Nested and Inner Type Summary

Modifier and Type	Class and Description
public static interface	VM.BufferPool Provides access to information on buffer usage.
private static class	VM.BufferPoolsHolder

Field Summary

Modifier and Type	Field and Description
private static long	directMemory
private static volatile int	finalRefCount
private static volatile int	initLevel
private static final int	JAVA_LANG_SYSTEM_INITED
private static boolean	javaLangInvokeInited
private static final int	JVMTI_THREAD_STATE_ALIVE
private static final int	JVMTI_THREAD_STATE_BLOCKED_ON_MONITOR_ENTER
private static final int	JVMTI_THREAD_STATE_RUNNABLE
private static final int	JVMTI_THREAD_STATE_TERMINATED
private static final int	JVMTI_THREAD_STATE_WAITING_INDEFINITELY
private static final int	JVMTI_THREAD_STATE_WAITING_WITH_TIMEOUT
private static final Object	lock
private static final int	MODULE_SYSTEM_INITED
private static Boolean	pageAlignDirectMemory
private static volatile int	peakFinalRefCount
private static Map<String, String>	savedProps
private static final int	SYSTEM_BOOTED
private static final int	SYSTEM_LOADER_INITIALIZING
private static final int	SYSTEM_SHUTDOWN

Constructor Summary

Access	Constructor and Description
public	VM()

Method Summary

Modifier and Type	Method and Description
public static void	addFinalRefCount(int n)
public static void	awaitInitLevel(int value) Waits for the init level to get the given value.
public static List<VM.BufferPool>	getBufferPools() Returns: the list of buffer pools.
public static native long	getegid() Returns the effective group ID of the calling process, or -1 if the value is not available.
public static native long	geteuid() Returns the effective user ID of the calling process, or -1 if the value is not available.
public static int	getFinalRefCount()
public static native long	getgid() Returns the real group ID of the calling process, or -1 if the value is not available.
public static native long	Returns: A nanosecond time stamp adjustment in the form of a single long. If the offset is too far off the current time, this method returns -1. In that case, the caller should call this method again, passing a more accurate offset. getNanoTimeAdjustment(long The offset in seconds from which the nanosecond time stamp should be computed. offsetInSeconds) Get a nanosecond time stamp adjustment in the form of a single long.
public static int	getPeakFinalRefCount()
public static native String[]	getRuntimeArguments() Returns the VM arguments for this runtime environment.
public static Map<String, String>	getSavedProperties() Gets an unmodifiable view of the system properties saved at system initialization time.
public static String	getSavedProperty(String key) Returns the system property of the specified key saved at system initialization time.
public static native long	getuid() Returns the real user ID of the calling process, or -1 if the value is not available.
public static PrintStream	initialErr() Return the initial value of System.err that was set during VM initialization.
private static native void	initialize()
public static void	initializeOSEnvironment()
public static void	initLevel(int value) Sets the init level.
public static int	initLevel() Returns the current init level.
public static boolean	isBooted() Returns `true` if the VM is fully initialized.
public static boolean	isDirectMemoryPageAligned()
public static boolean	isJavaLangInvokeInited()
public static boolean	isModuleSystemInited() Returns `true` if the module system has been initialized.
public static boolean	isSetUID() Returns `true` if we are in a set UID program.
public static boolean	isShutdown() Returns `true` if the VM has been shutdown
public static boolean	isSupportedClassFileVersion(int major, int minor) Tests if the given version is a supported `class` file version.
public static boolean	isSupportedModuleDescriptorVersion(int major, int minor) Tests if the given version is a supported `class` file version for module descriptor.
public static boolean	isSystemDomainLoader(ClassLoader loader) Returns true if the given class loader is the bootstrap class loader or the platform class loader.
public static ClassLoader	latestUserDefinedLoader()
private static native ClassLoader	latestUserDefinedLoader0()
public static long	maxDirectMemory()
public static void	saveProperties(Map<String, String> props)
public static void	setJavaLangInvokeInited()
public static void	shutdown() Set shutdown state.
public static Thread.State	toThreadState(int threadStatus) Returns Thread.State for the given threadStatus

Inherited from java.lang.Object:: clone equals finalize getClass hashCode notify notifyAll toString wait wait wait

Field Detail

directMemory	back to summary
private static long directMemory

finalRefCount	back to summary
private static volatile int finalRefCount

initLevel	back to summary
private static volatile int initLevel

JAVA_LANG_SYSTEM_INITED	back to summary
private static final int JAVA_LANG_SYSTEM_INITED

javaLangInvokeInited	back to summary
private static boolean javaLangInvokeInited Annotations @Stable

JVMTI_THREAD_STATE_ALIVE	back to summary
private static final int JVMTI_THREAD_STATE_ALIVE

JVMTI_THREAD_STATE_BLOCKED_ON_MONITOR_ENTER	back to summary
private static final int JVMTI_THREAD_STATE_BLOCKED_ON_MONITOR_ENTER

JVMTI_THREAD_STATE_RUNNABLE	back to summary
private static final int JVMTI_THREAD_STATE_RUNNABLE

JVMTI_THREAD_STATE_TERMINATED	back to summary
private static final int JVMTI_THREAD_STATE_TERMINATED

JVMTI_THREAD_STATE_WAITING_INDEFINITELY	back to summary
private static final int JVMTI_THREAD_STATE_WAITING_INDEFINITELY

JVMTI_THREAD_STATE_WAITING_WITH_TIMEOUT	back to summary
private static final int JVMTI_THREAD_STATE_WAITING_WITH_TIMEOUT

lock	back to summary
private static final Object lock

MODULE_SYSTEM_INITED	back to summary
private static final int MODULE_SYSTEM_INITED

pageAlignDirectMemory	back to summary
private static Boolean pageAlignDirectMemory Annotations @Stable

peakFinalRefCount	back to summary
private static volatile int peakFinalRefCount

savedProps	back to summary
private static Map<String, String> savedProps

SYSTEM_BOOTED	back to summary
private static final int SYSTEM_BOOTED

SYSTEM_LOADER_INITIALIZING	back to summary
private static final int SYSTEM_LOADER_INITIALIZING

SYSTEM_SHUTDOWN	back to summary
private static final int SYSTEM_SHUTDOWN

Constructor Detail

VM	back to summary
public VM()

Method Detail

addFinalRefCount	back to summary
public static void addFinalRefCount(int n)

awaitInitLevel	back to summary
public static void awaitInitLevel(int value) throws InterruptedException Waits for the init level to get the given value.

getBufferPools	back to summary
public static List<VM.BufferPool> getBufferPools() Returns:List<VM.BufferPool> the list of buffer pools.

getegid	back to summary
public static native long getegid() Returns the effective group ID of the calling process, or -1 if the value is not available.

geteuid	back to summary
public static native long geteuid() Returns the effective user ID of the calling process, or -1 if the value is not available.

getFinalRefCount	back to summary
public static int getFinalRefCount()

getgid	back to summary
public static native long getgid() Returns the real group ID of the calling process, or -1 if the value is not available.

getNanoTimeAdjustment back to summary

getNanoTimeAdjustment	back to summary
public static native long getNanoTimeAdjustment(long offsetInSeconds) Get a nanosecond time stamp adjustment in the form of a single long. This value can be used to create an instant using `java.time.Instant.ofEpochSecond(offsetInSeconds, getNanoTimeAdjustment(offsetInSeconds))`. The value returned has the best resolution available to the JVM on the current system. This is usually down to microseconds - or tenth of microseconds - depending on the OS/Hardware and the JVM implementation. API Note The offset should be recent enough - so that `offsetInSeconds` is within `+/- 2^32` seconds of the current UTC time. If the offset is too far off, `-1` will be returned. As such, `-1` must not be considered as a valid nano time adjustment, but as an exception value indicating that an offset closer to the current time should be used. Parameters offsetInSeconds:long The offset in seconds from which the nanosecond time stamp should be computed. Returns:long A nanosecond time stamp adjustment in the form of a single long. If the offset is too far off the current time, this method returns -1. In that case, the caller should call this method again, passing a more accurate offset.

public static native long getNanoTimeAdjustment(long offsetInSeconds)

Get a nanosecond time stamp adjustment in the form of a single long. This value can be used to create an instant using java.time.Instant.ofEpochSecond(offsetInSeconds, getNanoTimeAdjustment(offsetInSeconds)).

The value returned has the best resolution available to the JVM on the current system. This is usually down to microseconds - or tenth of microseconds - depending on the OS/Hardware and the JVM implementation.

API Note

The offset should be recent enough - so that offsetInSeconds is within +/- 2^32 seconds of the current UTC time. If the offset is too far off, -1 will be returned. As such, -1 must not be considered as a valid nano time adjustment, but as an exception value indicating that an offset closer to the current time should be used.

Parameters

offsetInSeconds:long: The offset in seconds from which the nanosecond time stamp should be computed.

Returns:long

A nanosecond time stamp adjustment in the form of a single long. If the offset is too far off the current time, this method returns -1. In that case, the caller should call this method again, passing a more accurate offset.

getPeakFinalRefCount	back to summary
public static int getPeakFinalRefCount()

getRuntimeArguments	back to summary
public static native String[] getRuntimeArguments() Returns the VM arguments for this runtime environment. Implementation Note The HotSpot JVM processes the input arguments from multiple sources in the following order: 1. JAVA_TOOL_OPTIONS environment variable 2. Options from JNI Invocation API 3. _JAVA_OPTIONS environment variable If VM options file is specified via -XX:VMOptionsFile, the vm options file is read and expanded in place of -XX:VMOptionFile option.

getRuntimeArguments

back to summary

public static native String[] getRuntimeArguments()

Returns the VM arguments for this runtime environment.

Implementation Note

The HotSpot JVM processes the input arguments from multiple sources in the following order: 1. JAVA_TOOL_OPTIONS environment variable 2. Options from JNI Invocation API 3. _JAVA_OPTIONS environment variable If VM options file is specified via -XX:VMOptionsFile, the vm options file is read and expanded in place of -XX:VMOptionFile option.

getSavedProperties	back to summary
public static Map<String, String> getSavedProperties() Gets an unmodifiable view of the system properties saved at system initialization time. This method should only be used for the system properties that are not changed during runtime. Note that the saved system properties do not include the ones set by java.lang.VersionProps.init().

getSavedProperty	back to summary
public static String getSavedProperty(String key) Returns the system property of the specified key saved at system initialization time. This method should only be used for the system properties that are not changed during runtime. Note that the saved system properties do not include the ones set by java.lang.VersionProps.init().

getuid	back to summary
public static native long getuid() Returns the real user ID of the calling process, or -1 if the value is not available.

initialErr	back to summary
public static PrintStream initialErr() Return the initial value of System.err that was set during VM initialization.

initialize	back to summary
private static native void initialize()

initializeOSEnvironment	back to summary
public static void initializeOSEnvironment()

initLevel back to summary

initLevel	back to summary
public static void initLevel(int value) Sets the init level. See Also `java.lang.System#initPhase1`, `java.lang.System#initPhase2`, `java.lang.System#initPhase3`

public static void initLevel(int value)

Sets the init level.

See Also: java.lang.System#initPhase1, java.lang.System#initPhase2, java.lang.System#initPhase3

initLevel	back to summary
public static int initLevel() Returns the current init level.

isBooted	back to summary
public static boolean isBooted() Returns `true` if the VM is fully initialized.

isDirectMemoryPageAligned	back to summary
public static boolean isDirectMemoryPageAligned()

isJavaLangInvokeInited	back to summary
public static boolean isJavaLangInvokeInited()

isModuleSystemInited back to summary

isModuleSystemInited	back to summary
public static boolean isModuleSystemInited() Returns `true` if the module system has been initialized. See Also `java.lang.System#initPhase2`

public static boolean isModuleSystemInited()

Returns true if the module system has been initialized.

See Also: java.lang.System#initPhase2

isSetUID	back to summary
public static boolean isSetUID() Returns `true` if we are in a set UID program.

isShutdown	back to summary
public static boolean isShutdown() Returns `true` if the VM has been shutdown

isSupportedClassFileVersion back to summary

isSupportedClassFileVersion	back to summary
public static boolean isSupportedClassFileVersion(int major, int minor) Tests if the given version is a supported `class` file version. A `class` file depends on the preview features of Java SE `N` if the major version is `N` and the minor version is 65535. This method returns `true` if the given version is a supported `class` file version regardless of whether the preview features are enabled or not. Java Virtual Machine Specification 4.1 Table 4.1-A. class file format major versions

public static boolean isSupportedClassFileVersion(int major, int minor)

Tests if the given version is a supported class file version. A class file depends on the preview features of Java SE N if the major version is N and the minor version is 65535. This method returns true if the given version is a supported class file version regardless of whether the preview features are enabled or not.

Java Virtual Machine Specification: 4.1 Table 4.1-A. class file format major versions

isSupportedModuleDescriptorVersion	back to summary
public static boolean isSupportedModuleDescriptorVersion(int major, int minor) Tests if the given version is a supported `class` file version for module descriptor. major.minor version >= 53.0

isSystemDomainLoader	back to summary
public static boolean isSystemDomainLoader(ClassLoader loader) Returns true if the given class loader is the bootstrap class loader or the platform class loader.

latestUserDefinedLoader	back to summary
public static ClassLoader latestUserDefinedLoader()

latestUserDefinedLoader0	back to summary
private static native ClassLoader latestUserDefinedLoader0()

maxDirectMemory	back to summary
public static long maxDirectMemory()

saveProperties	back to summary
public static void saveProperties(Map<String, String> props)

setJavaLangInvokeInited	back to summary
public static void setJavaLangInvokeInited()

shutdown back to summary

public static void shutdown()

Set shutdown state. Shutdown completes when all registered shutdown hooks have been run.

See Also: java.lang.Shutdown

toThreadState	back to summary
public static Thread.State toThreadState(int threadStatus) Returns Thread.State for the given threadStatus

jdk.internal.misc back to summary

public Interface VM.BufferPool

Provides access to information on buffer usage.

Method Summary

Modifier and Type	Method and Description
public long	getCount()
public long	getMemoryUsed()
public String	getName()
public long	getTotalCapacity()

Method Detail

getCount	back to summary
public long getCount()

getMemoryUsed	back to summary
public long getMemoryUsed()

getName	back to summary
public String getName()

getTotalCapacity	back to summary
public long getTotalCapacity()

jdk.internal.misc back to summary

private Class VM.BufferPoolsHolder

Class Inheritance

extends Object

java.lang.Object
jdk.internal.misc.VM.BufferPoolsHolder

Field Summary

Modifier and Type	Field and Description
pack-priv static final List<VM.BufferPool>	BUFFER_POOLS

Constructor Summary

Access	Constructor and Description
private	BufferPoolsHolder()

Method Summary

Inherited from java.lang.Object:: clone equals finalize getClass hashCode notify notifyAll toString wait wait wait

Field Detail

BUFFER_POOLS	back to summary
pack-priv static final List<VM.BufferPool> BUFFER_POOLS

Constructor Detail

BufferPoolsHolder	back to summary
private BufferPoolsHolder()

public Class VM

Nested and Inner Type Summary

Field Summary

Constructor Summary

Method Summary

Field Detail

Constructor Detail

Method Detail

public Interface VM.BufferPool

Method Summary

Method Detail

private Class VM.BufferPoolsHolder

Field Summary

Constructor Summary

Method Summary

Field Detail

Constructor Detail