Java tutorial
/* * RHQ Management Platform * Copyright (C) 2005-2008 Red Hat, Inc. * All rights reserved. * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation version 2 of the License. * * This program 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 General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ package org.rhq.plugins.www.snmp; import java.util.Calendar; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.snmp4j.smi.OID; import org.snmp4j.smi.OctetString; import org.snmp4j.smi.SMIConstants; import org.snmp4j.smi.Variable; import org.snmp4j.smi.VariableBinding; public class SNMPValue { private final Log log = LogFactory.getLog(this.getClass()); public enum Type { LONG, STRING, LONG_CONVERTABLE } private OID oid; private Variable var; SNMPValue(VariableBinding varBinding) { this.oid = varBinding.getOid(); this.var = varBinding.getVariable(); } private String toHex(int val) { return Integer.toHexString(val & 0xff); } //from SNMPv2-TC: //PhysAddress ::= TEXTUAL-CONVENTION //DISPLAY-HINT "1x:" //STATUS current //DESCRIPTION // "Represents media- or physical-level addresses." //SYNTAX OCTET STRING public String toPhysAddressString() { byte[] data = ((OctetString) this.var).getValue(); if (data.length == 0) { return "0:0:0:0:0:0"; //e.g. loopback } StringBuilder buffer = new StringBuilder(); buffer.append(toHex(data[0])); for (int i = 1; i < data.length; i++) { buffer.append(':').append(toHex(data[i])); } return buffer.toString(); } public String getOID() { return this.oid.toString(); } public Type getType() { switch (this.var.getSyntax()) { case SMIConstants.SYNTAX_INTEGER32: case SMIConstants.SYNTAX_COUNTER32: case SMIConstants.SYNTAX_COUNTER64: case SMIConstants.SYNTAX_TIMETICKS: case SMIConstants.SYNTAX_GAUGE32: { return Type.LONG; } case SMIConstants.SYNTAX_OCTET_STRING: //XXX while we are able to convert long //does not mean we should. treat as a string //for now. //return Type.LONG_CONVERTABLE; default: { return Type.STRING; } } } /** * @return The value of the variable as a long * * @throws SNMPException If the variable cannot be expressed as a long. */ public long toLong() throws SNMPException { if (this.var.getSyntax() == SMIConstants.SYNTAX_OCTET_STRING) { return convertDateTimeOctetStringToLong(); } else { try { return this.var.toLong(); } catch (UnsupportedOperationException e) { String msg = "Cannot convert " + this.var.getSyntaxString() + " to long"; throw new SNMPException(msg); } } } @Override public boolean equals(Object obj) { if (obj instanceof SNMPValue) { Variable var = ((SNMPValue) obj).var; return (var != null) && var.equals(this.var); } return false; } @Override public int hashCode() { return ((var != null) ? var.hashCode() : 0); } @Override public String toString() { return this.var.toString(); } // XXX A bit of a hack - if it is an OctetString, treat // it like a DateAndTime (from the SNMPv2-TC MIB) private long convertDateTimeOctetStringToLong() throws SNMPException { byte[] bytes = ((OctetString) this.var).getValue(); if (bytes.length != 8) { throw new SNMPException("OctetString is not in DateAndTime syntax."); } Calendar cal = Calendar.getInstance(); int ix = 0; int year = (bytes[ix] > 0) ? bytes[ix] : (256 + bytes[ix]); year <<= 8; ix++; year += (bytes[ix] > 0) ? bytes[ix] : (256 + bytes[ix]); ix++; int month = bytes[ix++]; int day = bytes[ix++]; int hour = bytes[ix++]; int minutes = bytes[ix++]; int seconds = bytes[ix++]; int deciseconds = bytes[ix++]; cal.set(Calendar.YEAR, year); cal.set(Calendar.MONTH, (month - 1)); cal.set(Calendar.DAY_OF_MONTH, day); cal.set(Calendar.HOUR_OF_DAY, hour); cal.set(Calendar.MINUTE, minutes); cal.set(Calendar.SECOND, seconds); cal.set(Calendar.MILLISECOND, (100 * deciseconds)); cal.set(Calendar.ZONE_OFFSET, 0); cal.set(Calendar.DST_OFFSET, 0); if (log.isDebugEnabled()) { log.debug("converted to DateAndTime: millis=" + cal.getTimeInMillis() + ", date=" + cal.getTime()); } return cal.getTimeInMillis(); } }