InverseContext.java

/*
 * Copyright 2020 the original author or authors.
 *
 * 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 no.hasmac.jsonld.context;

import it.unimi.dsi.fastutil.objects.Object2ObjectArrayMap;
import it.unimi.dsi.fastutil.objects.Object2ObjectLinkedOpenHashMap;
import it.unimi.dsi.fastutil.objects.Object2ObjectMap;
import it.unimi.dsi.fastutil.objects.Object2ObjectOpenHashMap;

import java.util.Map;
import java.util.Optional;

public final class InverseContext {

    private final Map<String, Map<String, Map<String, Map<String, String>>>> context;

    public InverseContext() {
        this.context = new Object2ObjectOpenHashMap<>();
    }

    private void set(final String variable, final String container, final String type, final String key, final String value) {
        context.computeIfAbsent(variable, x -> new Object2ObjectOpenHashMap<>())
                .computeIfAbsent(container, x -> new Object2ObjectOpenHashMap<>())
                .computeIfAbsent(type, x -> new Object2ObjectLinkedOpenHashMap<>())
                .put(key, value);
    }

    private boolean doesNotContain(final String variable, final String container, final String type, final String key) {
        var stringMapMap = context.get(variable);
        if(stringMapMap != null){
            var stringMapMap1 = stringMapMap.get(container);
            if(stringMapMap1 != null){
                var stringStringMap = stringMapMap1.get(type);
                if(stringStringMap != null){
                    return !stringStringMap.containsKey(key);
                }
            }
        }
        return true;

    }

    public boolean contains(final String variable) {
        return context.containsKey(variable);
    }

    public boolean contains(final String variable, final String container, final String type) {
        var stringMapMap = context.get(variable);
        if(stringMapMap != null){
            var stringMapMap1 = stringMapMap.get(container);
            if(stringMapMap1 != null){
                return stringMapMap1.containsKey(type);
            }
        }
        return false;
    }

    public boolean contains(final String variable, final String container, final String type, final String key) {
        return contains(variable)
                    && context.get(variable).containsKey(container)
                    && context.get(variable).get(container).containsKey(type)
                    && context.get(variable).get(container).get(type).containsKey(key);
    }

    public InverseContext setIfAbsent(final String variable, final String container, final String type, final String key, final String value) {
        if (doesNotContain(variable, container, type, key)) {
            set(variable, container, type, key, value);
        }
        return this;
    }

    public Optional<String> get(final String variable, final String container, final String type, final String key) {
        if (doesNotContain(variable, container, type, key)) {
            return Optional.empty();
        }
        return Optional.ofNullable(context.get(variable).get(container).get(type).get(key));
    }

    public String getNullable(final String variable, final String container, final String type, final String key) {
        var map1 = context.get(variable);
        if(map1 == null){
            return null;
        }
        var map2 = map1.get(container);
        if(map2 == null){
            return null;
        }
        var map3 = map2.get(type);
        if(map3 == null){
            return null;
        }
        return map3.get(key);
    }

    public Map<String, String> getNullable(final String variable, final String container, final String type) {
        var map1 = context.get(variable);
        if(map1 == null){
            return null;
        }
        var map2 = map1.get(container);
        if(map2 == null){
            return null;
        }
       return map2.get(type);
    }
}