | |
* @author cab404 | |
*/ | |
public class EAN13 { | |
public static final int[] INDENTS = {0, 2, 44, 46, 92, 94}; | |
public static final int LENGTH = 95; | |
private final static byte[][] CODEMAP = | |
{ | |
{13, 25, 19, 61, 35, 49, 47, 59, 55, 11}, | |
{39, 51, 27, 33, 29, 57, 5, 17, 9, 23}, | |
{114, 102, 108, 66, 92, 78, 80, 68, 72, 116} | |
}; | |
private final static byte FILLMAP[] = { | |
0, 52, 44, 28, 50, 38, 14, 42, 26, 22 | |
}; | |
private final static byte PADDING = 5; | |
private final static byte DIV = 10; | |
byte[] data = new byte[13]; | |
public String form(String from) { | |
if (from.length() != 13) | |
throw new NumberFormatException(); | |
for (int i = 0; i < from.length(); i++) | |
if (!Character.isDigit(from.charAt(i))) | |
throw new NumberFormatException(); | |
else | |
data[i] = (byte) (from.charAt(i) - '0'); | |
StringBuilder builder = new StringBuilder(); | |
byte head = data[0]; | |
decode(PADDING, 3, builder); | |
for (int i = 1; i < 7; i++) | |
decode(CODEMAP[(FILLMAP[head] & (1 << i - 1)) >> i - 1][data[i]], 7, builder); | |
decode(DIV, 5, builder); | |
for (int i = 7; i < 13; i++) | |
decode(CODEMAP[2][data[i]], 7, builder); | |
decode(PADDING, 3, builder); | |
return builder.toString(); | |
} | |
private char[] decoded = new char[8]; | |
private void decode(byte code, int len, StringBuilder to) { | |
int offset = 1; | |
int last = 7; | |
for (int i = 7; i >= 0; i--) { | |
decoded[i] = (code & offset) > 0 ? '1' : '0'; | |
last = decoded[i] == '1' ? i : last; | |
offset <<= 1; | |
} | |
to.append(decoded, 8 - len, len); | |
} | |
} |
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