org.normandra.meta.EntityMetaCollection.java Source code

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Here is the source code for org.normandra.meta.EntityMetaCollection.java

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package org.normandra.meta;

import org.apache.commons.lang.NullArgumentException;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.Collections;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;

/**
 * a set of entity meta instances
 *
 * @author bowen
 */
public class EntityMetaCollection implements EntityMetaLookup, Iterable<EntityMeta> {
    private final Map<Class, EntityMeta> classMap = new HashMap<>();

    public EntityMetaCollection(final Iterable<EntityMeta> metas) {
        if (null == metas) {
            throw new NullArgumentException("metadata");
        }
        for (final EntityMeta entity : metas) {
            this.classMap.put(entity.getType(), entity);
        }
    }

    @Override
    public EntityMeta getMeta(final Class<?> clazz) {
        if (null == clazz) {
            return null;
        }
        final EntityMeta existing = this.classMap.get(clazz);
        if (existing != null) {
            return existing;
        }
        final List<EntityMeta> list = this.findMeta(clazz);
        if (list.isEmpty()) {
            return null;
        }
        if (list.size() != 1) {
            throw new IllegalArgumentException("Found multiple entities for [" + clazz + "].");
        }
        return list.get(0);
    }

    @Override
    public final EntityMeta getMeta(final String labelOrType) {
        if (null == labelOrType || labelOrType.isEmpty()) {
            return null;
        }
        for (final EntityMeta meta : this.classMap.values()) {
            if (labelOrType.equalsIgnoreCase(meta.getName())) {
                return meta;
            }
            for (final TableMeta table : meta) {
                if (!table.isJoinTable() && labelOrType.equalsIgnoreCase(table.getName())) {
                    return meta;
                }
            }
        }
        return null;
    }

    @Override
    public final List<EntityMeta> findMeta(final Class<?> clazz) {
        if (null == clazz) {
            return Collections.emptyList();
        }
        final EntityMeta existing = this.classMap.get(clazz);
        if (existing != null) {
            return Arrays.asList(existing);
        }
        final List<EntityMeta> list = new ArrayList<>(4);
        for (final Map.Entry<Class, EntityMeta> entry : this.classMap.entrySet()) {
            final Class<?> entityClass = entry.getKey();
            final EntityMeta entityMeta = entry.getValue();
            if (clazz.isAssignableFrom(entityClass)) {
                list.add(entityMeta);
            }
        }
        if (list.isEmpty()) {
            return Collections.emptyList();
        } else {
            return Collections.unmodifiableList(list);
        }
    }

    @Override
    public final EntityContext findContext(final Class<?> clazz) {
        final List<EntityMeta> list = this.findMeta(clazz);
        if (list.isEmpty()) {
            return null;
        }
        if (list.size() == 1) {
            // simple entity
            final EntityMeta meta = list.get(0);
            return new SingleEntityContext(meta);
        } else {
            // inherited entity
            return new HierarchyEntityContext(list);
        }
    }

    @Override
    public Collection<EntityMeta> list() {
        return Collections.unmodifiableCollection(this.classMap.values());
    }

    @Override
    public boolean contains(final Class<?> clazz) {
        return !this.findMeta(clazz).isEmpty();
    }

    @Override
    public boolean contains(final EntityMeta meta) {
        if (null == meta) {
            return false;
        }
        for (final Map.Entry<Class, EntityMeta> entry : this.classMap.entrySet()) {
            if (meta == entry.getValue() || meta.compareTo(entry.getValue()) == 0) {
                return true;
            }
        }
        return false;
    }

    @Override
    public int size() {
        return this.classMap.size();
    }

    @Override
    public Iterator<EntityMeta> iterator() {
        return Collections.unmodifiableCollection(this.classMap.values()).iterator();
    }
}