1/* 2 * Copyright (c) 2004, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. Oracle designates this 8 * particular file as subject to the "Classpath" exception as provided 9 * by Oracle in the LICENSE file that accompanied this code. 10 * 11 * This code is distributed in the hope that it will be useful, but WITHOUT 12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 14 * version 2 for more details (a copy is included in the LICENSE file that 15 * accompanied this code). 16 * 17 * You should have received a copy of the GNU General Public License version 18 * 2 along with this work; if not, write to the Free Software Foundation, 19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 20 * 21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 22 * or visit www.oracle.com if you need additional information or have any 23 * questions. 24 */ 25 26package sun.jvmstat.perfdata.monitor.protocol.local; 27 28import jdk.internal.perf.Perf; 29import sun.jvmstat.monitor.*; 30import sun.jvmstat.perfdata.monitor.*; 31import java.util.*; 32import java.io.*; 33import java.nio.ByteBuffer; 34import java.nio.channels.FileChannel; 35import java.lang.reflect.Constructor; 36import java.security.AccessController; 37 38/** 39 * The concrete PerfDataBuffer implementation for the <em>local:</em> 40 * protocol for the HotSpot PerfData monitoring implementation. 41 * <p> 42 * This class is responsible for acquiring access to the shared memory 43 * instrumentation buffer for the target HotSpot Java Virtual Machine. 44 * 45 * @author Brian Doherty 46 * @since 1.5 47 */ 48// Suppreess unchecked conversion warning at line 34. 49//@SuppressWarnings("unchecked") 50public class PerfDataBuffer extends AbstractPerfDataBuffer { 51 private static final Perf perf = AccessController.doPrivileged(new Perf.GetPerfAction()); 52 53 /** 54 * Create a PerfDataBuffer instance for accessing the specified 55 * instrumentation buffer. 56 * 57 * @param vmid the <em>local:</em> URI specifying the target JVM. 58 * 59 * @throws MonitorException 60 */ 61 public PerfDataBuffer(VmIdentifier vmid) throws MonitorException { 62 try { 63 // Try 1.4.2 and later first 64 ByteBuffer bb = perf.attach(vmid.getLocalVmId(), vmid.getMode()); 65 createPerfDataBuffer(bb, vmid.getLocalVmId()); 66 67 } catch (IllegalArgumentException e) { 68 // now try 1.4.1 by attempting to directly map the files. 69 try { 70 String filename = PerfDataFile.getTempDirectory() 71 + PerfDataFile.dirNamePrefix 72 + Integer.toString(vmid.getLocalVmId()); 73 74 File f = new File(filename); 75 76 FileChannel fc = new RandomAccessFile(f, "r").getChannel(); 77 ByteBuffer bb = fc.map(FileChannel.MapMode.READ_ONLY, 0L, 78 (int)fc.size()); 79 fc.close(); 80 createPerfDataBuffer(bb, vmid.getLocalVmId()); 81 82 } catch (FileNotFoundException e2) { 83 // re-throw the exception from the 1.4.2 attach method 84 throw new MonitorException(vmid.getLocalVmId() + " not found", 85 e); 86 } catch (IOException e2) { 87 throw new MonitorException("Could not map 1.4.1 file for " 88 + vmid.getLocalVmId(), e2); 89 } 90 } catch (IOException e) { 91 throw new MonitorException("Could not attach to " 92 + vmid.getLocalVmId(), e); 93 } 94 } 95} 96