/*
 * Copyright 2016-2018 shardingsphere.io.
 * <p>
 * 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.
 * </p>
 */

package io.shardingsphere.core.jdbc.core;

import com.google.common.eventbus.Subscribe;
import io.shardingsphere.core.constant.ConnectionMode;
import io.shardingsphere.core.constant.DatabaseType;
import io.shardingsphere.core.exception.ShardingException;
import io.shardingsphere.core.executor.ExecutorEngine;
import io.shardingsphere.core.jdbc.metadata.JDBCTableMetaDataConnectionManager;
import io.shardingsphere.core.metadata.ShardingMetaData;
import io.shardingsphere.core.rule.ShardingRule;
import io.shardingsphere.jdbc.orchestration.internal.eventbus.jdbc.JDBCEventBusEvent;
import io.shardingsphere.jdbc.orchestration.internal.jdbc.datasource.CircuitBreakerDataSource;
import lombok.Getter;
import lombok.RequiredArgsConstructor;

import javax.sql.DataSource;
import java.sql.Connection;
import java.sql.SQLException;
import java.util.Collection;
import java.util.LinkedHashMap;
import java.util.LinkedList;
import java.util.Map;

/**
 * Sharding runtime context.
 * 
 * @author gaohongtao
 * @author panjuan
 */
@RequiredArgsConstructor
@Getter
public final class ShardingContext {
    
    private final Map<String, DataSource> dataSourceMap;
    
    private final ShardingRule shardingRule;
    
    private final DatabaseType databaseType;
    
    private final ExecutorEngine executorEngine;
    
    private ShardingMetaData metaData;
    
    private final ConnectionMode connectionMode;
    
    private final boolean showSQL;
    
    private Collection<String> disabledDataSourceNames = new LinkedList<>();
    
    private Collection<String> circuitBreakerDataSourceNames = new LinkedList<>();
    
    /**
     * Renew disable dataSource names.
     *
     * @param jdbcEventBusEvent jdbc event bus event
     */
    @Subscribe
    public void renewDisabledDataSourceNames(final JDBCEventBusEvent jdbcEventBusEvent) {
        disabledDataSourceNames = jdbcEventBusEvent.getDisabledDataSourceNames();
        metaData = new ShardingMetaData(
                getDataSourceURLs(getDataSourceMap()), shardingRule, getDatabaseType(), executorEngine.getExecutorService(), new JDBCTableMetaDataConnectionManager(getDataSourceMap()));
    }
    
    /**
     * Renew circuit breaker dataSource names.
     *
     * @param jdbcEventBusEvent jdbc event bus event
     */
    @Subscribe
    public void renewCircuitBreakerDataSourceNames(final JDBCEventBusEvent jdbcEventBusEvent) {
        circuitBreakerDataSourceNames = jdbcEventBusEvent.getCircuitBreakerDataSource();
        metaData = new ShardingMetaData(
                getDataSourceURLs(getDataSourceMap()), shardingRule, getDatabaseType(), executorEngine.getExecutorService(), new JDBCTableMetaDataConnectionManager(getDataSourceMap()));
    }
    
    private static Map<String, String> getDataSourceURLs(final Map<String, DataSource> dataSourceMap) {
        Map<String, String> result = new LinkedHashMap<>(dataSourceMap.size(), 1);
        for (Map.Entry<String, DataSource> entry : dataSourceMap.entrySet()) {
            result.put(entry.getKey(), getDataSourceURL(entry.getValue()));
        }
        return result;
    }
    
    private static String getDataSourceURL(final DataSource dataSource) {
        try (Connection connection = dataSource.getConnection()) {
            return connection.getMetaData().getURL();
        } catch (final SQLException ex) {
            throw new ShardingException(ex);
        }
    }
    
    /**
     * Get available data source map.
     *
     * @return available data source map
     */
    public Map<String, DataSource> getDataSourceMap() {
        if (!getCircuitBreakerDataSourceNames().isEmpty()) {
            return getCircuitBreakerDataSourceMap();
        }
        
        if (!getDisabledDataSourceNames().isEmpty()) {
            return getAvailableDataSourceMap();
        }
        return dataSourceMap;
    }
    
    private Map<String, DataSource> getAvailableDataSourceMap() {
        Map<String, DataSource> result = new LinkedHashMap<>(dataSourceMap);
        for (String each : disabledDataSourceNames) {
            result.remove(each);
        }
        return result;
    }
    
    private Map<String, DataSource> getCircuitBreakerDataSourceMap() {
        Map<String, DataSource> result = new LinkedHashMap<>();
        for (String each : dataSourceMap.keySet()) {
            result.put(each, new CircuitBreakerDataSource());
        }
        return result;
    }
}

@@ -1176,16 +1176,25 @@
 us.jdbc.
+sharding.
 JDBCEven
@@ -1317,24 +1317,47 @@
 bok.Getter;%0A
+import lombok.NonNull;%0A
 import lombo
@@ -1949,32 +1949,45 @@
 torEngine;%0A    %0A
+    @NonNull%0A
     private Shar

use @NonNull