org.agrona

Class SystemUtil

java.lang.Object

org.agrona.SystemUtil

public class SystemUtil
extends java.lang.Object

Utilities for inspecting the system.

Field Summary

Fields

Modifier and Type	Field and Description
static long	PID_NOT_FOUND PID value if a process id could not be determined.

Constructor Summary

Constructors

Constructor and Description
SystemUtil()

Method Summary

Modifier and Type	Method and Description
static long	getDurationInNanos(java.lang.String propertyName, long defaultValue) Get a string representation of a time duration with an optional suffix of 's', 'ms', 'us', or 'ns' suffix to indicate seconds, milliseconds, microseconds, or nanoseconds respectively.
static long	getPid() Return the current process id from the OS.
static int	getSizeAsInt(java.lang.String propertyName, int defaultValue) Get a size value as an int from a system property.
static long	getSizeAsLong(java.lang.String propertyName, long defaultValue) Get a size value as a long from a system property.
static boolean	isDebuggerAttached() Is a debugger attached to the JVM?
static void	loadPropertiesFile(java.lang.String filenameOrUrl) Load system properties from a given filename or url.
static void	loadPropertiesFiles(java.lang.String[] filenamesOrUrls) Load system properties from a given set of filenames or URLs.
static java.lang.String	osName() Get the name of the operating system as a lower case String.
static long	parseDuration(java.lang.String propertyName, java.lang.String propertyValue) Parse a string representation of a time duration with an optional suffix of 's', 'ms', 'us', or 'ns' to indicate seconds, milliseconds, microseconds, or nanoseconds respectively.
static long	parseSize(java.lang.String propertyName, java.lang.String propertyValue) Parse a string representation of a value with optional suffix of 'g', 'm', and 'k' suffix to indicate gigabytes, megabytes, or kilobytes respectively.
static java.lang.String	threadDump() Get a formatted dump of all threads with associated state and stack traces.

Methods inherited from class java.lang.Object

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

Field Detail

PID_NOT_FOUND

public static final long PID_NOT_FOUND

PID value if a process id could not be determined. This value should be equal to a kernel only process id for the platform so that it does not indicate a real process id.

See Also:

Constant Field Values

Constructor Detail

SystemUtil

public SystemUtil()

Method Detail

osName

public static java.lang.String osName()

Get the name of the operating system as a lower case String.

This is what is returned from System.getProperty("os.name").toLowerCase().

Returns:

the name of the operating system as a lower case String.

getPid

public static long getPid()

Return the current process id from the OS.

Returns:

current process id or PID_NOT_FOUND if PID was not able to be found.

See Also:

PID_NOT_FOUND

isDebuggerAttached

public static boolean isDebuggerAttached()

Is a debugger attached to the JVM?

Returns:

true if attached otherwise false.

threadDump

public static java.lang.String threadDump()

Get a formatted dump of all threads with associated state and stack traces.

Returns:

a formatted dump of all threads with associated state and stack traces.

loadPropertiesFile

public static void loadPropertiesFile(java.lang.String filenameOrUrl)

Load system properties from a given filename or url.

File is first searched for in resources using the system ClassLoader, then file system, then URL. All are loaded if multiples found.

Parameters:

filenameOrUrl - that holds properties

loadPropertiesFiles

public static void loadPropertiesFiles(java.lang.String[] filenamesOrUrls)

Load system properties from a given set of filenames or URLs.

Parameters:

filenamesOrUrls - that holds properties

See Also:

loadPropertiesFile(String)

getSizeAsInt

public static int getSizeAsInt(java.lang.String propertyName,
                               int defaultValue)

Get a size value as an int from a system property. Supports a 'g', 'm', and 'k' suffix to indicate gigabytes, megabytes, or kilobytes respectively.

Parameters:

propertyName - to lookup.

defaultValue - to be applied if the system property is not set.

Returns:

the int value.

Throws:

java.lang.NumberFormatException - if the value is out of range or mal-formatted.

getSizeAsLong

public static long getSizeAsLong(java.lang.String propertyName,
                                 long defaultValue)

Get a size value as a long from a system property. Supports a 'g', 'm', and 'k' suffix to indicate gigabytes, megabytes, or kilobytes respectively.

Parameters:

propertyName - to lookup.

defaultValue - to be applied if the system property is not set.

Returns:

the long value.

Throws:

java.lang.NumberFormatException - if the value is out of range or mal-formatted.

parseSize

public static long parseSize(java.lang.String propertyName,
                             java.lang.String propertyValue)

Parse a string representation of a value with optional suffix of 'g', 'm', and 'k' suffix to indicate gigabytes, megabytes, or kilobytes respectively.

Parameters:

propertyName - that associated with the size value.

propertyValue - to be parsed.

Returns:

the long value.

Throws:

java.lang.NumberFormatException - if the value is out of range or mal-formatted.

getDurationInNanos

public static long getDurationInNanos(java.lang.String propertyName,
                                      long defaultValue)

Get a string representation of a time duration with an optional suffix of 's', 'ms', 'us', or 'ns' suffix to indicate seconds, milliseconds, microseconds, or nanoseconds respectively.

If the resulting duration is greater than Long.MAX_VALUE then Long.MAX_VALUE is used.

Parameters:

propertyName - associated with the duration value.

defaultValue - to be used if the property is not present.

Returns:

the long value.

Throws:

java.lang.NumberFormatException - if the value is negative or malformed.

parseDuration

public static long parseDuration(java.lang.String propertyName,
                                 java.lang.String propertyValue)

Parse a string representation of a time duration with an optional suffix of 's', 'ms', 'us', or 'ns' to indicate seconds, milliseconds, microseconds, or nanoseconds respectively.

If the resulting duration is greater than Long.MAX_VALUE then Long.MAX_VALUE is used.

Parameters:

propertyName - associated with the duration value.

propertyValue - to be parsed.

Returns:

the long value.

Throws:

java.lang.NumberFormatException - if the value is negative or malformed.