/* * Copyright (c) 2004, 2014, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. Oracle designates this * particular file as subject to the "Classpath" exception as provided * by Oracle in the LICENSE file that accompanied this code. * * This code 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 * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */ package sun.jvmstat.perfdata.monitor; import sun.jvmstat.monitor.*; import java.util.*; import java.nio.*; import java.io.*; import java.net.*; import java.util.regex.*; /** * The base classes for the concrete implementations of the HotSpot * PerfData instrumentation buffer. * * @author Brian Doherty * @since 1.5 * @see AbstractPerfDataBuffer */ public abstract class PerfDataBufferImpl { /** * The buffer containing the instrumentation data. */ protected ByteBuffer buffer; /** * A Map of monitor objects found in the instrumentation buffer. */ protected Map monitors; /** * The Local Java Virtual Machine Identifier for this buffer. */ protected int lvmid; /** * A Map of monitor object names to aliases as read in from the alias map * file. */ protected Map> aliasMap; /** * A cache of resolved monitor aliases. */ protected Map aliasCache; /** * Constructor. * * @param buffer the ByteBuffer containing the instrumentation data. * @param lvmid the Local Java Virtual Machine Identifier for this * instrumentation buffer. */ protected PerfDataBufferImpl(ByteBuffer buffer, int lvmid) { this.buffer = buffer; this.lvmid = lvmid; this.monitors = new TreeMap(); this.aliasMap = new HashMap>(); this.aliasCache = new HashMap(); } /** * Get the Local Java Virtual Machine Identifier, or lvmid * for the target JVM associated with this instrumentation buffer. * * @return int - the lvmid */ public int getLocalVmId() { return lvmid; } /** * Get a copy of the raw instrumentation data. * This method is used to get a copy of the current bytes in the * instrumentation buffer. It is generally used for transporting * those bytes over the network. * * @return byte[] - a copy of the bytes in the instrumentation buffer. */ public byte[] getBytes() { ByteBuffer bb = null; synchronized (this) { /* * this operation is potentially time consuming, and the result * is unused when the getBytes() interface is used. However, the * call is necessary in order to synchronize this monitoring * client with the target jvm, which assures that the receiver * of the byte[] gets an image that is initialized to a usable * state. Otherwise, they might only get a snapshot of an * empty instrumentation buffer immediately after it was created. */ try { if (monitors.isEmpty()) { buildMonitorMap(monitors); } } catch (MonitorException e) { /* * just ignore this here and let the receiver of the * byte[] detect and handle the problem. */ } bb = buffer.duplicate(); } bb.rewind(); byte[] bytes = new byte[bb.limit()]; bb.get(bytes); return bytes; } /** * Get the capacity of the instrumentation buffer. * * @return int - the capacity, or size, of the instrumentation buffer. */ public int getCapacity() { return buffer.capacity(); } /** * Get the ByteBuffer containing the instrumentation data. * * @return ByteBuffer - a ByteBuffer object that refers to the * instrumentation data. */ ByteBuffer getByteBuffer() { // receiver is responsible for assuring that the buffer's state // is that of an initialized target. return buffer; } /** * Build the alias mapping. Uses the default alias map file unless * the sun.jvmstat.perfdata.aliasmap file indicates some other * file as the source. */ private void buildAliasMap() { assert Thread.holdsLock(this); URL aliasURL = null; String filename = System.getProperty("sun.jvmstat.perfdata.aliasmap"); if (filename != null) { File f = new File(filename); try { aliasURL = f.toURL(); } catch (MalformedURLException e) { throw new IllegalArgumentException(e); } } else { aliasURL = getClass().getResource( "/sun/jvmstat/perfdata/resources/aliasmap"); } assert aliasURL != null; AliasFileParser aliasParser = new AliasFileParser(aliasURL); try { aliasParser.parse(aliasMap); } catch (IOException e) { System.err.println("Error processing " + filename + ": " + e.getMessage()); } catch (SyntaxException e) { System.err.println("Syntax error parsing " + filename + ": " + e.getMessage()); } } /** * Find the Monitor object for the named counter by using one of its * aliases. */ protected Monitor findByAlias(String name) { assert Thread.holdsLock(this); Monitor m = (Monitor)aliasCache.get(name); if (m == null) { ArrayList al = aliasMap.get(name); if (al != null) { for (Iterator i = al.iterator(); i.hasNext() && m == null; ) { String alias = (String)i.next(); m = monitors.get(alias); } } } return m; } /** * Find a named Instrumentation object. * * This method will look for the named instrumentation object in the * instrumentation exported by this Java Virtual Machine. If an * instrumentation object with the given name exists, a Monitor interface * to that object will be return. Otherwise, the method returns * null. The method will map requests for instrumention objects * using old names to their current names, if applicable. * * * * @param name the name of the Instrumentation object to find. * @return Monitor - the {@link Monitor} object that can be used to * monitor the the named instrumentation object, or * null if the named object doesn't exist. * @throws MonitorException Thrown if an error occurs while communicating * with the target Java Virtual Machine. */ public Monitor findByName(String name) throws MonitorException { Monitor m = null; synchronized (this) { if (monitors.isEmpty()) { buildMonitorMap(monitors); buildAliasMap(); } // look for the requested monitor m = monitors.get(name); if (m == null) { // not found - load any new monitors, and try again. getNewMonitors(monitors); m = monitors.get(name); } if (m == null) { // still not found, look for aliases m = findByAlias(name); } } return m; } /** * Find all Instrumentation objects with names matching the given pattern. * * This method returns a {@link List} of Monitor objects such that * the name of each object matches the given pattern. * * @param patternString a string containing a pattern as described in * {@link java.util.regex.Pattern}. * @return List - a List of {@link Monitor} objects that can be used to * monitor the instrumentation objects whose names match * the given pattern. If no instrumentation objects have` * names matching the given pattern, then an empty List * is returned. * @throws MonitorException Thrown if an error occurs while communicating * with the target Java Virtual Machine. * @see java.util.regex.Pattern */ public List findByPattern(String patternString) throws MonitorException, PatternSyntaxException { synchronized(this) { if (monitors.isEmpty()) { buildMonitorMap(monitors); } else { getNewMonitors(monitors); } } Pattern pattern = Pattern.compile(patternString); Matcher matcher = pattern.matcher(""); List matches = new ArrayList(); Set monitorSet = monitors.entrySet(); for (Iterator i = monitorSet.iterator(); i.hasNext(); /* empty */) { Map.Entry me = (Map.Entry)i.next(); String name = (String)me.getKey(); Monitor m = (Monitor)me.getValue(); // apply pattern to monitor item name matcher.reset(name); // if the pattern matches, then add monitor to list if (matcher.lookingAt()) { matches.add((Monitor)me.getValue()); } } return matches; } /** * Get a list of the inserted and removed monitors since last called. * * @return MonitorStatus - the status of available Monitors for the * target Java Virtual Machine. * @throws MonitorException Thrown if communications errors occur * while communicating with the target. */ public MonitorStatus getMonitorStatus() throws MonitorException { synchronized(this) { if (monitors.isEmpty()) { buildMonitorMap(monitors); } return getMonitorStatus(monitors); } } // PerfDataBuffer implementation specific classes /** * get the list of inserted and removed monitors since last called. * * @param m the map of Monitors. * @throws MonitorException Thrown if communications errors occur * while communicating with the target. */ protected abstract MonitorStatus getMonitorStatus(Map m) throws MonitorException; /** * build the map of Monitor objects. * * @param m the map of Monitors. * @throws MonitorException Thrown if communications errors occur * while communicating with the target. */ protected abstract void buildMonitorMap(Map m) throws MonitorException; /** * get the new Monitor objects from the Map of Monitor objects. * * @param m the map of Monitors. * @throws MonitorException Thrown if communications errors occur * while communicating with the target. */ protected abstract void getNewMonitors(Map m) throws MonitorException; }