Top Description Fields Constructors Methods
sun.jvmstat.perfdata.monitor.v2_0

public Class PerfDataBufferPrologue

extends AbstractPerfDataBufferPrologue
Class Inheritance
Imports
sun.jvmstat.monitor.*, sun.jvmstat.perfdata.monitor.*, java.nio.*
Class representing the 2.0 version of the HotSpot PerfData instrumentation buffer header.

The PerfDataBufferPrologue class supports parsing of the version specific portions of the PerfDataPrologue C structure: 

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
  jint entry_offset;       // offset of the first PerfDataEntry
  jint num_entries;        // number of allocated PerfData entries
} PerfDataPrologue
Author
Brian Doherty
Since
1.5

Field Summary

Modifier and TypeField and Description
pack-priv static final String
PERFDATA_BUFFER_SIZE_NAME

pack-priv static final String
PERFDATA_BUFFER_USED_NAME

pack-priv static final String
PERFDATA_MODTIMESTAMP_NAME

pack-priv static final String
PERFDATA_NUMENTRIES_NAME

pack-priv static final String
PERFDATA_OVERFLOW_NAME

pack-priv static final int
PERFDATA_PROLOG_ACCESSIBLE_OFFSET

pack-priv static final int
PERFDATA_PROLOG_ACCESSIBLE_SIZE

pack-priv static final int
PERFDATA_PROLOG_ENTRYOFFSET_OFFSET

pack-priv static final int
PERFDATA_PROLOG_ENTRYOFFSET_SIZE

pack-priv static final int
PERFDATA_PROLOG_MODTIMESTAMP_OFFSET

pack-priv static final int
PERFDATA_PROLOG_MODTIMESTAMP_SIZE

pack-priv static final int
PERFDATA_PROLOG_NUMENTRIES_OFFSET

pack-priv static final int
PERFDATA_PROLOG_NUMENTRIES_SIZE

pack-priv static final int
PERFDATA_PROLOG_OVERFLOW_OFFSET

pack-priv static final int
PERFDATA_PROLOG_OVERFLOW_SIZE

pack-priv static final int
PERFDATA_PROLOG_SIZE

Hides sun.jvmstat.perfdata.monitor.AbstractPerfDataBufferPrologue.PERFDATA_PROLOG_SIZE.

pack-priv static final int
PERFDATA_PROLOG_USED_OFFSET

pack-priv static final int
PERFDATA_PROLOG_USED_SIZE

private static final int
SUPPORTED_MAJOR_VERSION

private static final int
SUPPORTED_MINOR_VERSION

Inherited from sun.jvmstat.perfdata.monitor.AbstractPerfDataBufferPrologue:
byteBufferPERFDATA_MAJOR_NAMEPERFDATA_MINOR_NAME

Constructor Summary

AccessConstructor and Description
public
PerfDataBufferPrologue(ByteBuffer
the buffer containing the binary header data
byteBuffer)

Create an instance of PerfDataBufferPrologue from the given ByteBuffer object.

Method Summary

Modifier and TypeMethod and Description
public int

Returns:

int - the size of the buffer
getBufferSize()

Get the size of the instrumentation memory buffer.

public int
getEntryOffset()

Get the offset of the first PerfDataEntry.

public long
getModificationTimeStamp()

Get the time of last modification for the instrumentation memory buffer.

public int
getNumEntries()

Get the offset of the first PerfDataEntry.

public int

Returns:

int - the size of the buffer
getOverflow()

Get the buffer overflow amount.

public int
getSize()

Overrides sun.jvmstat.perfdata.monitor.AbstractPerfDataBufferPrologue.getSize.

Get the size of the header portion of the instrumentation buffer.

public int

Returns:

int - the utilization of the buffer
getUsed()

Get the utilization of the instrumentation memory buffer.

public boolean
isAccessible()

Implements abstract sun.jvmstat.perfdata.monitor.AbstractPerfDataBufferPrologue.isAccessible.

Get the accessible flag.

pack-priv LongBuffer

Returns:

LongBuffer - a ByteBuffer that accesses the modification time stamp value in the instrumentation buffer header.
modificationTimeStampBuffer()

Return a LongBuffer that accesses the modification timestamp value.

pack-priv IntBuffer

Returns:

LongBuffer - a ByteBuffer that accesses the num_entries value in the instrumentation buffer header.
numEntriesBuffer()

Return an IntBuffer that accesses the number of entries value.

pack-priv IntBuffer

Returns:

IntBuffer - a ByteBuffer that accesses the overflow value in the instrumentation buffer header.
overflowBuffer()

Return an IntBuffer that accesses the overflow value.

pack-priv IntBuffer

Returns:

IntBuffer - a ByteBuffer that accesses the size value in the instrumentation buffer header.
sizeBuffer()

Return an IntBuffer that accesses the size value.

public boolean
supportsAccessible()

Implements abstract sun.jvmstat.perfdata.monitor.AbstractPerfDataBufferPrologue.supportsAccessible.

Test if the accessible flag is supported by this version of the PerfDataBufferPrologue.

pack-priv IntBuffer

Returns:

IntBuffer - a ByteBuffer that accesses the used value in the instrumentation buffer header.
usedBuffer()

Return an IntBuffer that accesses the used value.

Inherited from sun.jvmstat.perfdata.monitor.AbstractPerfDataBufferPrologue:
getByteOrdergetByteOrdergetMagicgetMagicgetMajorVersiongetMajorVersiongetMinorVersiongetMinorVersionmajorVersionBufferminorVersionBuffer

Field Detail

PERFDATA_BUFFER_SIZE_NAMEback to summary
pack-priv static final String PERFDATA_BUFFER_SIZE_NAME
PERFDATA_BUFFER_USED_NAMEback to summary
pack-priv static final String PERFDATA_BUFFER_USED_NAME
PERFDATA_MODTIMESTAMP_NAMEback to summary
pack-priv static final String PERFDATA_MODTIMESTAMP_NAME
PERFDATA_NUMENTRIES_NAMEback to summary
pack-priv static final String PERFDATA_NUMENTRIES_NAME
PERFDATA_OVERFLOW_NAMEback to summary
pack-priv static final String PERFDATA_OVERFLOW_NAME
PERFDATA_PROLOG_ACCESSIBLE_OFFSETback to summary
pack-priv static final int PERFDATA_PROLOG_ACCESSIBLE_OFFSET
PERFDATA_PROLOG_ACCESSIBLE_SIZEback to summary
pack-priv static final int PERFDATA_PROLOG_ACCESSIBLE_SIZE
PERFDATA_PROLOG_ENTRYOFFSET_OFFSETback to summary
pack-priv static final int PERFDATA_PROLOG_ENTRYOFFSET_OFFSET
PERFDATA_PROLOG_ENTRYOFFSET_SIZEback to summary
pack-priv static final int PERFDATA_PROLOG_ENTRYOFFSET_SIZE
PERFDATA_PROLOG_MODTIMESTAMP_OFFSETback to summary
pack-priv static final int PERFDATA_PROLOG_MODTIMESTAMP_OFFSET
PERFDATA_PROLOG_MODTIMESTAMP_SIZEback to summary
pack-priv static final int PERFDATA_PROLOG_MODTIMESTAMP_SIZE
PERFDATA_PROLOG_NUMENTRIES_OFFSETback to summary
pack-priv static final int PERFDATA_PROLOG_NUMENTRIES_OFFSET
PERFDATA_PROLOG_NUMENTRIES_SIZEback to summary
pack-priv static final int PERFDATA_PROLOG_NUMENTRIES_SIZE
PERFDATA_PROLOG_OVERFLOW_OFFSETback to summary
pack-priv static final int PERFDATA_PROLOG_OVERFLOW_OFFSET
PERFDATA_PROLOG_OVERFLOW_SIZEback to summary
pack-priv static final int PERFDATA_PROLOG_OVERFLOW_SIZE
PERFDATA_PROLOG_SIZEback to summary
pack-priv static final int PERFDATA_PROLOG_SIZE

Hides sun.jvmstat.perfdata.monitor.AbstractPerfDataBufferPrologue.PERFDATA_PROLOG_SIZE.

PERFDATA_PROLOG_USED_OFFSETback to summary
pack-priv static final int PERFDATA_PROLOG_USED_OFFSET
PERFDATA_PROLOG_USED_SIZEback to summary
pack-priv static final int PERFDATA_PROLOG_USED_SIZE
SUPPORTED_MAJOR_VERSIONback to summary
private static final int SUPPORTED_MAJOR_VERSION
SUPPORTED_MINOR_VERSIONback to summary
private static final int SUPPORTED_MINOR_VERSION

Constructor Detail

PerfDataBufferPrologueback to summary
public PerfDataBufferPrologue(ByteBuffer byteBuffer) throws MonitorException

Create an instance of PerfDataBufferPrologue from the given ByteBuffer object.

Parameters
byteBuffer:ByteBuffer

the buffer containing the binary header data

Method Detail

getBufferSizeback to summary
public int getBufferSize()

Get the size of the instrumentation memory buffer.

Returns:int

int - the size of the buffer

getEntryOffsetback to summary
public int getEntryOffset()

Get the offset of the first PerfDataEntry.

getModificationTimeStampback to summary
public long getModificationTimeStamp()

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.

getNumEntriesback to summary
public int getNumEntries()

Get the offset of the first PerfDataEntry.

getOverflowback to summary
public int getOverflow()

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.

Returns:int

int - the size of the buffer

getSizeback to summary
public int getSize()

Overrides sun.jvmstat.perfdata.monitor.AbstractPerfDataBufferPrologue.getSize.

Doc from sun.jvmstat.perfdata.monitor.AbstractPerfDataBufferPrologue.getSize.

Get the size of the header portion of the instrumentation buffer.

Returns:int

int - the size of the header

getUsedback to summary
public int getUsed()

Get the utilization of the instrumentation memory buffer.

Returns:int

int - the utilization of the buffer

isAccessibleback to summary
public boolean isAccessible()

Implements abstract sun.jvmstat.perfdata.monitor.AbstractPerfDataBufferPrologue.isAccessible.

Doc from sun.jvmstat.perfdata.monitor.AbstractPerfDataBufferPrologue.isAccessible.

Get the accessible flag. If supported, it indicates that the shared memory region is sufficiently initialized for client access.

Returns:boolean

boolean - the initialized status

modificationTimeStampBufferback to summary
pack-priv LongBuffer modificationTimeStampBuffer()

Return a LongBuffer that accesses the modification timestamp value. This is used to create a Monitor object for this value.

Returns:LongBuffer

LongBuffer - a ByteBuffer that accesses the modification time stamp value in the instrumentation buffer header.

See Also
getModificationTimeStamp()
numEntriesBufferback to summary
pack-priv IntBuffer numEntriesBuffer()

Return an IntBuffer that accesses the number of entries value. This is used to create a Monitor object for this value.

Returns:IntBuffer

LongBuffer - a ByteBuffer that accesses the num_entries value in the instrumentation buffer header.

See Also
getNumEntries()
overflowBufferback to summary
pack-priv IntBuffer overflowBuffer()

Return an IntBuffer that accesses the overflow value. This is used to create a Monitor object for this value.

Returns:IntBuffer

IntBuffer - a ByteBuffer that accesses the overflow value in the instrumentation buffer header.

See Also
getOverflow()
sizeBufferback to summary
pack-priv IntBuffer sizeBuffer()

Return an IntBuffer that accesses the size value. This is used to create a Monitor object for this value.

Returns:IntBuffer

IntBuffer - a ByteBuffer that accesses the size value in the instrumentation buffer header.

See Also
getBufferSize()
supportsAccessibleback to summary
public boolean supportsAccessible()

Implements abstract sun.jvmstat.perfdata.monitor.AbstractPerfDataBufferPrologue.supportsAccessible.

Doc from sun.jvmstat.perfdata.monitor.AbstractPerfDataBufferPrologue.supportsAccessible.

Test if the accessible flag is supported by this version of the PerfDataBufferPrologue. Although not an abstract method, this method should be overridden by version specific subclasses.

Returns:boolean

boolean - the initialized flag support status.

usedBufferback to summary
pack-priv IntBuffer usedBuffer()

Return an IntBuffer that accesses the used value. This is used to create a Monitor object for this value.

Returns:IntBuffer

IntBuffer - a ByteBuffer that accesses the used value in the instrumentation buffer header.

See Also
getUsed()