import org.yaml.snakeyaml.error.Mark; //导入依赖的package包/类
public Event produce() {
    // Parse the document end.
    Token token = scanner.peekToken();
    Mark startMark = token.getStartMark();
    Mark endMark = startMark;
    boolean explicit = false;
    if (scanner.checkToken(Token.ID.DocumentEnd)) {
        token = scanner.getToken();
        endMark = token.getEndMark();
        explicit = true;
    }
    Event event = new DocumentEndEvent(startMark, endMark, explicit);
    // Prepare the next state.
    state = new ParseDocumentStart();
    return event;
}
 

import org.yaml.snakeyaml.error.Mark; //导入依赖的package包/类
private void fetchStreamEnd() {
    // Set the current intendation to -1.
    unwindIndent(-1);

    // Reset simple keys.
    removePossibleSimpleKey();
    this.allowSimpleKey = false;
    this.possibleSimpleKeys.clear();

    // Read the token.
    Mark mark = reader.getMark();

    // Add STREAM-END.
    Token token = new StreamEndToken(mark, mark);
    this.tokens.add(token);

    // The stream is finished.
    this.done = true;
}
 

import org.yaml.snakeyaml.error.Mark; //导入依赖的package包/类
private String scanDirectiveIgnoredLine(Mark startMark) {
    // See the specification for details.
    while (reader.peek() == ' ') {
        reader.forward();
    }
    if (reader.peek() == '#') {
        while (Constant.NULL_OR_LINEBR.hasNo(reader.peek())) {
            reader.forward();
        }
    }
    int c = reader.peek();
    String lineBreak = scanLineBreak();
    if (lineBreak.length() == 0 && c != '\0') {
        final String s = String.valueOf(Character.toChars(c));
        throw new ScannerException("while scanning a directive", startMark,
                "expected a comment or a line break, but found " + s + "(" + c + ")",
                reader.getMark());
    }
    return lineBreak;
}
 

import org.yaml.snakeyaml.error.Mark; //导入依赖的package包/类
/**
 * <p>
 * Read a %TAG directive value:
 * 
 * <pre>
 * s-ignored-space+ c-tag-handle s-ignored-space+ ns-tag-prefix s-l-comments
 * </pre>
 * 
 * </p>
 * 
 * @see <a href="http://www.yaml.org/spec/1.1/#id896044"></a>
 */
private List<String> scanTagDirectiveValue(Mark startMark) {
    // See the specification for details.
    while (reader.peek() == ' ') {
        reader.forward();
    }
    String handle = scanTagDirectiveHandle(startMark);
    while (reader.peek() == ' ') {
        reader.forward();
    }
    String prefix = scanTagDirectivePrefix(startMark);
    List<String> result = new ArrayList<String>(2);
    result.add(handle);
    result.add(prefix);
    return result;
}
 

import org.yaml.snakeyaml.error.Mark; //导入依赖的package包/类
private String scanFlowScalarBreaks(Mark startMark) {
    // See the specification for details.
    StringBuilder chunks = new StringBuilder();
    while (true) {
        // Instead of checking indentation, we check for document
        // separators.
        String prefix = reader.prefix(3);
        if (("---".equals(prefix) || "...".equals(prefix))
                && Constant.NULL_BL_T_LINEBR.has(reader.peek(3))) {
            throw new ScannerException("while scanning a quoted scalar", startMark,
                    "found unexpected document separator", reader.getMark());
        }
        // Scan past any number of spaces and tabs, ignoring them
        while (" \t".indexOf(reader.peek()) != -1) {
            reader.forward();
        }
        // If we stopped at a line break, add that; otherwise, return the
        // assembled set of scalar breaks.
        String lineBreak = scanLineBreak();
        if (lineBreak.length() != 0) {
            chunks.append(lineBreak);
        } else {
            return chunks.toString();
        }
    }
}
 

import org.yaml.snakeyaml.error.Mark; //导入依赖的package包/类
public ParserImpl(Scanner scanner) {
    this.scanner = scanner;
    currentEvent = null;
    directives = new VersionTagsTuple(null, new HashMap<String, String>(DEFAULT_TAGS));
    states = new ArrayStack<Production>(100);
    marks = new ArrayStack<Mark>(10);
    state = new ParseStreamStart();
}
 

import org.yaml.snakeyaml.error.Mark; //导入依赖的package包/类
public DirectiveToken(String name, List<T> value, Mark startMark, Mark endMark) {
    super(startMark, endMark);
    this.name = name;
    if (value != null && value.size() != 2) {
        throw new YAMLException("Two strings must be provided instead of "
                + String.valueOf(value.size()));
    }
    this.value = value;
}
 

import org.yaml.snakeyaml.error.Mark; //导入依赖的package包/类
public SequenceNode(Tag tag, boolean resolved, List<Node> value, Mark startMark, Mark endMark,
        Boolean flowStyle) {
    super(tag, startMark, endMark, flowStyle);
    if (value == null) {
        throw new NullPointerException("value in a Node is required.");
    }
    this.value = value;
    this.resolved = resolved;
}
 

import org.yaml.snakeyaml.error.Mark; //导入依赖的package包/类
public ScalarNode(Tag tag, boolean resolved, String value, Mark startMark, Mark endMark,
        Character style) {
    super(tag, startMark, endMark);
    if (value == null) {
        throw new NullPointerException("value in a Node is required.");
    }
    this.value = value;
    this.style = style;
    this.resolved = resolved;
}
 

import org.yaml.snakeyaml.error.Mark; //导入依赖的package包/类
public Node(Tag tag, Mark startMark, Mark endMark) {
    setTag(tag);
    this.startMark = startMark;
    this.endMark = endMark;
    this.type = Object.class;
    this.twoStepsConstruction = false;
    this.resolved = true;
    this.useClassConstructor = null;
}
 

import org.yaml.snakeyaml.error.Mark; //导入依赖的package包/类
public MappingNode(Tag tag, boolean resolved, List<NodeTuple> value, Mark startMark,
        Mark endMark, Boolean flowStyle) {
    super(tag, startMark, endMark, flowStyle);
    if (value == null) {
        throw new NullPointerException("value in a Node is required.");
    }
    this.value = value;
    this.resolved = resolved;
}
 

import org.yaml.snakeyaml.error.Mark; //导入依赖的package包/类
public DocumentStartEvent(Mark startMark, Mark endMark, boolean explicit, Version version,
        Map<String, String> tags) {
    super(startMark, endMark);
    this.explicit = explicit;
    this.version = version;
    // TODO enforce not null
    // if (tags == null) {
    // throw new NullPointerException("Tags must be provided.");
    // }
    this.tags = tags;
}
 

import org.yaml.snakeyaml.error.Mark; //导入依赖的package包/类
/**
 * Fetch an entry in the block style.
 * 
 * @see <a href="http://www.yaml.org/spec/1.1/#id863975"></a>
 */
private void fetchBlockEntry() {
    // Block context needs additional checks.
    if (this.flowLevel == 0) {
        // Are we allowed to start a new entry?
        if (!this.allowSimpleKey) {
            throw new ScannerException(null, null, "sequence entries are not allowed here",
                    reader.getMark());
        }

        // We may need to add BLOCK-SEQUENCE-START.
        if (addIndent(this.reader.getColumn())) {
            Mark mark = reader.getMark();
            this.tokens.add(new BlockSequenceStartToken(mark, mark));
        }
    } else {
        // It's an error for the block entry to occur in the flow
        // context,but we let the parser detect this.
    }
    // Simple keys are allowed after '-'.
    this.allowSimpleKey = true;

    // Reset possible simple key on the current level.
    removePossibleSimpleKey();

    // Add BLOCK-ENTRY.
    Mark startMark = reader.getMark();
    reader.forward();
    Mark endMark = reader.getMark();
    Token token = new BlockEntryToken(startMark, endMark);
    this.tokens.add(token);
}
 

import org.yaml.snakeyaml.error.Mark; //导入依赖的package包/类
/**
 * Fetch a key in a block-style mapping.
 * 
 * @see <a href="http://www.yaml.org/spec/1.1/#id863975"></a>
 */
private void fetchKey() {
    // Block context needs additional checks.
    if (this.flowLevel == 0) {
        // Are we allowed to start a key (not necessary a simple)?
        if (!this.allowSimpleKey) {
            throw new ScannerException(null, null, "mapping keys are not allowed here",
                    reader.getMark());
        }
        // We may need to add BLOCK-MAPPING-START.
        if (addIndent(this.reader.getColumn())) {
            Mark mark = reader.getMark();
            this.tokens.add(new BlockMappingStartToken(mark, mark));
        }
    }
    // Simple keys are allowed after '?' in the block context.
    this.allowSimpleKey = this.flowLevel == 0;

    // Reset possible simple key on the current level.
    removePossibleSimpleKey();

    // Add KEY.
    Mark startMark = reader.getMark();
    reader.forward();
    Mark endMark = reader.getMark();
    Token token = new KeyToken(startMark, endMark);
    this.tokens.add(token);
}
 

import org.yaml.snakeyaml.error.Mark; //导入依赖的package包/类
public CollectionStartEvent(String anchor, String tag, boolean implicit, Mark startMark,
        Mark endMark, Boolean flowStyle) {
    super(anchor, startMark, endMark);
    this.tag = tag;
    this.implicit = implicit;
    this.flowStyle = flowStyle;
}
 

import org.yaml.snakeyaml.error.Mark; //导入依赖的package包/类
public SimpleKey(int tokenNumber, boolean required, int index, int line, int column, Mark mark) {
    this.tokenNumber = tokenNumber;
    this.required = required;
    this.index = index;
    this.line = line;
    this.column = column;
    this.mark = mark;
}
 

import org.yaml.snakeyaml.error.Mark; //导入依赖的package包/类
/**
 * Fetch an entry in the flow style. Flow-style entries occur either
 * immediately after the start of a collection, or else after a comma.
 * 
 * @see <a href="http://www.yaml.org/spec/1.1/#id863975"></a>
 */
private void fetchFlowEntry() {
    // Simple keys are allowed after ','.
    this.allowSimpleKey = true;

    // Reset possible simple key on the current level.
    removePossibleSimpleKey();

    // Add FLOW-ENTRY.
    Mark startMark = reader.getMark();
    reader.forward();
    Mark endMark = reader.getMark();
    Token token = new FlowEntryToken(startMark, endMark);
    this.tokens.add(token);
}
 

import org.yaml.snakeyaml.error.Mark; //导入依赖的package包/类
/**
 * <p>
 * Scan a sequence of %-escaped URI escape codes and convert them into a
 * String representing the unescaped values.
 * </p>
 * 
 * FIXME This method fails for more than 256 bytes' worth of URI-encoded
 * characters in a row. Is this possible? Is this a use-case?
 * 
 * @see <a href="http://www.ietf.org/rfc/rfc2396.txt"></a>, section 2.4, Escaped Encoding.
 */
private String scanUriEscapes(String name, Mark startMark) {
    // First, look ahead to see how many URI-escaped characters we should
    // expect, so we can use the correct buffer size.
    int length = 1;
    while (reader.peek(length * 3) == '%') {
        length++;
    }
    // See the specification for details.
    // URIs containing 16 and 32 bit Unicode characters are
    // encoded in UTF-8, and then each octet is written as a
    // separate character.
    Mark beginningMark = reader.getMark();
    ByteBuffer buff = ByteBuffer.allocate(length);
    while (reader.peek() == '%') {
        reader.forward();
        try {
            byte code = (byte) Integer.parseInt(reader.prefix(2), 16);
            buff.put(code);
        } catch (NumberFormatException nfe) {
            int c1 = reader.peek();
            final String s1 = String.valueOf(Character.toChars(c1));
            int c2 = reader.peek(1);
            final String s2 = String.valueOf(Character.toChars(c2));
            throw new ScannerException("while scanning a " + name, startMark,
                    "expected URI escape sequence of 2 hexadecimal numbers, but found "
                            + s1 + "(" + c1 + ") and "
                            + s2 + "(" + c2 + ")",
                    reader.getMark());
        }
        reader.forward(2);
    }
    buff.flip();
    try {
        return UriEncoder.decode(buff);
    } catch (CharacterCodingException e) {
        throw new ScannerException("while scanning a " + name, startMark,
                "expected URI in UTF-8: " + e.getMessage(), beginningMark);
    }
}
 

import org.yaml.snakeyaml.error.Mark; //导入依赖的package包/类
public ScalarEvent(String anchor, String tag, ImplicitTuple implicit, String value,
        Mark startMark, Mark endMark, Character style) {
    super(anchor, startMark, endMark);
    this.tag = tag;
    this.implicit = implicit;
    this.value = value;
    this.style = style;
}
 

import org.yaml.snakeyaml.error.Mark; //导入依赖的package包/类
/**
 * We always add STREAM-START as the first token and STREAM-END as the last
 * token.
 */
private void fetchStreamStart() {
    // Read the token.
    Mark mark = reader.getMark();

    // Add STREAM-START.
    Token token = new StreamStartToken(mark, mark);
    this.tokens.add(token);
}