001/*
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements.  See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License.  You may obtain a copy of the License at
008 *
009 *      http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017package org.apache.camel.reifier;
018
019import java.util.concurrent.ScheduledExecutorService;
020
021import org.apache.camel.Expression;
022import org.apache.camel.Processor;
023import org.apache.camel.model.ProcessorDefinition;
024import org.apache.camel.model.ProcessorDefinitionHelper;
025import org.apache.camel.model.ThrottleDefinition;
026import org.apache.camel.model.language.ExpressionDefinition;
027import org.apache.camel.processor.Throttler;
028import org.apache.camel.spi.RouteContext;
029
030public class ThrottleReifier extends ExpressionReifier<ThrottleDefinition> {
031
032    public ThrottleReifier(ProcessorDefinition<?> definition) {
033        super((ThrottleDefinition)definition);
034    }
035
036    @Override
037    public Processor createProcessor(RouteContext routeContext) throws Exception {
038        boolean async = definition.getAsyncDelayed() != null && definition.getAsyncDelayed();
039        boolean shutdownThreadPool = ProcessorDefinitionHelper.willCreateNewThreadPool(routeContext, definition, true);
040        ScheduledExecutorService threadPool = ProcessorDefinitionHelper.getConfiguredScheduledExecutorService(routeContext, "Throttle", definition, true);
041
042        // should be default 1000 millis
043        long period = definition.getTimePeriodMillis() != null ? definition.getTimePeriodMillis() : 1000L;
044
045        // max requests per period is mandatory
046        Expression maxRequestsExpression = createMaxRequestsPerPeriodExpression(routeContext);
047        if (maxRequestsExpression == null) {
048            throw new IllegalArgumentException("MaxRequestsPerPeriod expression must be provided on " + this);
049        }
050
051        Expression correlation = null;
052        if (definition.getCorrelationExpression() != null) {
053            correlation = definition.getCorrelationExpression().createExpression(routeContext);
054        }
055
056        boolean reject = definition.getRejectExecution() != null && definition.getRejectExecution();
057        Throttler answer = new Throttler(routeContext.getCamelContext(), maxRequestsExpression, period, threadPool, shutdownThreadPool, reject, correlation);
058
059        answer.setAsyncDelayed(async);
060        if (definition.getCallerRunsWhenRejected() == null) {
061            // should be true by default
062            answer.setCallerRunsWhenRejected(true);
063        } else {
064            answer.setCallerRunsWhenRejected(definition.getCallerRunsWhenRejected());
065        }
066
067        return answer;
068    }
069
070    private Expression createMaxRequestsPerPeriodExpression(RouteContext routeContext) {
071        ExpressionDefinition expr = definition.getExpression();
072        if (expr != null) {
073            return expr.createExpression(routeContext);
074        }
075        return null;
076    }
077
078}