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ActiveMQ example source code file (AMQIterator.java)
The ActiveMQ AMQIterator.java source code/** * 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.activemq.console.command.store.amq.reader; import java.util.Iterator; import javax.jms.InvalidSelectorException; import javax.jms.Message; import org.apache.activemq.broker.region.MessageReference; import org.apache.activemq.filter.BooleanExpression; import org.apache.activemq.filter.MessageEvaluationContext; import org.apache.activemq.selector.SelectorParser; /** * An Iterator for the AMQReader * */ class AMQIterator implements Iterator<Message>{ private AMQReader reader; private BooleanExpression expression; private MessageLocation currentLocation; private MessageLocation nextLocation; private boolean valid=true; AMQIterator(AMQReader reader, BooleanExpression expression){ this.reader=reader; this.expression=expression; } public boolean hasNext() { try { this.nextLocation = reader.getNextMessage(currentLocation); Message next = nextLocation != null ? nextLocation.getMessage() : null; if (expression == null) { return next != null; } else { while (next != null) { MessageEvaluationContext context = new MessageEvaluationContext(); context.setMessageReference((MessageReference) next); if (expression.matches(context)) { return true; } this.nextLocation = reader.getNextMessage(currentLocation); next = nextLocation != null ? nextLocation.getMessage() : null; } valid=false; return false; } } catch (Exception e) { throw new RuntimeException( "Failed to get next message from reader ", e); } } public Message next() { if (valid && (nextLocation != null || hasNext())) { this.currentLocation=nextLocation; return nextLocation.getMessage(); } return null; } public void remove() { throw new IllegalStateException("Not supported"); } } Other ActiveMQ examples (source code examples)Here is a short list of links related to this ActiveMQ AMQIterator.java source code file: |
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