Java tutorial
/******************************************************************************* * This file is part of OpenNMS(R). * * Copyright (C) 2002-2014 The OpenNMS Group, Inc. * OpenNMS(R) is Copyright (C) 1999-2014 The OpenNMS Group, Inc. * * OpenNMS(R) is a registered trademark of The OpenNMS Group, Inc. * * OpenNMS(R) is free software: you can redistribute it and/or modify * it under the terms of the GNU Affero General Public License as published * by the Free Software Foundation, either version 3 of the License, * or (at your option) any later version. * * OpenNMS(R) is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU Affero General Public License for more details. * * You should have received a copy of the GNU Affero General Public License * along with OpenNMS(R). If not, see: * http://www.gnu.org/licenses/ * * For more information contact: * OpenNMS(R) Licensing <license@opennms.org> * http://www.opennms.org/ * http://www.opennms.com/ *******************************************************************************/ package org.opennms.netmgt.model.discovery; import java.io.Serializable; import java.net.InetAddress; import java.util.Enumeration; import java.util.Iterator; import org.apache.commons.lang.builder.ToStringBuilder; /** * <p> * This class is designed to encapsulate the information about an address range * plus the retry & timeout information. The class is designed so that it * can return either an {@link java.util.Enumeration enumeration}or an * {@link java.util.Iterator iterator}to traverse the range of addresses. * </p> * * @author <A HREF="mailto:sowmya@opennms.org">Sowmya </A> * @author <A HREF="mailto:weave@oculan.com">Brian Weaver </A> */ public class IPPollRange implements Iterable<IPPollAddress>, Serializable { private static final long serialVersionUID = -287583115922481242L; /** * The range to cycle over. */ private final IPAddrRange m_range; private final String m_foreignSource; private final String m_location; /** * The timeout in milliseconds (1/1000th) */ private final long m_timeout; /** * The number of retries for each generate object. */ private final int m_retries; /** * <P> * The purpose of the IPPollRangeGenerator class is to provide an * Enumeration or Iterator object that can be returned by the encapsulating * class. The class implements the new style Iterator interface, as well as * the old style Enumeration to allow the developer freedom of choice when * cycling over ranges. * </P> * * @see java.util.Iterator * @see java.util.Enumeration */ final class IPPollRangeGenerator implements Enumeration<IPPollAddress>, Iterator<IPPollAddress> { /** * <P> * The range of address to generate. * </P> */ private Enumeration<InetAddress> m_range; /** * <P> * Creates a poll range generator object. * </P> * * @param en * The Enumeration to use for address generation. */ public IPPollRangeGenerator(Enumeration<InetAddress> en) { m_range = en; } /** * <P> * Returns true if the Enumeration described by this object still has * more elements. * </P> */ @Override public boolean hasMoreElements() { return m_range.hasMoreElements(); } /** * <P> * Returns the next IPPollAddress in the enumeration. * </P> * * @exception java.util.NoSuchElementException * Thrown if there are no more elements in the iteration. */ @Override public IPPollAddress nextElement() { return new IPPollAddress(m_foreignSource, m_location, (InetAddress) m_range.nextElement(), m_timeout, m_retries); } /** * <P> * If there are more elements left in the iteration then a value of true * is returned. Else a false value is returned. * </P> */ @Override public boolean hasNext() { return hasMoreElements(); } /** * <P> * Returns the next object in the iteration and increments the internal * pointer. * </P> * * @exception java.util.NoSuchElementException * Thrown if there are no more elements in the iteration. */ @Override public IPPollAddress next() { return nextElement(); } /** * The remove method is part of the Iterator interface and is optional. * Since it is not implemnted it will always throw an * UnsupportedOperationException. * * @exception java.lang.UnsupportedOperationException * Always thrown by this method. */ @Override public void remove() { throw new UnsupportedOperationException("remove operation not supported"); } } // end IPPollRangeGenerator /** * <P> * Creates an IPPollRange object that can be used to generate IPPollAddress * objects. The addresses are encapsulated by the range object and the * values of timeout and retry are set in each generated IPPollAddress * object. * </P> * * @param fromIP * The start of the address range to cycle over. * @param toIP * The end of the address range to cycle over. * @param timeout * The timeout for each generated IPPollAddress. * @param retries * The number of retries for generated addresses. * @see IPPollAddress * @see IPAddrRange * @throws java.net.UnknownHostException if any. */ public IPPollRange(String foreignSource, String location, String fromIP, String toIP, long timeout, int retries) throws java.net.UnknownHostException { m_range = new IPAddrRange(fromIP, toIP); m_foreignSource = foreignSource; m_location = location; m_timeout = timeout; m_retries = retries; } /** * <P> * Creates an IPPollRange object that can be used to generate IPPollAddress * objects. The addresses are encapsulated by the range [start..end] and the * values of timeout and retry are set in each generated IPPollAddress * object. * </P> * * @param start * The start of the address range to cycle over. * @param end * The end of the address range to cycle over. * @param timeout * The timeout for each generated IPPollAddress. * @param retries * The number of retries for generated addresses. * * @see IPPollAddress * @see IPAddrRange * */ public IPPollRange(String foreignSource, String location, InetAddress start, InetAddress end, long timeout, int retries) { this(foreignSource, location, new IPAddrRange(start, end), timeout, retries); } /** * <P> * Creates an IPPollRange object that can be used to generate IPPollAddress * objects. The addresses are encapsulated by the range object and the * values of timeout and retry are set in each generated IPPollAddress * object. * </P> * * @param range * The address range to cycle over. * @param timeout * The timeout for each generated IPPollAddress. * @param retries * The number of retries for generated addresses. * * @see IPPollAddress * */ IPPollRange(String foreignSource, String location, IPAddrRange range, long timeout, int retries) { m_range = range; m_foreignSource = foreignSource; m_location = location; m_timeout = timeout; m_retries = retries; } /** * Foreign source where this address should be persisted. */ public String getForeignSource() { return m_foreignSource; } /** * Network location of this address. */ public String getLocation() { return m_location; } /** * <P> * Returns the timeout set for the object. The timeout should be in 1/1000th * of a second increments. * </P> * * @return a long. */ public long getTimeout() { return m_timeout; } /** * <P> * Returns the retry count for the object. * </P> * * @return a int. */ public int getRetries() { return m_retries; } /** * <P> * Returns the configured address ranges that are encapsulated by this * object. * </P> * * @return a {@link org.opennms.netmgt.model.discovery.IPAddrRange} object. */ public IPAddrRange getAddressRange() { return m_range; } /** * <P> * Returns an Enumeration that can be used to cycle over the range of * pollable addresses. * </P> * * @return a {@link java.util.Enumeration} object. */ public Enumeration<IPPollAddress> elements() { return new IPPollRangeGenerator(m_range.elements()); } /** * <P> * Returns an Iterator object that can be used to cycle over the range of * pollable address information. * </P> * * @return a {@link java.util.Iterator} object. */ @Override public Iterator<IPPollAddress> iterator() { return new IPPollRangeGenerator(m_range.elements()); } @Override public String toString() { return new ToStringBuilder(this).append("foreignSource", m_foreignSource).append("location", m_location) .append("range", m_range).append("timeout", m_timeout).append("retries", m_retries).toString(); } }