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/* * Copyright 2002-2019 the original author or 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 * * https://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.springframework.data.gemfire.function; import java.lang.reflect.Method; import java.util.Map; import java.util.Set; import org.apache.geode.cache.Region; import org.apache.geode.cache.execute.Function; import org.apache.geode.cache.execute.FunctionContext; import org.apache.geode.cache.execute.RegionFunctionContext; import org.apache.geode.cache.execute.ResultSender; import org.apache.geode.cache.partition.PartitionRegionHelper; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import org.springframework.data.gemfire.function.annotation.Filter; import org.springframework.data.gemfire.function.annotation.RegionData; import org.springframework.data.gemfire.util.ArrayUtils; import org.springframework.util.Assert; /** * {@link FunctionArgumentResolver} implementation capable of resolving the {@link FunctionContext} passed to * a {@link Function} implementation during invocation. * * @author David Turanski * @author John Blum * @see java.lang.reflect.Method * @see org.apache.geode.cache.Region * @see org.apache.geode.cache.execute.Function * @see org.apache.geode.cache.execute.FunctionContext * @see org.apache.geode.cache.execute.RegionFunctionContext * @see org.apache.geode.cache.execute.ResultSender * @see org.apache.geode.cache.partition.PartitionRegionHelper * @see org.springframework.data.gemfire.function.annotation.Filter * @see org.springframework.data.gemfire.function.annotation.RegionData * @see org.springframework.data.gemfire.function.PdxFunctionArgumentResolver * @since 1.3.0 */ class FunctionContextInjectingArgumentResolver extends PdxFunctionArgumentResolver { private final Logger logger = LoggerFactory.getLogger(FunctionContextInjectingArgumentResolver.class); private final int filterParameterPosition; private final int functionContextParameterPosition; private final int regionParameterPosition; private final int resultSenderParameterPosition; private final Method method; FunctionContextInjectingArgumentResolver(Method method) { this.method = method; int regionDataAnnotationParameterPosition = GemfireFunctionUtils.getAnnotationParameterPosition(method, RegionData.class, new Class[] { Map.class }); int regionTypeParameterPosition = getArgumentTypePosition(method, Region.class); if (regionDataAnnotationParameterPosition >= 0 && regionTypeParameterPosition >= 0) { Assert.isTrue(regionDataAnnotationParameterPosition == regionTypeParameterPosition, String.format( "Function method signature for method %s cannot contain an @RegionData parameter and a different Region type parameter", method.getName())); } regionParameterPosition = (regionDataAnnotationParameterPosition >= 0 ? regionDataAnnotationParameterPosition : (regionTypeParameterPosition >= 0 ? regionTypeParameterPosition : -1)); filterParameterPosition = GemfireFunctionUtils.getAnnotationParameterPosition(method, Filter.class, new Class[] { Set.class }); if (regionParameterPosition >= 0 && filterParameterPosition >= 0) { Assert.state(regionParameterPosition != filterParameterPosition, "region parameter and filter parameter must be different"); } functionContextParameterPosition = getArgumentTypePosition(method, FunctionContext.class); resultSenderParameterPosition = getArgumentTypePosition(method, ResultSender.class); } @Override public Method getFunctionAnnotatedMethod() { return this.method; } @Override public Object[] resolveFunctionArguments(FunctionContext functionContext) { Object[] args = super.resolveFunctionArguments(functionContext); if (functionContext instanceof RegionFunctionContext) { if (this.regionParameterPosition >= 0) { args = ArrayUtils.insert(args, regionParameterPosition, getRegionForContext((RegionFunctionContext) functionContext)); } if (this.filterParameterPosition >= 0) { args = ArrayUtils.insert(args, filterParameterPosition, ((RegionFunctionContext) functionContext).getFilter()); } } if (this.functionContextParameterPosition >= 0) { args = ArrayUtils.insert(args, functionContextParameterPosition, functionContext); } if (this.resultSenderParameterPosition >= 0) { args = ArrayUtils.insert(args, resultSenderParameterPosition, functionContext.getResultSender()); } Assert.isTrue(args.length == this.method.getParameterTypes().length, String.format("Wrong number of arguments for method [%s]; Expected [%d], but was [%d]", this.method.getName(), this.method.getParameterTypes().length, args.length)); return args; } private Region<?, ?> getRegionForContext(RegionFunctionContext regionFunctionContext) { Region<?, ?> region = regionFunctionContext.getDataSet(); if (PartitionRegionHelper.isPartitionedRegion(region)) { if (logger.isDebugEnabled()) { logger.debug("this is a partitioned region - filtering local data for context"); } region = PartitionRegionHelper.getLocalDataForContext(regionFunctionContext); } if (logger.isDebugEnabled()) { logger.debug("Region contains {} items", region.size()); } return region; } int getArgumentTypePosition(Method method, Class<?> requiredType) { int index = 0; int position = -1; for (Class<?> parameterType : method.getParameterTypes()) { if (requiredType.isAssignableFrom(parameterType)) { Assert.state(position < 0, String.format( "Method [%1$s] signature cannot contain more than one parameter of type [%2$s].", method.getName(), requiredType.getName())); position = index; } index++; } return position; } }