/**
* With the start token expected to be the first token of a selector group, create and issue the
* group, then invoke handleDeclarationBlock. At exit the last token returned from the iterator is
* expected to be '}'.
*/
private void handleRuleSet(
CssToken start, final CssTokenIterator iter, final CssContentHandler doc, CssErrorHandler err)
throws CssException {
char errChar = '{';
try {
List<CssSelector> selectors = handleSelectors(start, iter, err);
errChar = '}';
if (selectors == null) {
// handleSelectors() has issued errors, we forward
iter.next(MATCH_CLOSEBRACE);
return;
}
if (debug) {
checkState(iter.last.getChar() == '{');
checkState(!selectors.isEmpty());
}
doc.selectors(selectors);
handleDeclarationBlock(iter.next(), iter, doc, err);
doc.endSelectors(selectors);
} catch (NoSuchElementException nse) {
err.error(
new CssGrammarException(GRAMMAR_PREMATURE_EOF, iter.last.location, "'" + errChar + "'"));
throw new PrematureEOFException();
}
if (debug) {
checkState(iter.last.getChar() == '}');
}
}
/**
* With start inparam being the first significant token in a selector, build the selector group
* (aka comma separated selectors), expected return when iter.last is '{'. On error, issue to
* errorlistener, and return (caller will forward).
*
* @return A syntactically valid CssSelector list, or null if fail.
* @throws CssException
*/
private List<CssSelector> handleSelectors(
CssToken start, CssTokenIterator iter, CssErrorHandler err) throws CssException {
List<CssSelector> selectors = Lists.newArrayList();
boolean end = false;
while (true) { // comma loop
CssSelector selector = new CssSelector(start.location);
while (true) { // combinator loop
CssSimpleSelectorSequence seq =
CssSelectorConstructFactory.createSimpleSelectorSequence(start, iter, err);
if (seq == null) {
// errors already issued
return null;
}
selector.components.add(seq);
int idx = iter.index();
start = iter.next();
if (MATCH_OPENBRACE.apply(start)) {
end = true;
break;
}
if (MATCH_COMMA.apply(start)) {
break;
}
CssSelectorCombinator comb = CssSelectorConstructFactory.createCombinator(start, iter, err);
if (comb != null) {
selector.components.add(comb);
start = iter.next();
} else if (iter.list.get(idx + 1).type == CssToken.Type.S) {
selector.components.add(new CssSelectorCombinator(' ', start.location));
} else {
err.error(
new CssGrammarException(
GRAMMAR_UNEXPECTED_TOKEN, iter.last.location, iter.last.chars));
return null;
}
} // combinator loop
selectors.add(selector);
if (end) {
break;
}
if (debug) {
checkState(MATCH_COMMA.apply(start));
}
start = iter.next();
} // comma loop
return selectors;
}
/**
* Append property value components to declaration.value, return false if fail with iter.last at
* the the token which caused the fail.
*/
private boolean handlePropertyValue(
CssDeclaration declaration, CssToken start, CssTokenIterator iter, boolean isStyleAttribute) {
// we dont worry about EOF here, throw to caller
while (true) {
if (start.type == CssToken.Type.IMPORTANT) {
declaration.important = true;
} else {
CssConstruct cc =
CssConstructFactory.create(
start, iter, MATCH_SEMI_CLOSEBRACE, ContextRestrictions.PROPERTY_VALUE);
if (cc == null) {
return false;
} else {
declaration.components.add(cc);
}
}
// if isStyleAttribute, then parse as declaration-list grammar,
// i.e. no braces
if ((isStyleAttribute && !iter.hasNext())
|| (MATCH_SEMI.apply(iter.peek()))
|| (!isStyleAttribute && MATCH_CLOSEBRACE.apply(iter.peek()))) {
return declaration.components.size() > 0;
} else {
start = iter.next();
}
}
}
/** Parse a CSS style attribute. */
public void parseStyleAttribute(
final Reader reader, String systemID, final CssErrorHandler err, final CssContentHandler doc)
throws IOException, CssException {
CssTokenIterator iter = scan(reader, systemID, err);
doc.startDocument();
while (iter.hasNext()) {
CssToken tk = iter.next();
if (MATCH_SEMI.apply(tk)) {
continue; // starting with ';' is allowed, Issue 238
}
try {
CssDeclaration decl = handleDeclaration(tk, iter, doc, err, true);
if (decl != null) {
doc.declaration(decl);
} else {
// #handleDeclaration has issued errors
return;
}
} catch (PrematureEOFException te) {
// The subroutines report premature EOF to ErrHandler
// on occurrence; if the listener rethrows it will
// be a CssException so we don't catch it here.
break;
}
}
doc.endDocument();
}
/**
* With start token being the first non-ignorable token inside the declaration block, iterate
* issuing CssDeclaration objects until the block ends.
*/
private void handleDeclarationBlock(
CssToken start, CssTokenIterator iter, final CssContentHandler doc, CssErrorHandler err)
throws CssException {
while (true) {
if (MATCH_CLOSEBRACE.apply(start)) {
return;
}
CssDeclaration decl = handleDeclaration(start, iter, doc, err, false);
try {
if (decl != null) {
doc.declaration(decl);
if (debug) {
checkState(MATCH_SEMI_CLOSEBRACE.apply(iter.last));
}
// continue or return: we may be at "; next decl" or "}" or ";}"
if (MATCH_CLOSEBRACE.apply(iter.last)) {
return;
} else if (MATCH_SEMI.apply(iter.last) && MATCH_CLOSEBRACE.apply(iter.peek())) {
iter.next();
return;
} else {
if (debug) {
checkState(MATCH_SEMI.apply(iter.last));
}
// we have ';', expect another decl
start = iter.next(); // first token after ';'
}
} else {
// #handleDeclaration returned null to signal error
// #handleDeclaration has issued errors, we forward
start = iter.next(MATCH_SEMI_CLOSEBRACE);
if (MATCH_SEMI.apply(start)) {
start = iter.next();
}
}
} catch (NoSuchElementException nse) {
err.error(
new CssGrammarException(
GRAMMAR_PREMATURE_EOF, iter.last.location, "';' " + Messages.get("or") + " '}'"));
throw new PrematureEOFException();
}
}
}
/** Parse a CSS document. */
public void parse(
final Reader reader,
final String systemID,
final CssErrorHandler err,
final CssContentHandler doc)
throws IOException, CssException {
CssTokenIterator iter = scan(reader, systemID, err);
doc.startDocument();
while (iter.hasNext(FILTER_S_CMNT_CDO_CDC)) {
CssToken tk = iter.next(FILTER_S_CMNT_CDO_CDC);
try {
if (tk.type == CssToken.Type.ATKEYWORD) {
handleAtRule(tk, iter, doc, err);
if (debug) {
checkArgument(MATCH_SEMI_CLOSEBRACE.apply(iter.last));
}
} else {
handleRuleSet(tk, iter, doc, err);
if (debug) {
checkArgument(MATCH_CLOSEBRACE.apply(iter.last));
}
}
} catch (PrematureEOFException te) {
// The subroutines report premature EOF to ErrHandler
// on occurrence; if the listener rethrows it will
// be a CssException so we don't catch it here.
break;
}
}
doc.endDocument();
}
/**
* With start token required to be an ATKEYWORD, collect at-rule parameters if any, and if the
* at-rule has a block, invoke those handlers.
*/
private void handleAtRule(
CssToken start, CssTokenIterator iter, CssContentHandler doc, CssErrorHandler err)
throws CssException {
if (debug) {
checkArgument(start.type == CssToken.Type.ATKEYWORD);
checkArgument(iter.index() == iter.list.indexOf(start));
checkArgument(iter.filter() == FILTER_S_CMNT);
}
CssAtRule atRule = new CssAtRule(start.getChars(), start.location);
CssToken tk;
try {
while (true) {
tk = iter.next();
if (MATCH_SEMI_OPENBRACE.apply(tk)) {
// ';' or '{', expected end
atRule.hasBlock = tk.getChar() == '{';
break;
} else {
CssConstruct param = handleAtRuleParam(tk, iter, doc, err);
if (param == null) {
// issue error, forward, then return
err.error(
new CssGrammarException(
GRAMMAR_UNEXPECTED_TOKEN, iter.last.location, iter.last.chars));
// skip to atrule closebrace, ignoring any inner blocks
int stack = 0;
while (true) {
CssToken tok = iter.next();
if (MATCH_SEMI.apply(tok) && stack == 0) {
return; // a non-block at rule
} else if (MATCH_OPENBRACE.apply(tok)) {
stack++;
} else if (MATCH_CLOSEBRACE.apply(tok)) {
if (stack == 1) {
break;
}
stack--;
}
}
return;
} else {
atRule.components.add(param);
}
}
}
} catch (NoSuchElementException nse) {
// UAs required to close any open constructs on premature EOF
doc.startAtRule(atRule);
err.error(
new CssGrammarException(
GRAMMAR_PREMATURE_EOF, iter.last.location, "';' " + Messages.get("or") + " '{'"));
doc.endAtRule(atRule.getName().get());
throw new PrematureEOFException();
}
if (debug) {
checkArgument(MATCH_SEMI_OPENBRACE.apply(iter.last));
checkArgument(iter.filter() == FILTER_S_CMNT);
}
// ending up here only on expected end
doc.startAtRule(atRule);
if (atRule.hasBlock) {
try {
if (hasRuleSet(atRule, iter)) {
while (!MATCH_CLOSEBRACE.apply(iter.next())) {
if (iter.last.type == CssToken.Type.ATKEYWORD) {
handleAtRule(iter.last, iter, doc, err);
} else {
handleRuleSet(iter.last, iter, doc, err);
}
}
} else {
handleDeclarationBlock(iter.next(), iter, doc, err);
}
} catch (NoSuchElementException nse) {
err.error(new CssGrammarException(GRAMMAR_PREMATURE_EOF, iter.last.location, "'}'"));
doc.endAtRule(atRule.name.get());
throw new PrematureEOFException();
}
}
doc.endAtRule(atRule.name.get());
}
/**
* With start expected to be an IDENT token representing the property name, build the declaration
* and return after hitting ';' or '}'. On error, issue to errhandler, return null, caller
* forwards.
*/
private CssDeclaration handleDeclaration(
CssToken name,
CssTokenIterator iter,
CssContentHandler doc,
CssErrorHandler err,
boolean isStyleAttribute)
throws CssException {
if (name.type != CssToken.Type.IDENT) {
err.error(
new CssGrammarException(
GRAMMAR_EXPECTING_TOKEN,
name.location,
name.getChars(),
Messages.get("a_property_name")));
return null;
}
CssDeclaration declaration = new CssDeclaration(name.getChars(), name.location);
try {
if (!MATCH_COLON.apply(iter.next())) {
err.error(
new CssGrammarException(
GRAMMAR_EXPECTING_TOKEN, name.location, iter.last.getChars(), ":"));
return null;
}
} catch (NoSuchElementException nse) {
err.error(new CssGrammarException(GRAMMAR_PREMATURE_EOF, iter.last.location, ":"));
throw new PrematureEOFException();
}
try {
while (true) {
CssToken value = iter.next();
if (MATCH_SEMI_CLOSEBRACE.apply(value)) {
if (declaration.components.size() < 1) {
err.error(
new CssGrammarException(
GRAMMAR_EXPECTING_TOKEN,
iter.last.location,
value.getChar(),
Messages.get("a_property_value")));
return null;
} else {
return declaration;
}
} else {
if (!handlePropertyValue(declaration, value, iter, isStyleAttribute)) {
err.error(
new CssGrammarException(
GRAMMAR_UNEXPECTED_TOKEN, iter.last.location, iter.last.getChars()));
return null;
} else {
if (isStyleAttribute && !iter.hasNext()) {
return declaration;
}
}
}
}
} catch (NoSuchElementException nse) {
err.error(
new CssGrammarException(
GRAMMAR_PREMATURE_EOF, iter.last.location, "';' " + Messages.get("or") + " '}'"));
throw new PrematureEOFException();
}
}