org.horizontaldb.shard.ShardContextEnricher.java Source code

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Here is the source code for org.horizontaldb.shard.ShardContextEnricher.java

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/*
 * Copyright 2014 David Lukacs
 *
 * 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 org.horizontaldb.shard;

import java.util.Collection;
import java.util.HashSet;
import java.util.LinkedList;
import java.util.Map;
import java.util.Map.Entry;
import java.util.Set;

import javax.inject.Inject;

import org.horizontaldb.shard.annotation.ShardBean;
import org.horizontaldb.shard.annotation.ShardBeans;
import org.horizontaldb.shard.resolver.ShardBeanResolver;
import org.horizontaldb.util.BeanUtils;
import org.springframework.beans.factory.NoSuchBeanDefinitionException;

public abstract class ShardContextEnricher {
    @Inject
    private ConversationRegistry registry;

    @Inject
    private BeanUtils beanUtils;

    private Map<Class<?>, ShardBeanResolver> targetResolvers;
    private Map<Class<?>, ShardBeanEnricher> targetEnrichers;

    public void setTargetResolvers(Map<Class<?>, ShardBeanResolver> targetResolvers) {
        this.targetResolvers = targetResolvers;
    }

    public void setTargetEnrichers(Map<Class<?>, ShardBeanEnricher> targetEnrichers) {
        this.targetEnrichers = targetEnrichers;
    }

    protected Collection<Object> doSetup(ShardBeans shardBeans, ShardContext shardContext) {
        Collection<Object> resolvedBeans = new LinkedList<>();

        Set<ShardBean> resolvedTypes = new HashSet<>();

        for (ShardBean shardBean : shardBeans.value()) {
            if (!resolvedTypes.contains(shardBean)) {
                resolvedTypes.add(shardBean);

                resolvedBeans.add(populateShardContextWithBean(shardBean, shardContext));
            }
        }

        for (Object bean : resolvedBeans) {
            enricherDoSetup(bean, shardContext);
        }

        return resolvedBeans;
    }

    protected Object doSetup(ShardBean shardBean, ShardContext shardContext) {
        Object resolvedBean = populateShardContextWithBean(shardBean, shardContext);

        enricherDoSetup(resolvedBean, shardContext);

        return resolvedBean;
    }

    protected void doTearDown(Collection<Object> beans, ShardContext shardContext) {
        for (Object bean : beans) {
            doTearDown(bean, shardContext);
        }
    }

    protected void doTearDown(Object bean, ShardContext shardContext) {
        enricherDoTearDown(bean, shardContext);
    }

    private Object populateShardContextWithBean(ShardBean shardBean, ShardContext shardContext) {
        Object bean = getResolver(shardBean.value()).getBean(shardBean.value(), shardContext);

        if (bean == null) {
            throw new NoSuchBeanDefinitionException(shardBean.value().toString());
        }

        registerResourceWithConversation(shardContext, bean);

        shardContext.setBean(shardBean.value(), bean);

        return bean;
    }

    private void registerResourceWithConversation(ShardContext shardContext, Object bean) {
        registry.addResource(shardContext.getClientId(), bean);
    }

    /*
     * returns the first matching resolver, based on equality, then assignability
     */
    private ShardBeanResolver getResolver(Class<?> value) {
        ShardBeanResolver retval = null;

        if (targetResolvers != null) {
            for (Entry<Class<?>, ShardBeanResolver> entry : targetResolvers.entrySet()) {
                if (entry.getKey().equals(value) || entry.getKey().isAssignableFrom(value)) {
                    retval = entry.getValue();

                    break;
                }
            }
        }

        if (retval == null) {
            throw new IllegalStateException("ShardContextEnricher is not configured for [" + value + "]");
        }

        return retval;
    }

    private void enricherDoSetup(Object bean, ShardContext shardContext) {
        Object target = beanUtils.unpackDynamicProxy(bean);

        ShardBeanEnricher enricher = getEnricher(target);

        if (enricher != null) {
            enricher.setup(target, shardContext);
        }
    }

    private void enricherDoTearDown(Object bean, ShardContext shardContext) {
        Object target = beanUtils.unpackDynamicProxy(bean);

        ShardBeanEnricher enricher = getEnricher(target);

        if (enricher != null) {
            enricher.tearDown(target, shardContext);
        }
    }

    /*
     * returns the first matching enricher for a bean, based on the key's assignment compatibility. the return value
     * could be null if there is no match
     */
    private ShardBeanEnricher getEnricher(Object bean) {
        ShardBeanEnricher retval = null;

        if (targetEnrichers != null) {
            for (Entry<Class<?>, ShardBeanEnricher> entry : targetEnrichers.entrySet()) {
                if (entry.getKey().isInstance(bean)) {
                    retval = entry.getValue();

                    break;
                }
            }
        }

        return retval;
    }

}