public State step(State... nextStates) throws ParseException {
Event newEvent = cursor.next();
if (state.isPop(getId(newEvent))) {
state = stateStack.pop();
next = eventStack.pop();
return state;
} else {
for (State s : nextStates) {
if (s.allowedTransitions.contains(getId(newEvent))) {
if (state != State.EMPTY && !next.is(Event.ID.Scalar)) {
eventStack.push(next);
stateStack.push(state);
}
next = newEvent;
state = s;
return state;
}
}
}
throw new ParseException("invalid state", next);
}
@JRubyMethod
public IRubyObject parse(ThreadContext context, IRubyObject target) {
Ruby runtime = context.runtime;
// FIXME? only supports Unicode, since we have to produces strings...
StreamReader reader;
if (target.respondsTo("read")) {
reader = new StreamReader(new InputStreamReader(new IOInputStream(target)));
} else {
reader = new StreamReader(new StringReader(target.convertToString().asJavaString()));
}
Parser parser = new ParserImpl(reader);
IRubyObject handler = getInstanceVariable("@handler");
Event event;
while (true) {
try {
event = parser.getEvent();
// FIXME: Event should expose a getID, so it can be switched
if (event.is(ID.StreamStart)) {
invoke(context, handler, "start_stream", runtime.newFixnum(YAML_ANY_ENCODING));
} else if (event.is(ID.DocumentStart)) {
DocumentStartEvent dse = (DocumentStartEvent) event;
Integer[] versionInts = dse.getVersion();
IRubyObject version =
versionInts == null
? runtime.getNil()
: RubyArray.newArray(
runtime,
runtime.newFixnum(versionInts[0]),
runtime.newFixnum(versionInts[1]));
Map<String, String> tagsMap = dse.getTags();
RubyArray tags = RubyArray.newArray(runtime);
if (tags.size() > 0) {
for (Map.Entry<String, String> tag : tagsMap.entrySet()) {
tags.append(
RubyArray.newArray(
runtime,
RubyString.newString(runtime, tag.getKey()),
RubyString.newString(runtime, tag.getValue())));
}
}
invoke(
context,
handler,
"start_document",
version,
tags,
runtime.newBoolean(dse.getExplicit()));
} else if (event.is(ID.DocumentEnd)) {
DocumentEndEvent dee = (DocumentEndEvent) event;
invoke(context, handler, "end_document", runtime.newBoolean(dee.getExplicit()));
} else if (event.is(ID.Alias)) {
AliasEvent ae = (AliasEvent) event;
IRubyObject alias = runtime.getNil();
if (ae.getAnchor() != null) {
alias = RubyString.newString(runtime, ae.getAnchor());
}
invoke(context, handler, "alias", alias);
} else if (event.is(ID.Scalar)) {
ScalarEvent se = (ScalarEvent) event;
IRubyObject anchor =
se.getAnchor() == null
? runtime.getNil()
: RubyString.newString(runtime, se.getAnchor());
IRubyObject tag =
se.getTag() == null ? runtime.getNil() : RubyString.newString(runtime, se.getTag());
IRubyObject plain_implicit = runtime.newBoolean(se.getImplicit().isFirst());
IRubyObject quoted_implicit = runtime.newBoolean(se.getImplicit().isSecond());
IRubyObject style = runtime.newFixnum(se.getStyle());
IRubyObject val = RubyString.newString(runtime, se.getValue());
invoke(
context, handler, "scalar", val, anchor, tag, plain_implicit, quoted_implicit, style);
} else if (event.is(ID.SequenceStart)) {
SequenceStartEvent sse = (SequenceStartEvent) event;
IRubyObject anchor =
sse.getAnchor() == null
? runtime.getNil()
: RubyString.newString(runtime, sse.getAnchor());
IRubyObject tag =
sse.getTag() == null ? runtime.getNil() : RubyString.newString(runtime, sse.getTag());
IRubyObject implicit = runtime.newBoolean(sse.getImplicit());
IRubyObject style = runtime.newFixnum(sse.getFlowStyle() ? 1 : 0);
invoke(context, handler, "start_sequence", anchor, tag, implicit, style);
} else if (event.is(ID.SequenceEnd)) {
invoke(context, handler, "end_sequence");
} else if (event.is(ID.MappingStart)) {
MappingStartEvent mse = (MappingStartEvent) event;
IRubyObject anchor =
mse.getAnchor() == null
? runtime.getNil()
: RubyString.newString(runtime, mse.getAnchor());
IRubyObject tag =
mse.getTag() == null ? runtime.getNil() : RubyString.newString(runtime, mse.getTag());
IRubyObject implicit = runtime.newBoolean(mse.getImplicit());
IRubyObject style = runtime.newFixnum(mse.getFlowStyle() ? 1 : 0);
invoke(context, handler, "start_mapping", anchor, tag, implicit, style);
} else if (event.is(ID.MappingEnd)) {
invoke(context, handler, "end_mapping");
} else if (event.is(ID.StreamEnd)) {
invoke(context, handler, "end_stream");
break;
}
} catch (ParserException pe) {
parser = null;
RubyKernel.raise(
context,
runtime.getModule("Psych").getConstant("SyntaxError"),
new IRubyObject[] {runtime.newString(pe.getLocalizedMessage())},
Block.NULL_BLOCK);
}
}
return this;
}
public String getValue() throws ParseException {
if (next.is(ID.Scalar)) {
return ((ScalarEvent) next).getValue();
}
throw new ParseException("not a scalar", next);
}
private Event.ID getId(Event e) throws ParseException {
for (Event.ID i : Event.ID.values()) {
if (e.is(i)) return i;
}
throw new ParseException("unreachable code", next);
}