| /* |
| * Copyright (c) 2004, 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.misc.Perf; |
| import sun.jvmstat.monitor.*; |
| import java.util.*; |
| import java.io.*; |
| import java.lang.reflect.*; |
| import java.nio.ByteBuffer; |
| |
| /** |
| * Abstraction for the HotSpot PerfData instrumentation buffer. This class |
| * is responsible for acquiring access to the instrumentation buffer for |
| * a target HotSpot Java Virtual Machine and providing method level access |
| * to its contents. |
| * |
| * @author Brian Doherty |
| * @since 1.5 |
| */ |
| public abstract class AbstractPerfDataBuffer { |
| |
| /** |
| * Reference to the concrete instance created by the |
| * {@link #createPerfDataBuffer} method. |
| */ |
| protected PerfDataBufferImpl impl; |
| |
| /** |
| * Get the Local Java Virtual Machine Identifier, or <em>lvmid</em> |
| * for the target JVM associated with this instrumentation buffer. |
| * |
| * @return int - the lvmid |
| */ |
| public int getLocalVmId() { |
| return impl.getLocalVmId(); |
| } |
| |
| /** |
| * 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() { |
| return impl.getBytes(); |
| } |
| |
| /** |
| * Get the capacity of the instrumentation buffer. |
| * |
| * @return int - the capacity, or size, of the instrumentation buffer. |
| */ |
| public int getCapacity() { |
| return impl.getCapacity(); |
| } |
| |
| /** |
| * 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 |
| * <tt>null</tt>. |
| * |
| * @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 |
| * <tt>null</tt> 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 { |
| return impl.findByName(name); |
| } |
| |
| /** |
| * 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<Monitor> - 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<Monitor> findByPattern(String patternString) throws MonitorException { |
| return impl.findByPattern(patternString); |
| } |
| |
| /** |
| * 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 { |
| return impl.getMonitorStatus(); |
| } |
| |
| /** |
| * Get the ByteBuffer containing the instrumentation data. |
| * |
| * @return ByteBuffer - a ByteBuffer object that refers to the |
| * instrumentation data. |
| */ |
| public ByteBuffer getByteBuffer() { |
| return impl.getByteBuffer(); |
| } |
| |
| /** |
| * Create the perfdata instrumentation buffer for the given lvmid |
| * using the given ByteBuffer object as the source of the instrumentation |
| * data. This method parses the instrumentation buffer header to determine |
| * key characteristics of the instrumentation buffer and then dynamically |
| * loads the appropriate class to handle the particular instrumentation |
| * version. |
| * |
| * @param bb the ByteBuffer that references the instrumentation data. |
| * @param lvmid the Local Java Virtual Machine identifier for this |
| * instrumentation buffer. |
| * |
| * @throws MonitorException |
| */ |
| protected void createPerfDataBuffer(ByteBuffer bb, int lvmid) |
| throws MonitorException { |
| int majorVersion = AbstractPerfDataBufferPrologue.getMajorVersion(bb); |
| int minorVersion = AbstractPerfDataBufferPrologue.getMinorVersion(bb); |
| |
| // instantiate the version specific class |
| String classname = "sun.jvmstat.perfdata.monitor.v" |
| + majorVersion + "_" + minorVersion |
| + ".PerfDataBuffer"; |
| |
| try { |
| Class<?> implClass = Class.forName(classname); |
| Constructor cons = implClass.getConstructor(new Class[] { |
| Class.forName("java.nio.ByteBuffer"), |
| Integer.TYPE |
| }); |
| |
| impl = (PerfDataBufferImpl)cons.newInstance(new Object[] { |
| bb, new Integer(lvmid) |
| }); |
| |
| } catch (ClassNotFoundException e) { |
| // from Class.forName(); |
| throw new IllegalArgumentException( |
| "Could not find " + classname + ": " + e.getMessage(), e); |
| |
| } catch (NoSuchMethodException e) { |
| // from Class.getConstructor(); |
| throw new IllegalArgumentException( |
| "Expected constructor missing in " + classname + ": " |
| + e.getMessage(), e); |
| |
| } catch (IllegalAccessException e) { |
| // from Constructor.newInstance() |
| throw new IllegalArgumentException( |
| "Unexpected constructor access in " + classname + ": " |
| + e.getMessage(), e); |
| |
| } catch (InstantiationException e) { |
| throw new IllegalArgumentException( |
| classname + "is abstract: " + e.getMessage(), e); |
| |
| } catch (InvocationTargetException e) { |
| Throwable cause = e.getCause(); |
| if (cause instanceof MonitorException) { |
| throw (MonitorException)cause; |
| } |
| throw new RuntimeException("Unexpected exception: " |
| + e.getMessage() , e); |
| } |
| } |
| } |
