| /* |
| * 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.v1_0; |
| |
| import sun.jvmstat.monitor.*; |
| import sun.jvmstat.perfdata.monitor.*; |
| import java.nio.*; |
| |
| /** |
| * Class representing the 1.0 version of the HotSpot PerfData instrumentation |
| * buffer header. |
| * <p> |
| * The PerfDataBufferPrologue2_0 class supports parsing of the version |
| * specific portions of the PerfDataPrologue C structure: |
| * <pre> |
| * typedef struct { |
| * ... // handled by superclass |
| * jint used; // number of PerfData memory bytes used |
| * jint overflow; // number of bytes of overflow |
| * jlong mod_time_stamp; // time stamp of the last structural modification |
| * } PerfDataPrologue |
| * </pre> |
| * |
| * @author Brian Doherty |
| * @since 1.5 |
| */ |
| public class PerfDataBufferPrologue extends AbstractPerfDataBufferPrologue { |
| |
| private static final int SUPPORTED_MAJOR_VERSION = 1; |
| private static final int SUPPORTED_MINOR_VERSION = 0; |
| |
| /* |
| * the following constants must match the field offsets and sizes |
| * in the PerfDataPrologue structure in perfMemory.hpp |
| */ |
| final static int PERFDATA_PROLOG_USED_OFFSET=8; |
| final static int PERFDATA_PROLOG_USED_SIZE=4; // sizeof(int) |
| final static int PERFDATA_PROLOG_OVERFLOW_OFFSET=12; |
| final static int PERFDATA_PROLOG_OVERFLOW_SIZE=4; // sizeof(int) |
| final static int PERFDATA_PROLOG_MODTIMESTAMP_OFFSET=16; |
| final static int PERFDATA_PROLOG_MODTIMESTAMP_SIZE=8; // sizeof(long) |
| final static int PERFDATA_PROLOG_SIZE=24; // sizeof(struct PerfDataProlog) |
| |
| // counter names for prologue psuedo counters |
| final static String PERFDATA_BUFFER_SIZE_NAME = "sun.perfdata.size"; |
| final static String PERFDATA_BUFFER_USED_NAME = "sun.perfdata.used"; |
| final static String PERFDATA_OVERFLOW_NAME = "sun.perfdata.overflow"; |
| final static String PERFDATA_MODTIMESTAMP_NAME = "sun.perfdata.timestamp"; |
| |
| /** |
| * Create an instance of PerfDataBufferPrologue from the given |
| * ByteBuffer object. |
| * |
| * @param byteBuffer the buffer containing the binary header data |
| */ |
| public PerfDataBufferPrologue(ByteBuffer byteBuffer) |
| throws MonitorException { |
| super(byteBuffer); |
| assert ((getMajorVersion() == 1) && (getMinorVersion() == 0)); |
| } |
| |
| /** |
| * {@inheritDoc} |
| */ |
| public boolean supportsAccessible() { |
| return false; |
| } |
| |
| /** |
| * {@inheritDoc} |
| */ |
| public boolean isAccessible() { |
| return true; |
| } |
| |
| /** |
| * Get the utilization of the instrumentation memory buffer. |
| * |
| * @return int - the utilization of the buffer |
| */ |
| public int getUsed() { |
| byteBuffer.position(PERFDATA_PROLOG_USED_OFFSET); |
| return byteBuffer.getInt(); |
| } |
| |
| /** |
| * Get the size of the instrumentation memory buffer. |
| * |
| * @return int - the size of the buffer |
| */ |
| public int getBufferSize() { |
| return byteBuffer.capacity(); |
| } |
| |
| /** |
| * Get the buffer overflow amount. This value is non-zero if the |
| * HotSpot JVM has overflowed the instrumentation memory buffer. |
| * The target JVM can be restarted with -XX:PerfDataMemSize=X to |
| * create a larger memory buffer. |
| * |
| * @return int - the size of the buffer |
| */ |
| public int getOverflow() { |
| byteBuffer.position(PERFDATA_PROLOG_OVERFLOW_OFFSET); |
| return byteBuffer.getInt(); |
| } |
| |
| /** |
| * Get the time of last modification for the instrumentation |
| * memory buffer. This method returns the time, as ticks since the |
| * start of the target JVM, of the last structural modification to |
| * the instrumentation buffer. Structural modifications correspond to |
| * the addition or deletion of instrumentation objects. Updates to |
| * counter values are not structural modifications. |
| */ |
| public long getModificationTimeStamp() { |
| byteBuffer.position(PERFDATA_PROLOG_MODTIMESTAMP_OFFSET); |
| return byteBuffer.getLong(); |
| } |
| |
| /** |
| * {@inheritDoc} |
| */ |
| public int getSize() { |
| return PERFDATA_PROLOG_SIZE; // sizeof(struct PerfDataProlog) |
| } |
| |
| /** |
| * Return an IntBuffer that accesses the used value. This is used |
| * to create a Monitor object for this value. |
| * |
| * @return IntBuffer - a ByteBuffer that accesses the used value |
| * in the instrumentation buffer header. |
| * @see #getUsed() |
| */ |
| public IntBuffer usedBuffer() { |
| byteBuffer.position(PERFDATA_PROLOG_USED_OFFSET); |
| IntBuffer ib = byteBuffer.asIntBuffer(); |
| ib.limit(1); |
| return ib; |
| } |
| |
| /** |
| * Return an IntBuffer that accesses the size value. This is used |
| * to create a Monitor object for this value. |
| * |
| * @return IntBuffer - a ByteBuffer that accesses the size value |
| * in the instrumentation buffer header. |
| * @see #getBufferSize() |
| */ |
| public IntBuffer sizeBuffer() { |
| IntBuffer ib = IntBuffer.allocate(1); |
| ib.put(byteBuffer.capacity()); |
| return ib; |
| } |
| |
| /** |
| * Return an IntBuffer that accesses the overflow value. This is used |
| * to create a Monitor object for this value. |
| * |
| * @return IntBuffer - a ByteBuffer that accesses the overflow value |
| * in the instrumentation buffer header. |
| * @see #getOverflow() |
| */ |
| public IntBuffer overflowBuffer() { |
| byteBuffer.position(PERFDATA_PROLOG_OVERFLOW_OFFSET); |
| IntBuffer ib = byteBuffer.asIntBuffer(); |
| ib.limit(1); |
| return ib; |
| } |
| |
| /** |
| * Return an LongBuffer that accesses the modification timestamp value. |
| * This is used* to create a Monitor object for this value. |
| * |
| * @return LongBuffer - a ByteBuffer that accesses the modification time |
| * stamp value in the instrumentation buffer header. |
| * @see #getModificationTimeStamp() |
| */ |
| public LongBuffer modificationTimeStampBuffer() { |
| byteBuffer.position(PERFDATA_PROLOG_MODTIMESTAMP_OFFSET); |
| LongBuffer lb = byteBuffer.asLongBuffer(); |
| lb.limit(1); |
| return lb; |
| } |
| } |