| /* |
| * 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.physical.impl.common; |
| |
| import com.sun.codemodel.JVar; |
| import io.netty.buffer.DrillBuf; |
| import org.apache.calcite.util.Pair; |
| import org.apache.drill.exec.expr.ClassGenerator; |
| import org.apache.drill.exec.expr.holders.ValueHolder; |
| import org.apache.drill.exec.ops.FragmentContext; |
| import org.apache.drill.shaded.guava.com.google.common.base.Function; |
| |
| import java.lang.reflect.Field; |
| import java.util.HashMap; |
| import java.util.Map; |
| |
| public class CodeGenMemberInjector { |
| |
| /** |
| * Generated code for a class may have several class members, they |
| * are initialized by invoking this method when the instance created. |
| * |
| * @param cg the class generator |
| * @param instance the class instance created by the compiler |
| * @param context the fragment context |
| */ |
| public static void injectMembers(ClassGenerator<?> cg, Object instance, FragmentContext context) { |
| Map<Integer, Object> cachedInstances = new HashMap<>(); |
| for (Map.Entry<Pair<Integer, JVar>, Function<DrillBuf, ? extends ValueHolder>> setter : cg.getConstantVars().entrySet()) { |
| try { |
| JVar var = setter.getKey().getValue(); |
| Integer depth = setter.getKey().getKey(); |
| Object varInstance = getFieldInstance(instance, depth, cachedInstances); |
| Field field = varInstance.getClass().getDeclaredField(var.name()); |
| field.setAccessible(true); |
| field.set(varInstance, setter.getValue().apply(context.getManagedBuffer())); |
| } catch (ReflectiveOperationException e) { |
| throw new RuntimeException(e); |
| } |
| } |
| } |
| |
| private static Object getFieldInstance(Object instance, Integer depth, Map<Integer, Object> cache) throws ReflectiveOperationException { |
| if (depth <= 1) { |
| return instance; |
| } |
| Object methodInstance = cache.get(depth); |
| if (methodInstance != null) { |
| return methodInstance; |
| } |
| methodInstance = getFieldInstance(instance, depth); |
| cache.put(depth, methodInstance); |
| return methodInstance; |
| } |
| |
| private static Object getFieldInstance(Object instance, Integer depth) throws ReflectiveOperationException { |
| if (depth <= 1) { |
| return instance; |
| } |
| Field field = instance.getClass().getDeclaredField(ClassGenerator.INNER_CLASS_FIELD_NAME); |
| field.setAccessible(true); |
| return getFieldInstance(field.get(instance), depth - 1); |
| } |
| } |