Java tutorial
/* * NOTE: This copyright does *not* cover user programs that use HQ * program services by normal system calls through the application * program interfaces provided as part of the Hyperic Plug-in Development * Kit or the Hyperic Client Development Kit - this is merely considered * normal use of the program, and does *not* fall under the heading of * "derived work". * * Copyright (C) [2004, 2005, 2006], Hyperic, Inc. * This file is part of HQ. * * HQ is free software; you can redistribute it and/or modify * it under the terms version 2 of the GNU General Public License as * published by the Free Software Foundation. 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 * USA. */ package org.hyperic.hq.plugin.postgresql; import java.sql.Connection; import java.sql.DriverManager; import java.sql.ResultSet; import java.sql.SQLException; import java.sql.Statement; import java.util.Properties; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.hyperic.hq.product.Collector; import org.hyperic.hq.product.Metric; import org.hyperic.hq.product.MetricNotFoundException; import org.hyperic.hq.product.MetricUnreachableException; import org.hyperic.hq.product.MetricValue; import org.hyperic.hq.product.PluginException; import org.hyperic.hq.product.SigarMeasurementPlugin; import org.hyperic.sigar.Sigar; import org.hyperic.sigar.SigarException; import org.hyperic.sigar.SigarNotImplementedException; import org.hyperic.sigar.SigarProxy; import org.hyperic.sigar.SigarProxyCache; import org.hyperic.sigar.jmx.SigarInvokerJMX; import org.hyperic.util.jdbc.DBUtil; public class ServerMeasurement extends SigarMeasurementPlugin { private Log log = LogFactory.getLog(ServerMeasurement.class); private long pid = -1; private Sigar sigar = null; private SigarProxy sigarProxy = null; private String actualConfig = ""; @Override public MetricValue getValue(Metric metric) throws PluginException, MetricNotFoundException, MetricUnreachableException { if (metric.getDomainName().equals("collector")) { return Collector.getValue(this, metric); } MetricValue res; initSigar(); try { findPid(metric); } catch (PluginException ex) { if (metric.isAvail()) { log.debug(ex, ex); return new MetricValue(Metric.AVAIL_DOWN); } else { throw ex; } } if (metric.isAvail()) { res = new MetricValue(Metric.AVAIL_UP); } else { String oName = "sigar:Type=" + metric.getObjectProperty("Type") + ",Arg=State.Ppid.eq=" + pid; log.debug("[getValue] oName=" + oName); String attr = metric.getAttributeName(); SigarInvokerJMX invoker = SigarInvokerJMX.getInstance(this.sigarProxy, oName); try { Object systemValue; synchronized (this.sigar) { systemValue = invoker.invoke(attr); } if (systemValue instanceof Double) { res = new MetricValue((Double) systemValue); } else if (systemValue instanceof Long) { res = new MetricValue(new Double(((Long) systemValue).longValue())); } else if (systemValue instanceof Integer) { res = new MetricValue(new Double(((Integer) systemValue).intValue())); } else { PluginException ex = new PluginException( "Error on systemValue '" + systemValue + "' (" + systemValue.getClass() + ")"); log.debug(ex, ex); throw ex; } } catch (SigarNotImplementedException e) { pid = -1; throw new MetricUnreachableException(e.getMessage(), e); } catch (SigarException e) { pid = -1; throw new MetricNotFoundException(e.getMessage(), e); } } return res; } protected void initSigar() throws PluginException { if (this.sigar == null) { try { this.sigar = new Sigar(); this.sigarProxy = SigarProxyCache.newInstance(sigar); } catch (UnsatisfiedLinkError ex) { log.debug("unable to load sigar: " + ex.getMessage(), ex); this.sigar = null; this.sigarProxy = null; throw new PluginException(ex.getMessage(), ex); } } } private void findPid(Metric metric) throws PluginException { Properties props = metric.getProperties(); String user = props.getProperty(PostgreSQL.PROP_USER); String pass = props.getProperty(PostgreSQL.PROP_PASS); String url = PostgreSQL.prepareUrl(props, null); String newConfig = url + "-" + user + "-" + pass; boolean isNewConfig = !newConfig.equalsIgnoreCase(actualConfig); if (isNewConfig) { log.debug("[findPid] new config detected"); actualConfig = newConfig; } // look for the PID // IF config have changed (to test is the new config is valid) // OR no PID // OR always for Availability if (isNewConfig || (pid == -1) || (metric.isAvail())) { Connection conn = null; Statement stmt = null; ResultSet rs = null; try { conn = DriverManager.getConnection(url, user, pass); stmt = conn.createStatement(); stmt.execute("select pg_backend_pid()"); rs = stmt.getResultSet(); if (rs.next()) { int conectionPid = rs.getInt(1); pid = new Sigar().getProcState(conectionPid).getPpid(); log.debug("[findPid] conection PID:" + conectionPid + " ==> main Process PID:" + pid); } } catch (SQLException ex) { pid = -1; throw new PluginException(ex.getMessage(), ex); } catch (SigarException ex) { pid = -1; throw new PluginException(ex.getMessage(), ex); } finally { DBUtil.closeJDBCObjects(getLog(), conn, stmt, rs); } } } }