/**
* Scans a PEReference. [69]
*
* @return entity
* @throws IOException I/O exception
*/
private byte[] peRef() throws IOException {
// scans predefined entities
final byte[] name = name(true);
consume(';');
final byte[] en = pents.get(name);
if (en != null) return en;
return name;
}
/**
* Scans a reference. [67]
*
* @param f dissolve entities
* @return entity
* @throws IOException I/O exception
*/
private byte[] ref(final boolean f) throws IOException {
// scans numeric entities
if (consume('#')) { // [66]
final TokenBuilder ent = new TokenBuilder();
int b = 10;
int ch = nextChar();
ent.add(ch);
if (ch == 'x') {
b = 16;
ent.add(ch = nextChar());
}
int n = 0;
do {
final boolean m = ch >= '0' && ch <= '9';
final boolean h = b == 16 && (ch >= 'a' && ch <= 'f' || ch >= 'A' && ch <= 'F');
if (!m && !h) {
completeRef(ent);
return QUESTION;
}
n *= b;
n += ch & 15;
if (!m) n += 9;
ent.add(ch = nextChar());
} while (ch != ';');
if (!valid(n)) return QUESTION;
ent.reset();
ent.add(n);
return ent.finish();
}
// scans predefined entities [68]
final byte[] name = name(false);
if (!consume(';')) return QUESTION;
if (!f) return concat(AMPER, name, SEMI);
byte[] en = ents.get(name);
if (en == null) {
// unknown entity: try HTML entities (lazy initialization)
if (HTMLENTS.size() == 0) {
for (int s = 0; s < HTMLENTITIES.length; s += 2) {
HTMLENTS.add(token(HTMLENTITIES[s]), token(HTMLENTITIES[s + 1]));
}
}
en = HTMLENTS.get(name);
}
return en == null ? QUESTION : en;
}
/**
* Reads next character or throws an exception if all bytes have been read.
*
* @return next character
* @throws IOException I/O exception
*/
private int consume() throws IOException {
while (true) {
final int ch = input.read();
if (ch == -1) return 0;
if (ch == '%' && pe) { // [69]
final byte[] key = name(true);
final byte[] val = pents.get(key);
if (val == null) error(UNKNOWNPE, key);
check(';');
input.add(val, true);
} else {
return ch;
}
}
}