com.github.jsonldjava.core.Context Maven / Gradle / Ivy

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package com.github.jsonldjava.core;

import static com.github.jsonldjava.core.JsonLdUtils.compareShortestLeast;
import static com.github.jsonldjava.utils.Obj.newMap;

import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;
import java.util.regex.Pattern;

import com.github.jsonldjava.core.JsonLdError.Error;
import com.github.jsonldjava.utils.JsonLdUrl;
import com.github.jsonldjava.utils.Obj;

/**
 * A helper class which still stores all the values in a map but gives member
 * variables easily access certain keys
 *
 * @author tristan
 *
 */
public class Context extends LinkedHashMap {

    private static final long serialVersionUID = 2894534897574805571L;

    private static final Pattern URL_PATTERN = Pattern.compile("^https?://.*$", Pattern.CASE_INSENSITIVE);
    private JsonLdOptions options;
    private Map termDefinitions;
    public Map inverse = null;

    public Context() {
        this(new JsonLdOptions());
    }

    public Context(JsonLdOptions opts) {
        super();
        init(opts);
    }

    public Context(Map map, JsonLdOptions opts) {
        super(map);
        checkEmptyKey(map);
        init(opts);
    }

    public Context(Map map) {
        super(map);
        checkEmptyKey(map);
        init(new JsonLdOptions());
    }

    public Context(Object context, JsonLdOptions opts) {
        // TODO: load remote context
        super(context instanceof Map ? (Map) context : null);
        init(opts);
    }

    private void init(JsonLdOptions options) {
        this.options = options;
        if (options.getBase() != null) {
            this.put(JsonLdConsts.BASE, options.getBase());
        }
        this.termDefinitions = newMap();
    }

    /**
     * Value Compaction Algorithm
     *
     * http://json-ld.org/spec/latest/json-ld-api/#value-compaction
     *
     * @param activeProperty
     *            The Active Property
     * @param value
     *            The value to compact
     * @return The compacted value
     */
    public Object compactValue(String activeProperty, Map value) {
        // 1)
        int numberMembers = value.size();
        // 2)
        if (value.containsKey(JsonLdConsts.INDEX)
                && JsonLdConsts.INDEX.equals(this.getContainer(activeProperty))) {
            numberMembers--;
        }
        // 3)
        if (numberMembers > 2) {
            return value;
        }
        // 4)
        final String typeMapping = getTypeMapping(activeProperty);
        final String languageMapping = getLanguageMapping(activeProperty);
        if (value.containsKey(JsonLdConsts.ID)) {
            // 4.1)
            if (numberMembers == 1 && JsonLdConsts.ID.equals(typeMapping)) {
                return compactIri((String) value.get(JsonLdConsts.ID));
            }
            // 4.2)
            if (numberMembers == 1 && JsonLdConsts.VOCAB.equals(typeMapping)) {
                return compactIri((String) value.get(JsonLdConsts.ID), true);
            }
            // 4.3)
            return value;
        }
        final Object valueValue = value.get(JsonLdConsts.VALUE);
        // 5)
        if (value.containsKey(JsonLdConsts.TYPE)
                && Obj.equals(value.get(JsonLdConsts.TYPE), typeMapping)) {
            return valueValue;
        }
        // 6)
        if (value.containsKey(JsonLdConsts.LANGUAGE)) {
            // TODO: SPEC: doesn't specify to check default language as well
            if (Obj.equals(value.get(JsonLdConsts.LANGUAGE), languageMapping) || Obj
                    .equals(value.get(JsonLdConsts.LANGUAGE), this.get(JsonLdConsts.LANGUAGE))) {
                return valueValue;
            }
        }
        // 7)
        if (numberMembers == 1 && (!(valueValue instanceof String)
                || !this.containsKey(JsonLdConsts.LANGUAGE)
                || (termDefinitions.containsKey(activeProperty)
                        && getTermDefinition(activeProperty).containsKey(JsonLdConsts.LANGUAGE)
                        && languageMapping == null))) {
            return valueValue;
        }
        // 8)
        return value;
    }

    /**
     * Context Processing Algorithm
     *
     * http://json-ld.org/spec/latest/json-ld-api/#context-processing-algorithms
     *
     * @param localContext
     *            The Local Context object.
     * @param remoteContexts
     *            The list of Strings denoting the remote Context URLs.
     * @return The parsed and merged Context.
     * @throws JsonLdError
     *             If there is an error parsing the contexts.
     */
    public Context parse(Object localContext, List remoteContexts) throws JsonLdError {
        if (remoteContexts == null) {
            remoteContexts = new ArrayList();
        }
        return parse(localContext, remoteContexts, false);
    }

    /**
     * Helper method used to work around logic errors related to the recursive
     * nature of the JSONLD-API Context Processing Algorithm.
     *
     * @param localContext
     *            The Local Context object.
     * @param remoteContexts
     *            The list of Strings denoting the remote Context URLs.
     * @param parsingARemoteContext
     *            True if localContext represents a remote context that has been
     *            parsed and sent into this method and false otherwise. This
     *            must be set to know whether to propagate the @code{@base} key
     *            from the context to the result.
     * @return The parsed and merged Context.
     * @throws JsonLdError
     *             If there is an error parsing the contexts.
     */
    private Context parse(Object localContext, final List remoteContexts,
            boolean parsingARemoteContext) throws JsonLdError {
        // 1. Initialize result to the result of cloning active context.
        Context result = this.clone(); // TODO: clone?
        // 2)
        if (!(localContext instanceof List)) {
            final Object temp = localContext;
            localContext = new ArrayList