All Downloads are FREE. Search and download functionalities are using the official Maven repository.

org.bson.json.JsonScanner Maven / Gradle / Ivy

The newest version!
/*
 * Copyright 2008-present MongoDB, Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.bson.json;

import org.bson.BsonRegularExpression;
import java.io.Reader;

/**
 *  Parses the string representation of a JSON object into a set of {@link JsonToken}-derived objects.
 *
 *  @since 3.0
 *
 * @deprecated Usage of this API is not supported in AEM as a Cloud Service.
 */
@Deprecated(since = "2022-10-31")
class JsonScanner {

    private final JsonBuffer buffer;

    JsonScanner(final JsonBuffer buffer) {
        this.buffer = buffer;
    }

    JsonScanner(final String json) {
        this(new JsonStringBuffer(json));
    }

    JsonScanner(final Reader reader) {
        this(new JsonStreamBuffer(reader));
    }

    public void reset(final int markPos) {
        buffer.reset(markPos);
    }

    public int mark() {
        return buffer.mark();
    }

    public void discard(final int markPos) {
        buffer.discard(markPos);
    }

    /**
     * Finds and returns the next complete token from this scanner. If scanner reached the end of the source, it will return a token with
     * {@code JSONTokenType.END_OF_FILE} type.
     *
     * @return The next token.
     * @throws JsonParseException if source is invalid.
     */
    public JsonToken nextToken() {
        int c = buffer.read();
        while (c != -1 && Character.isWhitespace(c)) {
            c = buffer.read();
        }
        if (c == -1) {
            return new JsonToken(JsonTokenType.END_OF_FILE, "");
        }
        switch(c) {
            case '{':
                return new JsonToken(JsonTokenType.BEGIN_OBJECT, "{");
            case '}':
                return new JsonToken(JsonTokenType.END_OBJECT, "}");
            case '[':
                return new JsonToken(JsonTokenType.BEGIN_ARRAY, "[");
            case ']':
                return new JsonToken(JsonTokenType.END_ARRAY, "]");
            case '(':
                return new JsonToken(JsonTokenType.LEFT_PAREN, "(");
            case ')':
                return new JsonToken(JsonTokenType.RIGHT_PAREN, ")");
            case ':':
                return new JsonToken(JsonTokenType.COLON, ":");
            case ',':
                return new JsonToken(JsonTokenType.COMMA, ",");
            case '\'':
            case '"':
                return scanString((char) c);
            case '/':
                return scanRegularExpression();
            default:
                if (c == '-' || Character.isDigit(c)) {
                    return scanNumber((char) c);
                } else if (c == '$' || c == '_' || Character.isLetter(c)) {
                    return scanUnquotedString((char) c);
                } else {
                    int position = buffer.getPosition();
                    buffer.unread(c);
                    throw new JsonParseException("Invalid JSON input. Position: %d. Character: '%c'.", position, c);
                }
        }
    }

    /**
     * Reads {@code RegularExpressionToken} from source. The following variants of lexemes are possible:
     * 
     *  /pattern/
     *  /\(pattern\)/
     *  /pattern/ims
     * 
* Options can include 'i','m','x','s' * * @return The regular expression token. * @throws JsonParseException if regular expression representation is not valid. */ private JsonToken scanRegularExpression() { StringBuilder patternBuilder = new StringBuilder(); StringBuilder optionsBuilder = new StringBuilder(); RegularExpressionState state = RegularExpressionState.IN_PATTERN; while (true) { int c = buffer.read(); switch(state) { case IN_PATTERN: switch(c) { case -1: state = RegularExpressionState.INVALID; break; case '/': state = RegularExpressionState.IN_OPTIONS; break; case '\\': state = RegularExpressionState.IN_ESCAPE_SEQUENCE; break; default: state = RegularExpressionState.IN_PATTERN; break; } break; case IN_ESCAPE_SEQUENCE: state = RegularExpressionState.IN_PATTERN; break; case IN_OPTIONS: switch(c) { case 'i': case 'm': case 'x': case 's': state = RegularExpressionState.IN_OPTIONS; break; case ',': case '}': case ']': case ')': case -1: state = RegularExpressionState.DONE; break; default: if (Character.isWhitespace(c)) { state = RegularExpressionState.DONE; } else { state = RegularExpressionState.INVALID; } break; } break; default: break; } switch(state) { case DONE: buffer.unread(c); BsonRegularExpression regex = new BsonRegularExpression(patternBuilder.toString(), optionsBuilder.toString()); return new JsonToken(JsonTokenType.REGULAR_EXPRESSION, regex); case INVALID: throw new JsonParseException("Invalid JSON regular expression. Position: %d.", buffer.getPosition()); default: switch(state) { case IN_OPTIONS: if (c != '/') { optionsBuilder.append((char) c); } break; default: patternBuilder.append((char) c); break; } } } } /** * Reads {@code StringToken} from source. * * @return The string token. */ private JsonToken scanUnquotedString(final char firstChar) { StringBuilder sb = new StringBuilder(); sb.append(firstChar); int c = buffer.read(); while (c == '$' || c == '_' || Character.isLetterOrDigit(c)) { sb.append((char) c); c = buffer.read(); } buffer.unread(c); String lexeme = sb.toString(); return new JsonToken(JsonTokenType.UNQUOTED_STRING, lexeme); } /** * Reads number token from source. The following variants of lexemes are possible: *
     *  12
     *  123
     *  -0
     *  -345
     *  -0.0
     *  0e1
     *  0e-1
     *  -0e-1
     *  1e12
     *  -Infinity
     * 
* * @return The number token. * @throws JsonParseException if number representation is invalid. */ // CHECKSTYLE:OFF private JsonToken scanNumber(final char firstChar) { int c = firstChar; StringBuilder sb = new StringBuilder(); sb.append(firstChar); NumberState state; switch(c) { case '-': state = NumberState.SAW_LEADING_MINUS; break; case '0': state = NumberState.SAW_LEADING_ZERO; break; default: state = NumberState.SAW_INTEGER_DIGITS; break; } JsonTokenType type = JsonTokenType.INT64; while (true) { c = buffer.read(); switch(state) { case SAW_LEADING_MINUS: switch(c) { case '0': state = NumberState.SAW_LEADING_ZERO; break; case 'I': state = NumberState.SAW_MINUS_I; break; default: if (Character.isDigit(c)) { state = NumberState.SAW_INTEGER_DIGITS; } else { state = NumberState.INVALID; } break; } break; case SAW_LEADING_ZERO: switch(c) { case '.': state = NumberState.SAW_DECIMAL_POINT; break; case 'e': case 'E': state = NumberState.SAW_EXPONENT_LETTER; break; case ',': case '}': case ']': case ')': case -1: state = NumberState.DONE; break; default: if (Character.isDigit(c)) { state = NumberState.SAW_INTEGER_DIGITS; } else if (Character.isWhitespace(c)) { state = NumberState.DONE; } else { state = NumberState.INVALID; } break; } break; case SAW_INTEGER_DIGITS: switch(c) { case '.': state = NumberState.SAW_DECIMAL_POINT; break; case 'e': case 'E': state = NumberState.SAW_EXPONENT_LETTER; break; case ',': case '}': case ']': case ')': case -1: state = NumberState.DONE; break; default: if (Character.isDigit(c)) { state = NumberState.SAW_INTEGER_DIGITS; } else if (Character.isWhitespace(c)) { state = NumberState.DONE; } else { state = NumberState.INVALID; } break; } break; case SAW_DECIMAL_POINT: type = JsonTokenType.DOUBLE; if (Character.isDigit(c)) { state = NumberState.SAW_FRACTION_DIGITS; } else { state = NumberState.INVALID; } break; case SAW_FRACTION_DIGITS: switch(c) { case 'e': case 'E': state = NumberState.SAW_EXPONENT_LETTER; break; case ',': case '}': case ']': case ')': case -1: state = NumberState.DONE; break; default: if (Character.isDigit(c)) { state = NumberState.SAW_FRACTION_DIGITS; } else if (Character.isWhitespace(c)) { state = NumberState.DONE; } else { state = NumberState.INVALID; } break; } break; case SAW_EXPONENT_LETTER: type = JsonTokenType.DOUBLE; switch(c) { case '+': case '-': state = NumberState.SAW_EXPONENT_SIGN; break; default: if (Character.isDigit(c)) { state = NumberState.SAW_EXPONENT_DIGITS; } else { state = NumberState.INVALID; } break; } break; case SAW_EXPONENT_SIGN: if (Character.isDigit(c)) { state = NumberState.SAW_EXPONENT_DIGITS; } else { state = NumberState.INVALID; } break; case SAW_EXPONENT_DIGITS: switch(c) { case ',': case '}': case ']': case ')': state = NumberState.DONE; break; default: if (Character.isDigit(c)) { state = NumberState.SAW_EXPONENT_DIGITS; } else if (Character.isWhitespace(c)) { state = NumberState.DONE; } else { state = NumberState.INVALID; } break; } break; case SAW_MINUS_I: boolean sawMinusInfinity = true; char[] nfinity = new char[] { 'n', 'f', 'i', 'n', 'i', 't', 'y' }; for (int i = 0; i < nfinity.length; i++) { if (c != nfinity[i]) { sawMinusInfinity = false; break; } sb.append((char) c); c = buffer.read(); } if (sawMinusInfinity) { type = JsonTokenType.DOUBLE; switch(c) { case ',': case '}': case ']': case ')': case -1: state = NumberState.DONE; break; default: if (Character.isWhitespace(c)) { state = NumberState.DONE; } else { state = NumberState.INVALID; } break; } } else { state = NumberState.INVALID; } break; default: } switch(state) { case INVALID: throw new JsonParseException("Invalid JSON number"); case DONE: buffer.unread(c); String lexeme = sb.toString(); if (type == JsonTokenType.DOUBLE) { return new JsonToken(JsonTokenType.DOUBLE, Double.parseDouble(lexeme)); } else { long value = Long.parseLong(lexeme); if (value < Integer.MIN_VALUE || value > Integer.MAX_VALUE) { return new JsonToken(JsonTokenType.INT64, value); } else { return new JsonToken(JsonTokenType.INT32, (int) value); } } default: sb.append((char) c); } } } // CHECKSTYLE:ON /** * Reads {@code StringToken} from source. * * @return The string token. */ // CHECKSTYLE:OFF private JsonToken scanString(final char quoteCharacter) { StringBuilder sb = new StringBuilder(); while (true) { int c = buffer.read(); switch(c) { case '\\': c = buffer.read(); switch(c) { case '\'': sb.append('\''); break; case '"': sb.append('"'); break; case '\\': sb.append('\\'); break; case '/': sb.append('/'); break; case 'b': sb.append('\b'); break; case 'f': sb.append('\f'); break; case 'n': sb.append('\n'); break; case 'r': sb.append('\r'); break; case 't': sb.append('\t'); break; case 'u': int u1 = buffer.read(); int u2 = buffer.read(); int u3 = buffer.read(); int u4 = buffer.read(); if (u4 != -1) { String hex = new String(new char[] { (char) u1, (char) u2, (char) u3, (char) u4 }); sb.append((char) Integer.parseInt(hex, 16)); } break; default: throw new JsonParseException("Invalid escape sequence in JSON string '\\%c'.", c); } break; default: if (c == quoteCharacter) { return new JsonToken(JsonTokenType.STRING, sb.toString()); } if (c != -1) { sb.append((char) c); } } if (c == -1) { throw new JsonParseException("End of file in JSON string."); } } } private enum NumberState { SAW_LEADING_MINUS, SAW_LEADING_ZERO, SAW_INTEGER_DIGITS, SAW_DECIMAL_POINT, SAW_FRACTION_DIGITS, SAW_EXPONENT_LETTER, SAW_EXPONENT_SIGN, SAW_EXPONENT_DIGITS, SAW_MINUS_I, DONE, INVALID } private enum RegularExpressionState { IN_PATTERN, IN_ESCAPE_SEQUENCE, IN_OPTIONS, DONE, INVALID } }




© 2015 - 2024 Weber Informatics LLC | Privacy Policy