com.github.fge.jsonschema.jsonpointer.JsonNodeResolver Maven / Gradle / Ivy

Go to download

Show more of this group Show more artifacts with this name
Show all versions of json-schema-core Show documentation

Core processing architecture for json-schema-validator

There is a newer version: 1.2.5

/*
 * Copyright (c) 2013, Francis Galiegue 
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the Lesser GNU General Public License as
 * published by the Free Software Foundation, either version 3 of the
 * License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * Lesser GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see .
 */

package com.github.fge.jsonschema.jsonpointer;

import com.fasterxml.jackson.databind.JsonNode;
import net.jcip.annotations.Immutable;

/**
 * Implementation of {@link TokenResolver} for {@link JsonNode}
 *
 * The JSON Pointer specification specifies that for arrays, indices must
 * not have leading zeroes (save for {@code 0} itself). This class handles
 * this.
 */
@Immutable
public final class JsonNodeResolver
    extends TokenResolver
{
    /**
     * Zero
     */
    private static final char ZERO = '0';

    public JsonNodeResolver(final ReferenceToken token)
    {
        super(token);
    }

    @Override
    public JsonNode get(final JsonNode node)
    {
        if (node == null || !node.isContainerNode())
            return null;
        final String raw = token.getRaw();
        return node.isObject() ? node.get(raw) : node.get(arrayIndexFor(raw));
    }

    /**
     * Return an array index corresponding to the given (raw) reference token
     *
     * If no array index can be found, -1 is returned. As the result is used
     * with {@link JsonNode#get(int)}, we are guaranteed correct results, since
     * this will return {@code null} in this case.
     *
     * @param raw the raw token, as a string
     * @return the index, or -1 if the index is invalid
     */
    private static int arrayIndexFor(final String raw)
    {
        /*
         * Empty? No dice.
         */
        if (raw.isEmpty())
            return -1;
        /*
         * Leading zeroes are not allowed in number-only refTokens for arrays.
         * But then, 0 followed by anything else than a number is invalid as
         * well. So, if the string starts with '0', return 0 if the token length
         * is 1 or -1 otherwise.
         */
        if (raw.charAt(0) == ZERO)
            return raw.length() == 1 ? 0 : -1;

        /*
         * Otherwise, parse as an int. If we can't, -1.
         */
        try {
            return Integer.parseInt(raw);
        } catch (NumberFormatException ignored) {
            return -1;
        }
    }
}