cz.encircled.joiner.query.join.DefaultJoinGraphRegistry Maven / Gradle / Ivy

Go to download
package cz.encircled.joiner.query.join;

import cz.encircled.joiner.exception.JoinerException;
import cz.encircled.joiner.util.Assert;

import java.util.ArrayList;
import java.util.Collection;
import java.util.List;
import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;
import java.util.stream.Collectors;

/**
 * ConcurrentHashMap-based implementation of {@link JoinGraphRegistry}
 *
 * @author Vlad on 15-Aug-16.
 */
public class DefaultJoinGraphRegistry implements JoinGraphRegistry {

    private final Map>> registry = new ConcurrentHashMap<>();

    @Override
    public void registerJoinGraph(Object graphName, Collection joins, Class... rootClasses) {
        Assert.notNull(graphName);
        Assert.notNull(joins);
        Assert.notNull(rootClasses);
        Assert.assertThat(rootClasses.length > 0);

        for (Class clazz : rootClasses) {
            registry.computeIfAbsent(clazz, c -> new ConcurrentHashMap<>());
            Map> joinsOfClass = registry.get(clazz);
            if (joinsOfClass.containsKey(graphName)) {
                throw new JoinerException(String.format("JoinGraph with name [%s] is already defined for the class [%s]", graphName, clazz.getName()));
            } else {
                joinsOfClass.put(graphName, new ArrayList<>(joins));
            }
        }
    }

    @Override
    public void replaceJoinGraph(Object graphName, Collection joins, Class... rootClasses) {
        Assert.notNull(graphName);
        Assert.notNull(joins);
        Assert.notNull(rootClasses);
        Assert.assertThat(rootClasses.length > 0);

        for (Class clazz : rootClasses) {
            Map> existing = registry.get(clazz);
            if (existing != null) {
                if (existing.containsKey(graphName)) {
                    existing.put(graphName, new ArrayList<>(joins));
                    continue;
                }
            }

            throw new JoinerException(String.format("JoinGraph with name [%s] is not defined for the class [%s]", graphName, clazz.getName()));
        }
    }

    @Override
    public List getJoinGraph(Class clazz, Object name) {
        // TODO add tests for join description modifying
        Map> joinsOfClass = registry.get(clazz);
        if (joinsOfClass != null) {
            List joins = joinsOfClass.get(name);
            if (joins != null) {
                return joins.stream().map(JoinDescription::copy).collect(Collectors.toList());
            }
        }

        throw new JoinerException(String.format("JoinGraph with name [%s] is not defined for class [%s]", name, clazz));
    }

}