public final void nextToken()

in core/src/main/java/com/alibaba/druid/sql/parser/Lexer.java [1252:1520]

• 252 lines of code
• 98 McCabe index (conditional complexity)

    public final void nextToken() {
        startPos = pos;
        bufPos = 0;
        if (comments != null && comments.size() > 0) {
            comments = null;
        }

        this.lines = 0;
        int startLine = line;

        for (; ; ) {
            if (isWhitespace(ch)) {
                if (ch == '\n') {
                    line++;

                    lines = line - startLine;
                }

                ch = charAt(++pos);
                startPos = pos;
                continue;
            }

            if (ch == EOI && pos < text.length()) {
                ch = charAt(++pos);
                continue;
            }

            if (ch == '$') {
                scanVariable();
                return;
            }

            if (isFirstIdentifierChar(ch)) {
                if (ch == '（') {
                    scanChar();
                    token = LPAREN;
                    return;
                } else if (ch == '）') {
                    scanChar();
                    token = RPAREN;
                    return;
                }

                if (ch == 'N' || ch == 'n') {
                    if (charAt(pos + 1) == '\'') {
                        ++pos;
                        ch = '\'';
                        scanString();
                        token = Token.LITERAL_NCHARS;
                        return;
                    }
                }

                if (ch == '—' && charAt(pos + 1) == '—' && charAt(pos + 2) == '\n') {
                    pos += 3;
                    ch = charAt(pos);
                    continue;
                }

                scanIdentifier();
                return;
            }

            switch (ch) {
                case '0':
                    if (charAt(pos + 1) == 'x') {
                        scanChar();
                        scanChar();
                        scanHexaDecimal();
                    } else {
                        scanNumber();
                    }
                    return;
                case '1':
                case '2':
                case '3':
                case '4':
                case '5':
                case '6':
                case '7':
                case '8':
                case '9':
                    scanNumber();
                    return;
                case ',':
                case '，':
                    scanChar();
                    token = COMMA;
                    return;
                case '(':
                case '（':
                    scanChar();
                    token = LPAREN;
                    return;
                case ')':
                case '）':
                    scanChar();
                    token = RPAREN;
                    return;
                case '[':
                    scanLBracket();
                    return;
                case ']':
                    scanChar();
                    token = RBRACKET;
                    return;
                case '{':
                    scanChar();
                    token = LBRACE;
                    return;
                case '}':
                    scanChar();
                    token = RBRACE;
                    return;
                case ':':
                    scanChar();
                    if (ch == '=') {
                        scanChar();
                        token = COLONEQ;
                    } else if (ch == ':') {
                        scanChar();
                        token = COLONCOLON;
                    } else {
                        if (isEnabled(SQLParserFeature.TDDLHint) || dialectFeatureEnabled(NextTokenColon)) {
                            token = COLON;
                            return;
                        }
                        unscan();
                        scanVariable();
                    }
                    return;
                case '#':
                    scanSharp();
                    if ((token == Token.LINE_COMMENT || token == Token.MULTI_LINE_COMMENT) && skipComment) {
                        bufPos = 0;
                        continue;
                    }
                    return;
                case '.':
                    scanChar();
                    if (isDigit(ch)
                            && (pos == 1 || token != IDENTIFIER)
                    ) {
                        unscan();
                        scanNumber();
                        return;
                    } else if (ch == '.') {
                        scanChar();
                        if (ch == '.') {
                            scanChar();
                            token = Token.DOTDOTDOT;
                        } else {
                            token = Token.DOTDOT;
                        }
                    } else {
                        token = Token.DOT;
                    }
                    return;
                case '\'':
                    scanString();
                    return;
                case '\"':
                    scanAlias();
                    return;
                case '*':
                    scanChar();
                    token = Token.STAR;
                    return;
                case '?':
                    scanChar();
                    nextTokenQues();
                    return;
                case ';':
                    scanChar();
                    token = Token.SEMI;
                    return;
                case '`':
                    throw new ParserException("TODO. " + info()); // TODO
                case '@':
                    scanVariable_at();
                    return;
                case '-':
                    char next = charAt(pos + 1);
                    if (next == '-') {
                        scanComment();
                        if ((token == Token.LINE_COMMENT || token == Token.MULTI_LINE_COMMENT) && skipComment) {
                            bufPos = 0;
                            continue;
                        }
                    } else if (next >= '0' && next <= '9') {
                        if (token == null) {
                            scanNumber();
                            return;
                        }
                        switch (token) {
                            case COMMA:
                            case LPAREN:
                            case WITH:
                            case BY:
                                scanNumber();
                                break;
                            default:
                                scanOperator();
                                break;
                        }
                    } else {
                        scanOperator();
                    }
                    return;
                case '/':
                    char nextChar = charAt(pos + 1);
                    if (nextChar == '/'
                            || nextChar == '*'
                            || (nextChar == '!' && isEnabled(SQLParserFeature.TDDLHint))) {
                        scanComment();
                        if ((token == Token.LINE_COMMENT || token == Token.MULTI_LINE_COMMENT) && skipComment) {
                            bufPos = 0;
                            continue;
                        }
                    } else if (nextChar == ' ' && charAt(pos + 2) == '*') {
                        scanComment();
                        if ((token == Token.LINE_COMMENT || token == Token.MULTI_LINE_COMMENT) && skipComment) {
                            bufPos = 0;
                            continue;
                        }
                    } else if (nextChar == ' ' && charAt(pos + 2) == ' ' && charAt(pos + 3) == '*') {
                        scanComment();
                        if ((token == Token.LINE_COMMENT || token == Token.MULTI_LINE_COMMENT) && skipComment) {
                            bufPos = 0;
                            continue;
                        }
                    } else {
                        token = Token.SLASH;
                        scanChar();
                    }
                    return;
                default:
                    if (Character.isLetter(ch)) {
                        scanIdentifier();
                        return;
                    }

                    if (isOperator(ch)) {
                        scanOperator();
                        return;
                    }

                    if (ch == '\\' && charAt(pos + 1) == 'N'
                            && dialectFeatureEnabled(NextTokenPrefixN)) {
                        scanChar();
                        scanChar();
                        token = Token.NULL;
                        return;
                    }

                    // QS_TODO ?
                    if (isEOF()) { // JLS
                        token = EOF;
                    } else {
                        lexError("illegal.char", String.valueOf((int) ch));
                        scanChar();
                    }

                    return;
            }
        }

    }