/**
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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.apache.drill.exec.resolver;
import java.util.List;
import org.apache.drill.common.expression.FunctionCall;
import org.apache.drill.exec.expr.fn.DrillFuncHolder;
public class DefaultFunctionResolver implements FunctionResolver {
@Override
public DrillFuncHolder getBestMatch(List<DrillFuncHolder> methods,FunctionCall call) {
int bestcost = Integer.MAX_VALUE;
int currcost = Integer.MAX_VALUE;
DrillFuncHolder bestmatch = null;
for (DrillFuncHolder h : methods) {
currcost = TypeCastRules.getCost(call, h);
// if cost is lower than 0, func implementation is not matched, either w/ or w/o implicit casts
if (currcost < 0 ) {
continue;
}
if (currcost < bestcost) {
bestcost = currcost;
bestmatch = h;
}
}
if (bestcost < 0) {
//did not find a matched func implementation, either w/ or w/o implicit casts
//TODO: raise exception here?
return null;
} else {
return bestmatch;
}
}
}