J. Duke | 319a3b9 | 2007-12-01 00:00:00 +0000 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright 2004 Sun Microsystems, Inc. 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. Sun designates this |
| 8 | * particular file as subject to the "Classpath" exception as provided |
| 9 | * by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, |
| 22 | * CA 95054 USA or visit www.sun.com if you need additional information or |
| 23 | * have any questions. |
| 24 | */ |
| 25 | |
| 26 | package sun.jvmstat.perfdata.monitor.protocol.file; |
| 27 | |
| 28 | import sun.jvmstat.monitor.*; |
| 29 | import sun.jvmstat.perfdata.monitor.*; |
| 30 | import java.io.*; |
| 31 | import java.net.URI; |
| 32 | import java.nio.ByteBuffer; |
| 33 | import java.nio.channels.FileChannel; |
| 34 | |
| 35 | /** |
| 36 | * The concrete PerfDataBuffer implementation for the <em>file:</em> |
| 37 | * protocol for the HotSpot PerfData monitoring implemetation. |
| 38 | * <p> |
| 39 | * This class is responsible for acquiring access to the instrumentation |
| 40 | * buffer stored in a file referenced by a file URI. |
| 41 | * |
| 42 | * @author Brian Doherty |
| 43 | * @since 1.5 |
| 44 | */ |
| 45 | public class PerfDataBuffer extends AbstractPerfDataBuffer { |
| 46 | |
| 47 | /** |
| 48 | * Create a PerfDataBuffer instance for accessing the specified |
| 49 | * instrumentation buffer. |
| 50 | * |
| 51 | * @param vmid the <em>file:</em> URI to the instrumentation buffer file |
| 52 | * |
| 53 | * @throws MonitorException |
| 54 | */ |
| 55 | public PerfDataBuffer(VmIdentifier vmid) throws MonitorException { |
| 56 | File f = new File(vmid.getURI()); |
| 57 | String mode = vmid.getMode(); |
| 58 | |
| 59 | try { |
| 60 | FileChannel fc = new RandomAccessFile(f, mode).getChannel(); |
| 61 | ByteBuffer bb = null; |
| 62 | |
| 63 | if (mode.compareTo("r") == 0) { |
| 64 | bb = fc.map(FileChannel.MapMode.READ_ONLY, 0L, (int)fc.size()); |
| 65 | } else if (mode.compareTo("rw") == 0) { |
| 66 | bb = fc.map(FileChannel.MapMode.READ_WRITE, 0L, (int)fc.size()); |
| 67 | } else { |
| 68 | throw new IllegalArgumentException("Invalid mode: " + mode); |
| 69 | } |
| 70 | |
| 71 | fc.close(); // doesn't need to remain open |
| 72 | |
| 73 | createPerfDataBuffer(bb, 0); |
| 74 | } catch (FileNotFoundException e) { |
| 75 | throw new MonitorException("Could not find " + vmid.toString()); |
| 76 | } catch (IOException e) { |
| 77 | throw new MonitorException("Could not read " + vmid.toString()); |
| 78 | } |
| 79 | } |
| 80 | } |