org.janusgraph.diskstorage.cql.strategy.GroupedExecutionStrategyBuilder Maven / Gradle / Ivy
// Copyright 2023 JanusGraph 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 org.janusgraph.diskstorage.cql.strategy;
import org.janusgraph.diskstorage.configuration.Configuration;
import org.janusgraph.diskstorage.cql.CQLStoreManager;
import org.janusgraph.diskstorage.util.backpressure.builder.QueryBackPressureBuilder;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.lang.reflect.Constructor;
import java.lang.reflect.InvocationTargetException;
public class GroupedExecutionStrategyBuilder {
private static final Logger log = LoggerFactory.getLogger(QueryBackPressureBuilder.class);
public static final String TOKEN_RANGE_AWARE = "tokenRangeAware";
public static final String REPLICAS_AWARE = "replicasAware";
private GroupedExecutionStrategyBuilder(){}
public static GroupedExecutionStrategy build(final Configuration configuration, final CQLStoreManager storeManager, final String className){
switch (className){
case TOKEN_RANGE_AWARE: return new TokenRangeAwareGroupedExecutionStrategy(configuration, storeManager);
case REPLICAS_AWARE: return new ReplicasAwareGroupedExecutionStrategy(configuration, storeManager);
default: return buildFromClassName(className, configuration, storeManager);
}
}
private static GroupedExecutionStrategy buildFromClassName(final String className, final Configuration configuration, final CQLStoreManager storeManager){
Class implementationClass;
try {
implementationClass = Class.forName(className);
} catch (ClassNotFoundException e) {
throw new IllegalArgumentException("No class found with class name: "+className);
}
if(!GroupedExecutionStrategy.class.isAssignableFrom(implementationClass)){
throw new IllegalArgumentException(className + "isn't a subclass of "+GroupedExecutionStrategy.class.getName());
}
final GroupedExecutionStrategy result;
Constructor constructorWithConfigurationAndSessionParams = null;
for (Constructor constructor : implementationClass.getDeclaredConstructors()) {
if (constructor.getParameterCount() == 2 && Configuration.class.isAssignableFrom(constructor.getParameterTypes()[0]) &&
CQLStoreManager.class.isAssignableFrom(constructor.getParameterTypes()[1])){
constructorWithConfigurationAndSessionParams = constructor;
break;
}
}
try {
if(constructorWithConfigurationAndSessionParams == null){
throw new IllegalArgumentException(className + " has no a public constructor which accepts "
+Configuration.class.getName() + " and "+CQLStoreManager.class.getName()+" parameters.");
}
result = (GroupedExecutionStrategy) constructorWithConfigurationAndSessionParams.newInstance(configuration, storeManager);
} catch (InstantiationException | IllegalAccessException | InvocationTargetException e) {
throw new IllegalStateException("Couldn't create a new instance of "+className +
". Please, check that the constructor which accepts "+Configuration.class.getName()+" and "+CQLStoreManager.class.getName()
+" is public. If the necessary public constructor exists, please, check that invocation of this constructor doesn't throw an exception.", e);
}
log.info("Initiated custom GroupedExecutionStrategy {}", className);
return result;
}
}