Package oshi.util.platform.windows

Class PerfDataUtil

java.lang.Object

oshi.util.platform.windows.PerfDataUtil

@ThreadSafe
public final class PerfDataUtil
extends Object

Helper class to centralize the boilerplate portions of PDH counter setup and allow applications to easily add, query, and remove counters.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	PerfDataUtil.PerfCounter	Encapsulates the three string components of a performance counter

Method Summary

Modifier and Type	Method	Description
static boolean	addCounter(com.sun.jna.platform.win32.WinNT.HANDLEByReference query, String path, com.sun.jna.platform.win32.WinNT.HANDLEByReference p)	Adds a pdh counter to a query
static boolean	closeQuery(com.sun.jna.platform.win32.WinNT.HANDLEByReference q)	Close a pdh query
static PerfDataUtil.PerfCounter	createCounter(String object, String instance, String counter)	Create a Performance Counter
static boolean	openQuery(com.sun.jna.platform.win32.WinNT.HANDLEByReference q)	Open a pdh query
static long	queryCounter(com.sun.jna.platform.win32.WinNT.HANDLEByReference counter)	Get value of pdh counter
static long	querySecondCounter(com.sun.jna.platform.win32.WinNT.HANDLEByReference counter)	Get value of pdh counter's second value (base counters)
static boolean	removeCounter(com.sun.jna.platform.win32.WinNT.HANDLEByReference p)	Remove a pdh counter
static long	updateQueryTimestamp(com.sun.jna.platform.win32.WinNT.HANDLEByReference query)	Update a query and get the timestamp

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Details

createCounter

public static PerfDataUtil.PerfCounter createCounter(String object,
 String instance,
 String counter)

Create a Performance Counter

Parameters:

object - The object/path for the counter

instance - The instance of the counter, or null if no instance

counter - The counter name

Returns:

A PerfCounter object encapsulating the object, instance, and counter

updateQueryTimestamp

public static long updateQueryTimestamp(com.sun.jna.platform.win32.WinNT.HANDLEByReference query)

Update a query and get the timestamp

Parameters:

query - The query to update all counters in

Returns:

The update timestamp of the first counter in the query

openQuery

public static boolean openQuery(com.sun.jna.platform.win32.WinNT.HANDLEByReference q)

Open a pdh query

Parameters:

q - pointer to the query

Returns:

true if successful

closeQuery

public static boolean closeQuery(com.sun.jna.platform.win32.WinNT.HANDLEByReference q)

Close a pdh query

Parameters:

q - pointer to the query

Returns:

true if successful

queryCounter

public static long queryCounter(com.sun.jna.platform.win32.WinNT.HANDLEByReference counter)

Get value of pdh counter

Parameters:

counter - The counter to get the value of

Returns:

long value of the counter, or negative value representing an error code

querySecondCounter

public static long querySecondCounter(com.sun.jna.platform.win32.WinNT.HANDLEByReference counter)

Get value of pdh counter's second value (base counters)

Parameters:

counter - The counter to get the value of

Returns:

long value of the counter's second value, or negative value representing an error code

addCounter

public static boolean addCounter(com.sun.jna.platform.win32.WinNT.HANDLEByReference query,
 String path,
 com.sun.jna.platform.win32.WinNT.HANDLEByReference p)

Adds a pdh counter to a query

Parameters:

query - Pointer to the query to add the counter

path - String name of the PerfMon counter. For Vista+, must be in English. Must localize this path for pre-Vista.

p - Pointer to the counter

Returns:

true if successful

removeCounter

public static boolean removeCounter(com.sun.jna.platform.win32.WinNT.HANDLEByReference p)

Remove a pdh counter

Parameters:

p - pointer to the counter

Returns:

true if successful